Monthly Archives: April 2020

Maths, reading and better nutrition: all the reasons to cook with your kids

Maths, reading and better nutrition: all the reasons to cook with your kids

April 22, 2020 6.06am AEST


  1. Clare Collins Professor in Nutrition and Dietetics, University of Newcastle
  2. Berit Follong PhD candidate, nutrition and mathematics education, University of Newcastle
  3. Tamara Bucher Senior Researcher, University of Newcastle

Disclosure statement

Clare Collins is affiliated with the Priority Research Centre for Physical Activity and Nutrition, the University of Newcastle, NSW. She is an NHMRC Senior Research and Gladys M Brawn Research Fellow. She has received research grants from NHMRC, ARC, Hunter Medical Research Institute, Meat and Livestock Australia, Diabetes Australia, Heart Foundation, Bill and Melinda Gates Foundation, nib foundation, Rijk Zwaan Australia and Greater Charitable Foundation. She has consulted to SHINE Australia, Novo Nordisk, Quality Bakers, the Sax Institute and the ABC. She was a team member conducting systematic reviews to inform the Australian Dietary Guidelines update and the Heart Foundation evidence reviews on meat and dietary patterns.

Berit Follong is affiliated with the Priority Research Centre (PRC) for Physical Activity and Nutrition and PRC for Health Behaviour, the University of Newcastle, NSW. She is a PhD candidate investigating the integration of nutrition and mathematics in Australian primary schools.

Tamara Bucher is affiliated with the Priority Research Centre (PRC) for Physical Activity and Nutrition and PRC for Health Behaviour, the University of Newcastle, NSW. She has received research grants from the Swiss National Science Foundation, the Swiss Foundation for Nutrition Research, The European Union, Universities Australia and food industry including Rijk Zwaan, Nestec Ltd and Goodman fielder. She is a member of the International Society for Behavioural Nutrition and Physical Activity (ISBNPA), the Nutrition Society Australia (NSA) and the Australian Institute of Food Science and Technology (AIFST).


University of Newcastle

University of Newcastle provides funding as a member of The Conversation AU.

If you’re schooling your children at home, chances are you’re very time poor. By teaching your children to cook, you could bundle up some learning while also getting dinner or lunch prepared.

Teaching children to cook healthy food helps them gain knowledge and skills across a range of subjects simultaneously. The bonus is, you could get a healthy meal prepared as well.

By focusing on nutritious recipes you’ll also address personal development, health and physical education topics.

Read more: What is homeschooling? And should I be doing that with my kid during the coronavirus lockdown?

Why cooking?

Being able to apply maths and science concepts to everyday situations helps develop self-confidence in daily activities.

Learning to follow a recipe and prepare food spans a number of core subjects such as English, through reading and comprehension. Being able to weigh and measure out ingredients draws on maths concepts of volume and measurement, and the skills of inquiry and problem solving are central to science.

Teaching children to cook, and focusing on preparing healthy foods, integrates knowledge from all these subjects and maximises learning opportunities by helping your children develop motivation and communication skills.

A study in 18 year four classes integrated maths and science into classroom teaching, using hands-on food based nutrition activities. The children in these classes improved their nutrition knowledge, while their knowledge in science and mathematics also improved significantly, compared to children in the 16 control classes who didn’t receive the integrated lessons.

A review of classroom healthy eating interventions found active learning activities such as cooking, food preparation and school gardening had the biggest impact on improving nutrition knowledge and dietary patterns.

This was especially the case when it came to getting children to eat more fruit and vegetables and reducing their intake of sugar and total daily kilojoules.

Read more: Want to be happier, healthier, save money? It’s time to get cooking

Children who cook with their parents are likely to eat more nutritious foods. Shutterstock

In Australia neither children nor their parents eat enough vegetables. Energy-dense, nutrient-poor foods (junk) account for one third of total daily energy intakes, and 41% for children and teenagers.

The Australian Guide to Healthy Eating recommends we keep junk food intakes low, while aiming for five serves of vegetables and two serves of fruit daily to stay healthy and prevent chronic diseases like type two diabetes and heart disease.

Only one in 20 adults and one in 17 children under 18 years of age meet these daily recommendations for both vegetables and fruit.

Read more: How much food should my child be eating? And how can I get them to eat more healthily?

Involving children and teenagers in food preparation helps promote healthy eating habits, including eating more vegetables and fruit. An experimental study with 47 children aged 6-10 found when children cooked with their parents, they ate 26% more chicken and 76% more salad and felt happier compared to when the parent cooked alone.

Even watching healthy cooking TV shows can make a difference. A recent study with more than 100 children aged 10-12 found that after watching healthy food being prepared in a TV video, children were twice as likely to choose to eat healthily.

You can make cooking more challenging

It is common for children to think they don’t like maths and metrics, with achievement and engagement in maths declining globally. So it is important to find new ways to interest children in these areas.

Cooking is a real-life way to make abstract concepts relevant to your child. Show them how to compare, measure and order foods from smallest to biggest using metric units such as mass (weight), length, area and volume.

Basic maths skills are essential to accurately estimate food portion sizes, follow recipes and understand food labels.

This clear link between cooking, nutrition and maths highlights the potential to enhance learning in both subject areas.

To challenge your children’s maths ability even further, try limiting the cooking utensils used so more calculation is needed. For example, when a recipe calls for one cup (250mL) of rice, use the ¼ cup (62.5mL) measure and ask your children to work out how many of these they need to add.

Cooking helps children put abstract maths concepts into practice. Shutterstock

Or use different types of kitchen utensils such as a measuring jug rather than a measuring cup to work out the gradations and pour the content of the cup into the jug and vice versa.

Cooking also provides the opportunity to discuss important nutrition topics with your child. Children find it easier to work out which foods are healthy and harder to identify which are unhealthy and why.

