Monthly Archives: June 2014
Herbal preparations for the menopause: beyond isoflavones and black cohosh
Herbal preparations for the menopause: beyond isoflavones and black cohosh
- a Menopause clinic, department of Obstetrics and Gynecology, University Hospital of Ghent, De Pintelaan, 185, 9000 Gent, Belgium
- b Emeritus, department of endocrinology and metabolic diseases, University Hospital of Ghent, De Pintelaan, 185, 9000 Gent, Belgium
Complementary and alternative medicines (CAM) such as, isoflavones and black cohosh are commonly used to deal with menopausal, symptoms, but benefit a limited proportion of women. The aim of this, minireview is to summarize the evidence of the efficacy and safety of, other herbal preparations. Randomized controlled trials (RCTs) find that the extracts of Mediterranean pine bark (Pycnogenol®)), linseed, and Lepididium meyenii (Maca) reduce vasomotor symptoms. The results of RCTs of the hop flavonoid 8-pregnylnarangenin are conflicting. Animal and human studies suggest that Dioscorea villosa (Wild yam), Broccoli and linseed extracts may protect against osteoporosis and gynecological cancers but further evidence is required.
Does processed meat cause bowel cancer?
Health Check: does processed meat cause bowel cancer?
Each year around 14,400 Australians are diagnosed with bowel (colon and rectal) cancer. It’s the second most common newly diagnosed cancer after lung cancer and claims around 3,980 lives a year. The good news is that bowel cancer has a high cure rate if detected early. And there is convincing evidence…
Each year around 14,400 Australians are diagnosed with bowel (colon and rectal) cancer. It’s the second most common newly diagnosed cancer after lung cancer and claims around 3,980 lives a year.
The good news is that bowel cancer has a high cure rate if detected early.
And there is convincing evidence that you can reduce your risk of it by regularly eating foods that are high in dietary fibre, such as wholegrains, legumes, pulses, high fibre cereals, vegetables and fruit. In fact, for every ten grams of fibre you consume per day, your risk reduces by 10%.
Being physically active for at least 30 minutes a day also decreases your risk of bowel cancer.
But the other side of the risk equation is bad news for those who love a good deli meat: the regular consumption of processed meat increases your chances of getting bowel cancer.
What does the evidence say?
Red meat contains important nutrients such as protein, iron, zinc, vitamins B12, thiamin, riboflavin and niacin. But there is convincing evidence that eating more than 500 grams of cooked meat per week is risky.
The latest World Cancer Research Fund meta-analysis of 12 separate studies indicates that for every 100 gram increase in red meat a day there is a 17% increase in bowel cancer risk.
For processed meat, there appears to be no completely safe level of intake, with a meta-analysis of 13 studies finding an 18% increase in bowel cancer risk for every 50-gram increase in daily intake.
How much do we eat?
Ham and bacon are the most commonly consumed processed meats in Australia, with almost half (44%) of the population eating them once a week or more often. Other favourites include pastrami, salami, corned beef, chorizo, devon, fritz, luncheon meats, some sausages, hot dogs, cabanossi, kabana, and bratwursts.
The last National Nutrition Survey found that among adults who ate processed meat on the day of the survey, men and women ate around 40 grams and 26 grams respectively. For sausages, frankfurts and saveloys, this rose to 110 and 76 grams.
Processed meat is preserved by smoking, curing, salting or the addition of preservatives including nitrite, nitrates, phosphate, glutamate or ascorbic acid.
In Australia, mince meat has no additives and so is defined as fresh meat. Minced meats or hamburger patties are only considered processed if they are chemically preserved, which means you need to check the methods used to process these products if you eat them regularly.
What components cause cancer?
Naturally occurring food components, cooking techniques and additives in red and processed meat all impact on the mechanisms that lead to development of cancer.
Nitrates and nitrites occur naturally in plant foods as part of the nitrogen cycle between air, land and water environments. These chemicals are added to cured meats to help kill bacteria and are also produced in meat during the curing process or in the stomach during digestion of meat. Both processes play a role in the production of N-nitroso compounds that contribute to cancer risk.
It’s important to note, however, that the nitrate found in vegetables accounts for the majority of dietary consumption of the chemical. Recent reviews confirm some health benefits from naturally occurring food sources and say we need to re-examine the link between nitrate and cancer.
The haem iron in meat also promotes the formation of N-nitroso compounds. When meats are cooked at high temperatures, compounds called heterocyclic amines and polycyclic aromatic hydrocarbons are produced and also increase cancer risk.
It’s not just about the meat
Other important risk factors for bowel cancer include age (especially being over 50 years), having a family or personal history of the disease, specific genetic conditions and having inflammatory bowel disease for more than eight to ten years.