Try sorting a recipe’s ingredients into their basic food groups before you start cooking. Or try to estimate the number of serves per food group you have added when following a recipe.

Food art – if it looks good it tastes good

Arranging healthy foods in fun and creative ways helps kids like these foods more. An international study with 433 children from 14 countries showed beautiful food designs created using spinach and fruit increased children’s desire to eat these foods.

Using food art to improve enjoyment of healthy eating is a promising way to help picky eaters eat healthy foods.

Lots of resources are available to help make healthy cooking fun, fast and inexpensive.

Our healthy fast food cooking challenge is a collection of videos that show how well-liked classics such as burgers and pizza can be prepared in healthy ways, just as fast and at lower cost.

For some extra activities on food and measurement for primary school children, and a chance to explore imperial measurement, explore the USA FOODMASTER project.

How to beat weight gain at menopause

The most common complaint I get from my menopausal patients is weight gain. Insomnia is number two. This article might help many of you.

How to beat weight gain at menopause

April 24, 2020 6.00am AEST


  1. Clare Collins Professor in Nutrition and Dietetics, University of Newcastle
  2. Jenna Hollis Conjoint Lecturer, University of Newcastle
  3. Lauren Williams Professor of Nutrition and Dietetics, Griffith University

Disclosure statement

Clare Collins is affiliated with the Priority Research Centre for Physical Activity and Nutrition, the University of Newcastle, NSW. She is an NHMRC Senior Research and Gladys M Brawn Research Fellow. She has received research grants from NHMRC, ARC, Hunter Medical Research Institute, Meat and Livestock Australia, Diabetes Australia, Heart Foundation, Bill and Melinda Gates Foundation, nib foundation, Rijk Zwaan Australia and Greater Charitable Foundation. She has consulted to SHINE Australia, Novo Nordisk, Quality Bakers, the Sax Institute and the ABC. She was a team member conducting systematic reviews to inform the Australian Dietary Guidelines update and the Heart Foundation evidence reviews on meat and dietary patterns.

Jenna Hollis is affiliated with School of Medicine and Public Health, University of Newcastle and Hunter New England Population Health (Australia). She is a Hunter Medical Research Institute (HMRI) Research Fellow in Public Health supported by the Prevention Research Support Program and funded by the New South Wales Ministry of Health. She has received research grants from the NHMRC, Department of Education and Training (Australian Government), HMRI, University of Newcastle and the Australian and New Zealand Obesity Society (ANZOS). Jenna is a Visiting Research Fellow at the Medical Research Council Lifecourse Epidemiology Unit, University of Southampton (UK). She participated in the Australian Academy of Science and Theo Murphy’s High Flyers Think Tank on Food and Nutrition Science in 2017, and the European Nutrition Leadership Platform in 2015.

Lauren Williams is affiliated with the School of Allied Health Sciences at Griffith University and the Menzies Health Research Institute of Queensland. She has honorary appointments with the Faculty of Health and Medicine at the University of Newcastle and the Faculty of Health at the University of Canberra. She currently receives funding from the Woolworths Nutrition-Related Health Services Research.


Griffith University
University of Newcastle

Griffith University and University of Newcastle provide funding as members of The Conversation AU.

For many women, the journey through menopause is a roller coaster of symptoms including hot flushes, night sweats, sleep disturbance, dry and itchy skin, mood changes, anxiety, depression and weight gain. For some, it can be relatively uneventful.

Menopause is medically defined as not having any menstrual bleeding for 12 months. Most women reach this milestone between the ages of 45 to 55.

Even though weight gain is common, you can beat it by using menopause as an opportunity to reset your eating and exercise habits.

Read more: Thinking of menopausal hormone therapy? Here’s what you can expect from your GP

Do women gain weight at menopause?

Australian women tend to gain weight as they age.

During menopause, women also experience a shift in how fat stores are distributed around the body. Fat tends to move from the thigh region up to the waist and abdomen.

A review of studies that quantified changes in body fat stores before and after menopause found total body fat mass also increased significantly.

While the average weight increase was only about one kilogram, the increase in percentage total body fat was almost 3%, with fat on the trunk increasing by 5.5% and total leg fat decreasing around 3%.

Average waist circumference increased by about 4.6 centimetres and hips by 2.0 centimetres.

Other bad news is that once postmenopausal, women have lower total daily energy needs. This is partly because body fat requires less energy to maintain it compared to muscle. So even if your weight doesn’t change, the increase in body fat means your body needs fewer kilojoules each day.

Energy requirements decrease after menopause. Shutterstock

In addition to this, the menstrual cycle had a small energy cost to maintain ovarian function. This amounted to about 200 kilojoules a day, which is now “saved”.

The bottom line is that unless your transition to menopause is accompanied by a reduction in your total energy intake or an increase in your physical activity, you’re at high risk of weight gain.

But there is some good news

Around 60% of women manage to avoid weight gain at menopause.

They manage this by either decreasing the total amount of food they eat, cutting down on fat and sugar, using commercial weight loss programs, doing more exercise, or a combination of all these.

They key thing is that they change some aspects of their lifestyle.

So what works best?

Until recently, only three major studies had tested interventions.

The Women’s Healthy Lifestyle Project compared the impact of receiving support to improve diet and exercise habits over four years covering menopause, to making no changes at all.

Women who changed their lifestyle had lower body weights, less abdominal fat and better blood sugar levels compared to those in the control group.

The second study, of 168 women, enrolled them into a 90 minute Nordic walking program, three times a week.

This was associated with a reduction in weight, body fat and waist circumference, as well as blood levels of bad cholesterol and fats, highlighting the benefits of endurance walking.

The third study divided 175 Nigerian women into two groups: one group undertook a 12-week circuit training exercise program, the other was a control group.

Women in the exercise group reduced their waist circumference relative to their hips, indicating a reduction in abdominal fat, even though their total body weight did not change.

Read more: Health Check: what’s the best diet for weight loss?

The 40-something trial

More recently, we studied 54 women aged 45-50 years in the “40-Something” trial.

We randomly assigned half the participants to receive healthy eating and physical activity support from health professionals, using motivational interviewing to encourage behaviour change. The other half received information only and were asked to self-direct their lifestyle changes.

Our aim was to prevent weight gain in women who were in either the overweight or healthy weight range as they entered early menopause.

We encouraged women who were overweight to reduce their body weight to achieve a body mass index (BMI) in the healthy weight range (BMI 18 to 25). We encouraged women already in the healthy weight range to maintain their weight within one kilogram.

We gave all women the same healthy lifestyle advice, including to eat:

  • 2 serves of fruit and at least 5 serves of vegetables every day
  • 1-1.5 serves of meat or meat alternatives
  • 2-3 serves of dairy
  • wholegrain breads and cereals.

And to:

  • limit foods high in fat and sugar
  • cut down on meals eaten outside the home
  • engage in moderate to vigorous physical activity for 150-250 minutes per week
  • sit for less than three hours per day
  • take at least 10,000 steps per day.
Eating a variety of vegetables is an important component of healthy eating. Shutterstock

Women in the intervention group had five consultations with a dietitian and exercise physiologist over one year to provide support and motivation to change their eating habits and physical activity.

After two years, women in the intervention group had lower body weights, less body fat and smaller waist circumferences compared to the control group who received information pamphlets only.

When we evaluated changes based on their starting BMI, the intervention was more effective for preventing weight gain in women initially of a healthy weight.

Of all the health advice, eating five serves of vegetables and taking 10,000 steps per day were the most effective strategies for long-term weight control during menopause.

Read more: What is a balanced diet anyway?

Although weight gain, and especially body fat gain, is usual during the menopausal transition, you can beat it.

Rather than menopause being a time to put your feet up, it’s a time to step up your physical activity and boost your efforts to eat a healthy, balanced diet, especially when it comes to the frequency and variety of vegetables you eat.

What is lupus and how is stress implicated?

Explainer: what is lupus and how is stress implicated?

Thanks to Selena Gomez and Dr House, most of us have heard of lupus. But most of us don’t know what it is, and until recently, none of us were sure whether stress could be a risk factor.

The simplest way to understand lupus is “your immune system gone wrong”.

We have evolved powerful immune systems to detect, attack, and destroy invading microbes. But if the immune system makes an error in the “detect” stage – incorrectly recognising some part of us as foreign – it will attack it with all of the tools at its disposal.

This self-directed, or “auto”-immunity, is the basis of countless diseases, from juvenile diabetes to multiple sclerosis. But unlike those examples, in which the immune system attacks just one tissue, in lupus all tissues of the body can be targeted.

Read more: Explainer: what are autoimmune diseases?

This can mean anything from a rash and arthritis to the immune system disrupting the function of the brain, heart, and kidney. Some sufferers may have minor symptoms such as tiredness and joint pain that resolves within a few months, but for some the disease can last for years and require transplantation of damaged organs.

These symptoms can arrive in any order at any time, and cause a severe loss of quality of life and reduction in life expectancy. As lupus mostly affects young adult women, the impact of this is great.

Why does this happen?

We are much closer now to being able to answer this question, thanks in part to being able to analyse gene expression in people with the disease.

We know from genetic studies that at least some risk of lupus is inherited from our parents, but we also know that inheritance explains only a fraction of the risk of getting lupus. So other factors must contribute.

It now appears that a large subset of lupus patients’ disease is caused by mechanisms the immune system normally uses to combat viruses. The immune system produces virus-fighting hormones (called “cytokines”) such as interferon – which activates the production of antibodies and destructive inflammation intended to kill the infection. When this happens by error, and is directed at the self, tissue inflammation and damage occur.

Current treatments are limited to non-specific immune suppressant drugs “borrowed” from other diseases such as arthritis, and drugs used to stop an organ recipient’s body rejecting the donor organ. Although life-saving in many cases, these drugs have major side effects and don’t control all patients’ disease.

Read more: Man flu is real, but women get more autoimmune diseases and allergies

How is stress related to lupus?

As a rheumatologist I treat patients in hospital with musculoskeletal diseases and autoimmune conditions. A patient of mine suffering from lupus had, some time prior to diagnosis, been the victim of an assault, which caused post-traumatic stress disorder (PTSD).

This case posed to me, and more importantly to the patient, the question of whether stress could have led to the development of lupus. Until recently this question has been effectively unanswerable.

A new study looked at data reporting on the association of trauma and PTSD with the incidence of lupus. It found that PTSD was associated with a nearly threefold increase in risk of subsequently developing lupus.

A study found a link between PTSD and auto-immune conditions in service personnel. from

A past history of trauma, regardless of carrying a PTSD diagnosis, was associated with a similar threefold increase in the risk of lupus.

These findings confirm a previous study of ex-service personnel, in which PTSD was both disturbingly prevalent and also a powerful risk factor for the development of autoimmune diseases, including lupus.

Read more: Why ‘It’s never lupus’ – television, illness and the making of a meme

The association of stress and the immune system dates back to the 1930s, when pioneering endocrinologist Hans Selye found that there are distinct changes in the body in response to a threat. The term “stress” was also attributed to Selye, albeit coined much later.

Crucially, Selye also observed that stress results in disturbances in steroid hormone production. As we now know, the body’s naturally occurring steroids act through the same pathway as steroid drugs used to treat lupus. This provides a possible mechanism for the connection between stress and the control of immunity.

Intriguingly, some organ manifestations of lupus, such as severe skin or blood disease, are notoriously resistant to steroids, and recent laboratory studies suggest interferon activation in lupus may be responsible for this steroid resistance. Thus, stress, changes in steroid production, and failure to suppress interferons may represent a chain of events influencing the development of lupus.