Definitive steps you can take to reduce your risk of bowel cancer include knowing your family history and participating the national bowel cancer screening program, which invites Australians who turn 50, 55, 60 and 65 to be screened.
But a simple step to reduce your risk is to change the way you think about meat: keep serve sizes of cooked red meat small – 80 grams of cooked meat up to six times a week with some meat free days. And save processed meats for special occasions
Which sugar for you?
8 November 2013, 2.31pm AEST
Health check: five sweeteners and what they mean for you
People have been eating sweet foods for eons. Fruit (fructose), milk (lactose), cane (sucrose), and honey (fructose and glucose) provide us with energy for growth and development.
But in these days, we have much more energy than we need.
The United Nations estimates that we have 13,630 kilojoules available per person, per day; government bodies recommend we limit our intake to 8,700KJ per day.
There’s been a lot of debate over the role sugar and its substitutes play in our diet. So let’s take a look at what’s on the market and what it all means for health.
Sucrose is the most common form of sugar in Australia. It’s derived from sugar cane stalks, which are juiced, dried, and processed to become raw sugar. And then it’s refined to produce white sugar.
White sugar doesn’t contain the molasses present in raw sugar, which explains its light colour. Brown sugar is, for the most part, white sugar with some molasses mixed back in. This makes it a little stickier.
Raw sugar is the least processed of the three. But nutritionally, it’s pretty much the same as white or brown sugar.
We call sugar an “empty-kilojoule” food because it’s energy dense but contains very few other nutrients.
Unless you’re eating lots of food anyway, there’s no evidence that eating sugar by itself will increase your weight. But regardless of your size, eating too much sugar can be unhealthy if you use it to replace foods or drinks that have more nutrients.
There’s also a strong link between sugar consumption and tooth decay, and between obesity and sugary-drink intake.
Fructose is central to the sugar debate, with some suggesting it has a stronger influence in obesity than other sweeteners.
This is not true; fructose is like any other sugar.
In Australia, we mostly use sucrose rather than high-fructose corn syrup, which dominates in the US food supply. So the fructose from fruit, honey, and refined fructose isn’t a significant player in our weight issues.
This natural sugar should be eaten in it’s original form (fruit, for example), and not in concentrated forms like juice and dried fruit if you’re watching your weight.
Fructose is lower in glycaemic index (GI) than other sugars, which means it’s absorbed by your body more slowly. It’s the major source of sweetness in low GI products.
Honey and syrups
Honey contains both fructose and glucose, another simple sugar that is easily absorbed by the body. In honey, the sugars remain separate, which is why it’s sweeter than table sugar (sucrose).
This means that you need to add less honey than you would sugar to achieve the desired level of sweetness when cooking food. It also means that fewer kilojoules consumed. But if you replace a teaspoon of sugar with a teaspoon of honey, you’ll actually be adding about 25% extra kilojoules.
Honey and some other syrups such as agave (from a succulent plant) contain more micronutrients than sugar. But others, like rice bran syrup, have more kilojoules and a higher GI than table sugar.
Although syrups contain nutrients that sugar does not, this doesn’t necessarily make them healthy – you can get these nutrients from other whole foods.
Steviol glucosides are intensely sweet compounds found in a little green leaf from a shrub originating in Paraguay. After purification, the resulting powder or liquid is about 200 times sweeter than sucrose.
Stevia’s main benefit is its low kilojoule content. In most stevia-based sweeteners, a teaspoon contains about four kilojoules, where the same amount of sugar has 67 kilojoules.
Like all low-kilojoule sweeteners, teeth and blood sugar levels aren’t greatly negatively affected by its consumption.
Aspartame is a non-sugar sweetener that has the ability to bind to our sweet-taste receptors. It has 200 times the sweetness of sugar, which is why we can use so little in foods or drinks to get a sweet taste.
In rat studies, excess aspartame intake has been shown to cause lymphomas and leukemias. But despite scares from a series of hoaxes, consumption of the sweetener has shown to be safe for humans.
Earlier this year, the European Food Safety Authority released the draft results of a comprehensive study showing that aspartame and its metabolites pose no toxicity concern for consumers at current levels of exposure, except in people who suffer from a genetic condition called phenylketonuria.
Logically, if aspartame contains negligible kilojoules, people who substitute it for sugar or other non-sugar sweeteners would lose weight. Unfortunately, this isn’t true.
Studies show people who consume sweeteners such as aspartame have increased appetites and tend to favour sweet foods, increasing their overall kilojoule consumption.