So this new study means we’re a little less unsure about the causes of auto-immune diseases. And while sufferers can’t change past life events, knowing the causes brings us closer to understanding, and to better treatments.

Laugh a little.

Can your favorite snack protect against COVID-19?

Featured Articles in Internal Medicine In the News

Can your favorite snack protect against COVID-19?

Naveed Saleh, MD, MS, for MDLinx | April 24, 2020

Natural compounds—such as flavonoids, alkaloids, polyphenols, and anthocyanins—have long been used as treatments for viral infections and immunoprotection. For instance, low doses of resveratrol, a well-known polyphenolic compound found in red wine, have been shown to stimulate and strengthen the immune system. Some researchers have also suggested that resveratrol may be efficacious against some viruses, including herpes simplex virus and Epstein–Barr virus. Like resveratrol, naturally occurring compounds in cocoa, the primary ingredient in chocolate, have demonstrated promising antiviral activity against a broader range of viruses—such as hepatitis, herpes simplex, HIV, and influenza—in clinical trials. But what about SARS-CoV-2, the devastating novel coronavirus? Could something as simple and delicious as cocoa help defend against the dangerous respiratory virus taking the world by storm?

AdvertisementWoman enjoying guilty-pleasure food

Naturally occurring compounds in cocoa, the primary ingredient in chocolate, have demonstrated promising antiviral activity against a broad range of viruses in clinical trials.

In light of the COVID-19 pandemic, it’s intriguing to wonder whether any of cocoa’s natural compounds—most widely consumed in chocolate products—may have a role in the battle against the novel pathogen. In particular, anthocyanins, which are a type of phytochemical found in cocoa, may harbor special potential in augmenting antiviral immune responses. Here’s a closer look at some recent research on the antiviral effects and immune-boosting properties of cocoa.

Immunoprotective effects

Cocoa consumption has been shown to have a positive impact on the immune system’s inflammatory innate response, as well as the systemic and intestinal adaptive responses. Basic science research has also proven that a diet rich in cocoa enhances T-cell function and leads to the formation of systemic and gut antibodies. 

In murine models, cocoa has been observed to cause changes in the lymphocyte composition of secondary lymphocyte tissues and T-cell–secreted cytokines, suggesting that cocoa may inhibit the function of T-helper type 2 cells (which contribute to the development of allergic disorders and diseases like asthma). Cocoa could also alter the function of gut-associated lymphoid tissue by modulating IgA secretion, as well as intestinal microbiota, the balance of which is essential for immune health.

Antiviral effects

Anthocyanins are antioxidants found in the cocoa seeds of Theobroma cacao,or the cacao tree. Anthocyanins are polyphenolic pigments that give leaves, flowers, and fruits their colors, and they play various roles in the life of a plant. For instance, anthocyanins in petals help attract pollinators while their presence in fruits and seeds helps with seed dispersal. They also act as feeding deterrents and protect against damage caused by ultraviolet radiation.

Among their various beneficial properties, anthocyanins are mighty antioxidants that scavenge free radicals, mitigate the effects of reactive oxygen species, and lower lipid peroxidation. As you know, during the course of infection, white blood cells are activated and free radicals are produced; the antioxidants in cocoa can neutralize these radicals.

According to the results of a review article published in Frontiers in Pharmacology, cyanidin-3-arabinoside and cyanidin-3-galactoside—the two main anthocyanins found in cocoa seeds—elicit dose-dependent activity against influenza A, influenza B, and avian influenza viruses. Such action was due to cocoa’s inhibition of the adsorption phase of the viruses.

When researchers looked more closely at human models, titers of neutralizing antibodies and natural killer cell activity against influenza A virus was heightened after ingestion of a cocoa seed extract containing cyanidin-3-arabinoside and cyanidin-3-galactoside. Furthermore, anti-HIV activity was demonstrated in cacao husk extract.

Overall, the researchers concluded that “T. cacao is a promising plant containing anthocyanins to tackle viral infections.”

Vaccine enhancement

In addition to bolstering the immune system’s functionality and defenses, cocoa may also enhance the efficacy of vaccination for some viruses. 

In one clinical trial, for instance, an experimental group consumed cocoa for 3 weeks before and after vaccination for H1N1 influenza virus. Neutralizing antibody titers against the virus were compared with those of a control group that did not consume cocoa. Although the antibodies were significantly higher in both groups, the extent of the increase was not significantly different between the groups. However, natural killer cell activity was substantially increased in the cocoa-intake group. 

“Drinking cocoa activates natural immunity and enhances vaccination-induced immune response, providing stronger protection against influenza virus infection and disease onset,” concluded the researchers.

While a vaccine for COVID-19 is still in the works, it seems that a little bit of cocoa may go a long way in amplifying the prophylactic’s efficacy once it finally becomes available. 

Dose and side effects

One admirable quality of the potential use of cocoa in the physician’s armamentarium against COVID-19 and other viruses is its favorable safety profile. While other experimental treatments like remdesivir and hydroxychloroquine carry the risk of adverse events, cocoa and chocolate consumption are relatively safe (and tasty) in most people. 

As far as how much to consume—well, that answer is not as clear cut. Studies have investigated the efficacy of cocoa-enriched diets ranging from 10% cocoa extract intake weekly to daily consumption of high-cocoa beverages (about 500 mg) to twice-daily doses of 10-g cocoa powder—all resulting in positive outcomes. Without a definitive recommendation, it’s probably a good idea to limit your cocoa consumption, given that most cocoa-containing products—like chocolate and hot cocoa mixes—are high in sugar and fat. Dark chocolate often contains a higher percentage of cocoa than milk chocolate (about 75% vs 25%), and researchers have shown that just ≤ 1 standard bar of chocolate weekly can offer a host of health benefits.

Short-sightedness in kids was rising long before they took to the screens

Part of the cause of short-sightedness is also in our genes. Shutterstock/Africa Studio

Short-sightedness in kids was rising long before they took to the screens

January 7, 2020 5.53am AEDT


  1. David Mackey Professor of Ophthalmology, University of Western Australia

Disclosure statement

David Mackey receives funding from NHMRC.


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The number of people with myopia, aka short-sightedness (difficulty seeing objects in the distance), has increased dramatically in recent years in various regions of the world.

For example, in many cities in China more than 90% of university students are living with myopia. In pure numbers this is one of the largest epidemics humanity has even seen, far greater than the obesity epidemic.

The myopia boom was first noted in 1980s in the cities of East Asian countries such as Korea, Taiwan and Singapore. The cities of China followed soon afterwards, and a similar trend is being noted in Europe.

From blur to blindness

For most people, myopia is merely an inconvenience requiring correction with glasses, contact lenses or refractive surgery.

Notably, myopia is associated with an increased risk of blindness from retinal detachment, glaucoma and myopic macular degeneration. Risk of blindness increased with worsening severity of myopia and this is a major public health concern.

Researchers and parents of children developing myopia have looked for explanations and the latest “suspect” is the use of personal electronic devices.

But the myopia epidemic in Asia preceded the release of smart phones by many years (the first iPhone was released in 2007).

New technologies – televisions in the 1960s, computers in the 1980s, laptops in the 1990s, and currently smartphones and tablets – have all been blamed for causing myopia.

As far back as the 1600s, the German astronomer Johannes Kepler, who first identified concave lenses could correct myopia, is said to have attributed his short-sightedness to all his years of “intense study of astronomical tables and so forth”. But he might well have blamed Gutenberg’s printed books (the latest technology at the time).

What’s to blame for myopia?

So what have researchers found so far?

Having parents with myopia increases a child’s risk for myopia. But children can mimic their parents’ potentially myopia-inducing lifestyle – such as near work that requires focusing on close-up objects and studying a lot inside – as well as inherit their genes.

After years of debate over whether myopia is due to genetic or environmental factors (with reading and screen use suggested), we now know it is an interaction of both genes and environment.

Myopia does not result from a single gene defect; more than 160 interacting genes contribute to the risk of myopia.

What are the environmental triggers that would explain an epidemic?

Many studies have looked at possible risk factors but only a few have come out consistently around the world: near work, years in education and lack of time spent outdoors in daylight.

Untangling the interactions is a challenge because these factors are interrelated, with children who study more spending less time outdoors.

Don’t just blame the technology

Despite decades of parents warning children, no study has shown that sitting too close to the television causes myopia.

In the past two years, five papers (1, 2, 3, 4 and 5) have looked at myopia and personal electronic devices. Some, but not all, have found an association between the amount of screen use and myopia. But this does not mean screen time itself causes myopia.

Instead of reading from books, children are reading more from screens and changing the nature of their near work. Rising rates of myopia are related to near work behaviours, rather than screen use in particular.

Children are also changing the way they use screens. The simple idea that screen use occurs indoors was completely overthrown by the Pokémon Go craze, as gamers headed outdoors with their smartphones in search of virtual treats.

In addition, we now have children using virtual reality goggles to play games or even study.

Limits on screen time

Australian guidelines recommend:

  • children under two years of age have no screen time
  • two to five-year-old children have a maximum of one hour a day
  • five to 17-year-old children be limited to two hours of recreational screen time per day.

There is no rigorous scientific basis for these time limits in relation to visual health. But a recent study showed a large percentage of children exceeded these time limits.

Potential health issues relating to screen time are diverse. Sleep, posture, level of physical activity and behavioural issues are additional reasons for concern.

Just go outside more

Unlike previous generations, most children today experience a lot of screen time. But we don’t have consistent findings for use of television, computers, tablets, smart phones or even virtual reality goggles themselves as the main cause of myopia.

We clearly need some very large, well-conducted studies, where we directly measure the use of screen time across a wide range of health issues from infancy to young adulthood.

Some cities in China are trialling scheduled time spent outdoors at school to see if it prevents or decreases the progression of myopia in children.

In Australia, we need tailored messages to encourage kids to spend more time outdoors if they are inside reading or using screens too much.

Four simple food choices that help you lose weight and stay healthy

Four simple food choices that help you lose weight and stay healthy

March 13, 2019 6.08am AEDT You don’t have to quit bread, but make sure it’s wholegrain. Shutterstock


  1. Yasmine Probst Senior lecturer, School of Medicine, University of Wollongong
  2. Elizabeth Neale Career Development Fellow (Lecturer), University of Wollongong
  3. Vivienne Guan Associate Research Fellow, University of Wollongong

Disclosure statement

Yasmine Probst receives funding from NSW Ministry of Health, Multiple Sclerosis Research Australia, California Walnut Commission and Australian Eggs. She is affiliated with the Illawarra Health and Medical Research Institute as a Research Fellow.

Elizabeth Neale receives funding from Nuts for Life, California Walnut Commission, International Nut and Dried Fruit Council, and the Illawarra Health and Medical Research Institute. She is affiliated with the University of Wollongong and the Illawarra Health and Medical Research Institute

Vivienne Guan is affiliated with the Illawarra Health and Medical Research Institute.


University of Wollongong

University of Wollongong provides funding as a member of The Conversation AU.

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It’s difficult to lose weight. And it’s even harder to keep it off. Many people achieve short-term weight-loss only to return to their previous lifestyle choices – and their previous weight – over time. This can lead to yo-yoing between weight loss and weight gain.

One of the problems is that weight-loss diets aren’t sustainable. They leave dieters feeling hungry and aren’t giving them the essential nutrients they need to maintain their long-term health.