The consumption of sweeteners such as aspartame has also been linked to metabolic syndrome and diabetes, for reasons yet to be determined.
Making educated choices
No sugar, in itself, is bad for health, but eating too much of it, like any other food, can cause problems.
It’s important to not fall into the trap of eating much higher kilojoules by replacing sugar with other macronutrients such as protein or fat. You should also be wary of increasing portion sizes as a result of consuming “sugar-free” foods.
Even if food packaging says “sugar free”, its overall kilojoule content may be the same if table sugar has been replaced with another kind of sugar or carbohydrate, such as syrup.
A good diet centres around unprocessed foods that includes the occasional planned, discretionary treat. Instead of blindly following the latest fad, stick to sound, smart eating.
Are you eating the right sorts of fibre?
Health Check: are you eating the right sorts of fibre?
Six out of ten Australians don’t eat enough fibre, and even more don’t get the right combination of fibres. Eating dietary fibre – food components (mostly derived from plants) that resist human digestive enzymes – is associated with improved digestive health. High fibre intakes have also been linked…
Six out of ten Australians don’t eat enough fibre, and even more don’t get the right combination of fibres.
Eating dietary fibre – food components (mostly derived from plants) that resist human digestive enzymes – is associated with improved digestive health. High fibre intakes have also been linked to reduced risk of several serious chronic diseases, including bowel cancer.
In Australia, we have a fibre paradox: even though our average fibre consumption has increased over the last 20 years and is much higher than in the United States and the United Kingdom, our bowel cancer rates haven’t dropped.
This is probably because we’re eating a lot of insoluble fibre (also known as roughage) rather than a combination of fibres that includes fermentable fibres, which are important for gut health.
The different types of fibre
Eating a combination of different fibres addresses different health needs. The NHMRC recommends adults eat between 25 and 30 grams of dietary fibre each day.
For convenience, dietary fibre can be broadly divided into types:
- Insoluble fibres or roughage promote regular bowel movements. Sources of insoluble fibre include wheat bran and high-fibre cereals, brown rice, and wholemeal breads.
- Soluble fibres slow digestion, lower plasma cholesterol levels, and even out glucose uptake to the blood. Sources of soluble fibre include oats, barley, fruits, and vegetables.
- Resistant starches contribute to health by feeding good bacteria in the large bowel, which improves its function and reduces risk of disease. Sources of resistant starch include legumes (lentils and beans), cold cooked potatoes or pasta, firm bananas, and whole grains.
Resistant starches are perhaps the least well known of the different types of fibre, but they may be the most important for human health.
International studies find a stronger association with reduced bowel cancer risk for starch consumption than total dietary fibre.
Resistant starch provides a likely mechanism for this association because it promotes gut health through the short-chain fatty acids produced by good bacteria. The short-chain fatty acid butyrate is the preferred energy source for cells that line the large bowel.
If we don’t eat enough resistant starch, these good bacteria in our large bowel get hungry and feed on other things including protein, releasing potentially damaging products such as phenols (digestion products of aromatic amino acids) instead of beneficial short-chain fatty acids.
Eating more resistant starch protects the bowel from the damage associated with having a hungry microbiome. It can also prevent DNA-damage to colon cells; such damage is a prerequisite for bowel cancer.
Consuming at least 20 grams a day of resistant starch is thought to promote optimal bowel health. This is almost four times more than a typical western diet provides; it’s the equivalent to eating three cups of cooked lentils.
In the Australian diet, resistant starch comes mostly from legumes (beans), whole grains, and sometimes from cooked and cooled starches in dishes such as potato salad.
This is in stark contrast with other societies, such as India where legumes are a significant part of the diet, or South Africa where maize porridge is a staple often eaten cold.
Cooling starches allows the long chains of sugars that make them up to cross-link, which makes them resistant to digestion in the small intestine. This, in turn, makes them available to good bacteria in the large bowel.
A healthy digestive system is critical for good health, and fibre promotes digestive health. While most of us feel uncomfortable talking about our bowel movements, having an understanding of what is optimal in this department can help you adjust the amount of fibre in your diet.
There’s a wide array of bowel habits in the normal population, but many health experts agree that using tools such as the Bristol stool chart can help people understand what bowel movements are best. As usual with medical advice, if you’re concerned you should start a conversation with your doctor.
A high-fibre diet should give you a score of four or five on the Bristol stool chart, and less than four could indicate that you need more fibre in your diet. If you increase your fibre intake, you will also need to drink more fluids because fibre absorbs water.
But gut health is not as simple as just ensuring regular bowel motions. Australians are, on average, eating sufficient insoluble fibre, but not enough resistant starch, which promotes gut health by feeding good bacteria in the large bowel.