But certain food choices can promote weight loss and provide the nutrients you need to function well and thrive. These four food choices are a good place to start.

Read more: Five food mistakes to avoid if you’re trying to lose weight

1. Whole grains help us to feel full

Many of us choose bread as part of our lunchtime meal. Switching from white to whole grain bread for your sandwich can help you feel full for longer, so you’re likely to eat less during the following meal.

The whole grain is made up of three major parts: the bran, endosperm and germ. This structure helps some of the energy to escape during the digestive process, leading to the body absorbing fewer kilojoules.

Whole grains help protect against chronic diseases including heart disease, type 2 diabetes and some cancers. The grains exert their benefits by regulating bowel function through increased faecal bulk and by feeding healthy gut bacteria.

Whole grains are easy to include in a weight-loss diet. In addition to breads, they can also be found in oats for breakfast, or popcorn for a snack.

2. Colourful veggies provide a range of nutrients

Vegetables are full of essential nutrients including folate, vitamin C, various B vitamins, potassium and fibre. They are also low in energy, providing approximately 100 to 350 kilojoules per 100g (24-84 calories per 100g).

When trying to lose weight, people tend to eat greater quantities of vegetables, but they don’t tend to choose a wide variety of vegetables beyond those they normally eat.

Read more: Eat your vegetables – studies show plant-based diets are good for immunity

To aid weight loss, make sure you’re getting a high proportion of your kilojoules from vegetables and try to have as many different colours on your plate as you can.

If you feel like you don’t have time to cook, frozen vegetables are a quick and easy option, and they are just as nutritious as fresh vegetables.

Vegetables contain essential nutrients including potassium, folate and fibre. Hermes Rivera

3. Snack on nuts

When trying to lose weight, high-fat foods are often the first to go. But while nuts are generally high in fat and related kilojoules, they are high in fibre, helping us to feel full for longer

Nuts contain a number of beneficial vitamins and minerals for our health including healthy fats, protein, various B vitamins, zinc, magnesium and other minerals. Eating nuts has been shown to be beneficial in reducing the risk of heart disease and managing type 2 diabetes.

We’re also beginning to realise we don’t absorb all the kilojoules from nuts when we eat them. In fact, research suggests we absorb up to 30% less fat from nuts than we had first thought.

Try eating a handful of nuts (around 30 grams) as a snack or adding them to your meals throughout the day.

Read more: Health check: will eating nuts make you gain weight?

4. Quench your thirst with water

Listening to your hunger and thirst signals can make a big difference when trying to lose weight.

Throughout the day, our bodily signals for thirst may be greater than our feelings of hunger. When you think you’re hungry, see if you are actually thirsty by having a glass of water first.

If you’re used to reaching for soft drink or cordial rather than the water, start the switch slowly. Replace half of each glass you drink with water and increase the water component over time. Eventually your preferences will shift.

Our bodies need water for fluid balance, body temperature regulation, cognitive performance, as well as gastrointestinal, kidney and heart function. Drinking plenty of water also improves the complexion of the skin and can reduce the likelihood of getting headaches.

Hungry? Or could you be thirsty? August_0802/Shutterstock

A final word

Although some food choices can promote weight loss and prevent subsequent weight gain, your total eating pattern is the ultimate predictor of body weight. Exercise and physical activity also plays an important role.

A healthy eating pattern for weight loss should be based on the Australian dietary guidelines, which are general recommendations for healthy eating. Aim for five serves of vegetables and two serves of fruit a day, alongside whole grain breads and cereals, lean meat and low-fat dairy. While this may sound like a lot of food, studies have shown these combinations will aid weight loss.

Although there will always be easier ways of losing weight, small changes towards healthier eating habits will help you to not only lose weight, but will provide you with the right habits to avoid regaining weight in the future.

Testosterone and Prostate cancer

Clin Endocrinol (Oxf). 2019 Sep 9. doi: 10.1111/cen.14093. [Epub ahead of print]

Another study showing that testosterone does not increase the risk of getting prostate cancer. In fact, there was a 33% reuction in prostate cancer in those men on testosterone therapy.

Association of the extent of therapy with prostate cancer in those receiving testosterone therapy in a US commercial insurance claims database.

Lopez DS1, Huang D1, Tsilidis KK2,3, Khera M4, Williams SB5, Urban RJ6, Panagiotou OA7, Kuo YF1, Baillargeon J1, Farias A8, Krause T9.

Author information

1Deparment of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, USA.2Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina, Greece.3Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK.4Scott Department of Urology at Baylor College of Medicine, Houston, TX, USA.5Division of Urology, Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA.6Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USA.7Department of Policy and Practice, School of Public Health, Brown University, Providence, RI, USA.8Department of Preventive Medicine, Norris Comprehensive Cancer Center, Gehr Family Center for Health Systems Science, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA.9UTHealth School of Public Health, Houston, TX, USA.



Conflicting evidence remains in the association of testosterone therapy (TTh) with prostate cancer (PCa). This inconsistency maybe due, in part, to the small sample sizes from previous studies and an incomplete assessment of comorbidities, particularly diabetes.


We investigated the association of PCa with TTh (injection or gel) and different TTh doses and determined whether this association varies by the presence of diabetes at baseline in a large, nationally representative, commercially insured cohort.


We conducted a retrospective cohort study of 189 491 men aged 40-60 years old in the IBM MarketScan® Commercial Database, which included 1424 PCa cases diagnosed from 2011 to 2014. TTh was defined using CPT codes from inpatient and outpatient, and NDC codes from pharmacy claims. Multivariable adjusted Cox proportional hazards models were used to compute hazard ratios for patients with incident PCa.


We found a 33% reduced association of PCa after comparing the highest category (>12) of TTh injections with the lowest (1-2 injections) category (HR = 0.67, 95% CI: 0.54-0.82). Similar statistical significant inverse association for PCa was observed for men who received TTh topical gels (>330 vs 1- to 60-days supply). Among nondiabetics, we found significant inverse association between TTh (injection and gel) and PCa, but a weak interaction between TTh injections and diabetes (P = .05).


Overall, increased use of TTh is inversely associated with PCa and this remained significant only among nondiabetics. These findings warrant further investigation in large randomized placebo-controlled trials to infer any health benefit by TTh.

My skin’s dry with all this hand washing. What can I do?

My skin’s dry with all this hand washing. What can I do?

April 14, 2020 5.48am AEST


  1. Celestine Wong Consultant Dermatologist, Monash Health
  2. Rosemary Nixon Honorary Clinical Associate Professor, University of Melbourne

Disclosure statement

Celestine Wong is a Consultant Dermatologist working at the Patch testing Clinic at Monash Medical Centre and the Royal Melbourne Hospital.

Rosemary Nixon is the Director, Occupational Dermatology Research and Education Centre, Skin Health Institute, Melbourne. The centre is a not-for-profit dermatology centre affiliated with Melbourne and Monash universities. As well as her affiliation with the University of Melbourne, Rosemary Nixon is an Adjunct Clinical Associate Professor at Monash University.


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Washing your hands is one of the crucial ways we can all help limit the spread of COVID-19.

Regularly and thoroughly washing your hands with soap and water for at least 20 seconds, or using an alcohol-based hand sanitiser, are key steps to reducing the risk.

But with all this hand washing, it’s easy to get dry skin or for existing skin conditions to flare up.

Read more: Yes, washing our hands really can help curb the spread of coronavirus

What’s happening to our skin?

The top layer of our skin (the stratum corneum) is our skin’s key protective layer. But frequent hand washing with repetitive exposure to water, soap and skin cleansers will disrupt this layer.

Over time, this leads to dry skin, further disruption of the skin barrier and inflammation.

This eventually results in hand dermatitis, or more specifically, irritant contact dermatitis.

Who’s more likely to have problems?

Irritant contact dermatitis is more common in people who perform “wet work” as they wash and dry their hands many times a day.

They include health-care workers (doctors, nurses, personal care assistants), hairdressers, food handlers, kitchen staff and cleaners. They may also be exposed to irritating skin cleansers and detergents.

But now handwashing is becoming more frequent during the COVID-19 pandemic, there may be more affected people outside these occupations.

Health-care workers, who wash their hands multiple times a day, are particularly at risk of hand dermatitis. Shutterstock

People with eczema, asthma and hay fever are also at higher risk of developing irritant contact dermatitis or experiencing a flare of underlying eczema.

Read more: Common skin rashes and what to do about them

How do I prevent hand dermatitis?

1. Soap, soap alternative or hand sanitiser?

People with eczema or who have had contact dermatitis before will have more easily irritated skin. While they can still use hand sanitisers, it’s recommended they wash with gentler soap-free washes rather than normal soap.

Soap-free washes contain non-soap-based synthetic detergents (syndets). Syndets have a nearly identical cleansing action as soap, but with the benefit of having the same pH as the skin. This means they’re less likely to remove the oils from the outer layer of the skin and are less irritating.

Soaps have a high pH and are quite alkaline. This disrupts the outer layer of the skin, allowing the soap to penetrate deeper into the skin, thus causing more skin irritation and itching.

Other people who don’t have eczema or a history of contact dermatitis should just use soap. Liquid soaps usually contain fragrances and preservatives, which can cause another type of dermatitis (allergic contact dermatitis), so opt for a plain, unperfumed bar soap.

2. Dry your hands thoroughly

Dry your hands thoroughly, including the webs of your fingers and under your rings to reduce dermatitis caused by trapped water. Skin irritation and breakdown can occur when there is excessive moisture, soap residues and water trapped between the skin and underneath rings.

Read more: Coronavirus and handwashing: research shows proper hand drying is also vital

3. Use non-fragranced moisturiser regularly

Moisturisers come in different formulations. While lotions are light in consistency and convenient to use during the day, they will require more frequent applications. Creams and ointments have thicker and oilier texture, are effective for dry hands and are best used overnight.

Fragrances can cause allergic contact dermatitis and are best avoided, where possible.

4. Use alcohol-based hand sanitiser (if you can get hold of it)

Alcohol-based hand sanitiser will reduce your skin’s contact with water, and so lower your risk of dermatitis.

Research in health-care workers shows hand sanitisers cause less contact dermatitis than washing with soap and water.

Sometimes people wrongly believe that when hand sanitiser stings on a paper cut, this means that they are allergic. But this is an irritant reaction and though uncomfortable, it’s safe to keep using it.

Which sanitiser? This usually comes down to personal preference (and what you can get hold of).

5. Use gloves

Use protective gloves when doing household chores, such as washing the dishes or when gardening.

Use cotton gloves when doing dry work, such as sweeping or dusting, to protect your hands and minimise the need to wash them.

Use washing up gloves where possible. Shutterstock

At night, moisturise your hands than wear cotton gloves. This acts like an intensive hand mask and works wonders for very dry skin. It ensures the moisturiser stays on your hands and increases its penetration into your skin.

What if my hands are already damaged, dry or cracking?

1. Act early

Treat hand dermatitis as soon as it occurs, otherwise it will get worse.

2. Apply petroleum jelly

If you think you’ve lost your nail cuticle (the protective barrier between the nail and nail fold), water will be able to seep into the nail fold, causing swelling and dermatitis.

Use petroleum jelly, such as Vaseline, as a sealant to prevent further water damage. Petroleum jelly can also be used on skin cracks for the same reason.

3. Seek medical help

If there are any red, dry and itchy areas, indicating active dermatitis, seek help from your GP or dermatologist.

They can start you on a short burst of an ointment that contains corticosteroids until the rash subsides.

Prescription ointments are likely to be more effective than over-the-counter creams because of their higher potency.

But you could start with buying 1% hydrocortisone ointment, not cream, from the chemist.

Read more: What can you use a telehealth consult for and when should you physically visit your GP?

Sometimes dermatitis can become infected with skin bacteria such as Staphylococcus aureus. Seek medical advice if you experience symptoms such as persistent soreness or pain.

You should also seek medical help if you have severe hand dermatitis not responding to home treatments.

Most GPs and dermatologists are moving to or have started using telehealth so you can consult them using a video call, minimising face-to-face appointments

Wearing face masks.


Should everyone be wearing face masks? It’s complicated

April 8, 2020 3.21pm AEST


  1. Paul Glasziou Professor of Medicine, Bond University
  2. Chris Del Mar Professor of Public Health, Bond University

Disclosure statement

Paul Glasziou receives funding from NHMRC for work on antibiotic resistance in acute respiratory tract infections.

Chris Del Mar does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.


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Should members of the public be wearing face masks during the COVID-19 pandemic? It’s a controversial question, with different countries and authorities giving different advice.

We have reviewed the results of more than a dozen randomised trials of facemasks and transmission of respiratory illnesses. We found the current best evidence suggests wearing a mask to avoid viral respiratory infections such as COVID-19 offers minimal protection, if any. Australian Academy of Science.

Conflicting recommendations

Two of the world’s major health organisations disagree on mask wearing. The World Health Organisation (WHO) currently discourages mask use:

There is currently no evidence that wearing a mask (whether medical or other types) by healthy persons in the wider community setting, including universal community masking, can prevent them from infection with respiratory viruses, including COVID-19.

WHO does recommend special masks (N95 masks or equivalent) plus other protection for health-care workers working with people who have, or are suspected to have, COVID-19.

By contrast, the Centres for Disease Control and Prevention (CDC) in the United States has recently recommended everyone wear a (cloth) mask. However, this is to prevent infected people passing on the infection, not to prevent the wearer getting infected.

Who is right? Does wearing a mask protect the wearer? Does it protect others?

Read more: Do homemade masks work? Sometimes. But leave the design to the experts

Understanding the spread

To examine this, we need to first look at how coronavirus spreads and how masks might stop it.

Coronavirus can be transmitted directly from one person to another through the air or via hands or an object. Author supplied., Author provided

There are several possible routes to infection. An infected person can cough, sneeze or breathe while within about two metres of another person, and the virus lands in the other person’s eyes, nose or mouth(1).

Another route is when an infected person coughs or sneezes onto their hand or onto a surface. The uninfected person then shakes the hand (2a) or touches the surface (2b), and transfers the virus to their own eye, nose or mouth.

It is possible that an infected person can also cough or sneeze to create an airborne spread (3) beyond the close contact range – but it is controversial whether this last route is a major means of transmission.

We don’t know how much transmission occurs by each of these routes for COVID-19. It’s also unclear how much protection a mask would offer in each case.

Current best evidence

To resolve this question, we analysed 14 randomised trials of mask wearing and infection for influenza-like illnesses. (There are no randomised trials involving COVID-19 itself, so the best we can do is look at similar diseases.)

When we combined the results of these trials that studied the effect of masks versus no masks in health-care workers and the general population, they did not show that wearing masks leads to any substantial reduction of influenza-like illness. However, the studies were too small to rule out a minor effect for masks.

Why don’t masks protect the wearer?

There are several possible reasons why masks don’t offer significant protection. First, masks may not do much without eye protection. We know from animal and laboratory experiments that influenza or other coronaviruses can enter the eyes and travel to the nose and into the respiratory system.

While standard and special masks provide incomplete protection, special masks combined with goggles appear to provide complete protection in laboratory experiments. However, there are no studies in real-world situations measuring the results of combined mask and eyewear.

The apparent minimal impact of wearing masks might also be because people didn’t use them properly. For example, one study found less than half of the participants wore them “most of the time”. People may also wear masks inappropriately, or touch a contaminated part of the mask when removing it and transfer the virus to their hand, then their eyes and thus to the nose.

Masks may also provide a false sense of security, meaning wearers might do riskier things such as going into crowded spaces and places.

Do masks protect others?

Could masks protect others from the virus that might have been spread by the mask wearer? A recent Hong Kong laboratory study found some evidence masks may prevent the spread of viruses from the wearer.

They took people with influenza-like symptoms, gave half of them masks and half no masks, and for 30 minutes collected viruses from the air they breathed out, including coughs.

Masks did reduce the amounts of droplets and aerosols containing detectable amounts of virus. But only 17 of the 111 subjects had a coronavirus, and these were not the SARS-CoV-2 coronavirus. While the study is promising, it needs to be repeated urgently.

We also don’t know how this reduction of aerosols and droplets translates to reduction of infections in the real world. If there is an effect, it may be diluted by several factors such as ill people who don’t wear a mask and “well” people who have no symptoms but are still carrying and spreading the virus.

Masks for some?

If wearing masks does substantially reduces the spread of the infection to others, what should we do? We could ask everyone with any respiratory symptoms to wear masks in public. That could supplement other strategies such as social distancing, testing, tracking and tracing to reduce transmission.

To also capture infected people without symptoms, we could ask everyone to wear masks in indoor public spaces. Outdoors is more difficult, since most people pose little or no risk. Perhaps, as we reduce restrictions, masks could also be required at some outdoor crowd events, such as sporting events or concerts.

Another possibility is a “2 x 2” rule: if you are outdoors and within 2 metres of other people for more than 2 minutes you need to wear a mask.

Mask wearing for the possibly infected, to prevent spreading the infection, warrants rigorous and rapid investigation. It could be an alternative or a supplement to social distancing, hand hygiene, testing, and lockdowns.