Resistant starches are fermentable carbohydrates, so you might wonder if eating more of them will increase flatulence. Farting is normal and the average number of emissions per day is twelve for men and seven for women, although that varies for both sexes from two to 30 emissions.
Nutritional trials have shown high-fibre intakes of up to 40 grams daily, including fermentable carbohydrates, don’t lead to significant differences in bloating, gas or discomfort, as measured by the Gastrointestinal Quality of Life Index.
Nonetheless, it’s sensible to increase your fibre intake over weeks and drink adequate water. You might change to a high-fibre breakfast cereal one week, change to a wholegrain bread the next, and gradually introduce more legumes over several weeks.
A slow increase will allow you and your good bacteria to adjust to the high-fibre diet, so that you aren’t surprised by changes in your bowel habits. The composition of bacteria in your large bowel will adjust to suit a high-fibre diet, and over weeks these changes will help you process more fibre.
Getting enough fibre is important, but getting a combination of fibre is imperative for good digestive health.
Most people know that eating insoluble fibre improves regular bowel movements, but the benefits of soluble fibre in slowing glucose release and resistant starch in promoting beneficial bacteria are less well known. Including a variety of fibres in your diet will ensure you get the health benefits of all of them.
What’s healthier, butter or margarine?
Health Check: what’s healthier, butter or margarine?
Butter gets points for taste; margarine for being easy to spread. But the healthiest option is not strictly called butter or margarine – it’s a “spread”. To improve the health of your heart, choose a spread with the lowest amount of saturated fat and trans fat per 100 grams. You will find this information…
Butter gets points for taste; margarine for being easy to spread. But the healthiest option is not strictly called butter or margarine – it’s a “spread”.
To improve the health of your heart, choose a spread with the lowest amount of saturated fat and trans fat per 100 grams. You will find this information in the “per 100 grams” column of the nutrition information panel.
Butter contains about 50% saturated fat, while margarine has a maximum of 20% saturated fat. The fat content of “light” or fat-reduced spreads is lowered by replacing some fat with protein and water, meaning many are much lower than 20%.
If you choose a full-fat spread (best for cooking), aim for less than 27 grams of saturated fat and one gram of trans fat per 100 grams. For fat-reduced spreads (best for bread and toast), aim for less than six grams of saturates and 0.2 grams of trans fat per 100 grams.
For a product to be called butter, it must be derived exclusively from milk and ingredients that are obtained from milk, including at least 80% milk fat. It may also contain water, salt, lactic acid producing microorganisms and flavour-producing microorganisms.
When you see products in the supermarket that are packaged up like butter, or use words such as “butter-flavoured” without specifically stating the product is butter, it’s likely they have been altered in such a way that it no longer meets the content requirements above.
To call a spread margarine, the product must be a spreadable food made of edible oils and water, containing at least 80 grams of edible oils per 100 grams. It may also include water, edible proteins, salt, lactic acid-producing microorganisms, flavour-producing microorganisms and milk products.
Some margarines contain added plant sterols and stanols, a type of fat found in vegetable oil, nuts, legumes, grains, cereals, wood pulp and leaves, which are able to reduce cholesterol absorption from the small intestine into the bloodstream. If you have high blood cholesterol, you may want to use such a product, though you need to consume 20 to 25 grams per day for the maximum effect.
As soon as the fat content of margarine drops below 80 gram per 100 grams, it cannot technically be called “margarine”. This is why the word “margarine” does not appear on labels for spreads that are fat-reduced. These are the healthiest options if you are trying to reduce your total fat and kilojoule intake.
If you are trying to lower your salt intake, check the sodium column on the nutrition information panel and aim for less than 400 milligrams per 100grams.
Cholesterol and saturated fat
Although the debate rages about the potency of specific fats in raising blood cholesterol, most Australians consume too much saturated fat from animal products. Saturated fat from foods and drinks gets manufactured in your body into low-density-lipoprotein (LDL) cholesterol, or commonly referred to as “bad” cholesterol, which then appears in your blood.
Excess LDL cholesterol that cannot be cleared by the liver ends up lining your artery walls. This makes your blood vessels hard and inflexible and they gradually become blocked. From there, it is just a matter of time before the blockage triggers a heart attack or stroke.
Saturated fat is a solid at room temperature and is the predominate fat found in the white fat in meat and dairy products, including milk, cheese, cream and butter.
Replacing butter for a spread that has a lower level of saturated fat is not the only change that can help lower your total saturated fat intake. For many Australians, the majority of their saturated fat comes from full-fat dairy, foods processed using palm oil or coconut oil, fried and fatty takeaway food, and packaged biscuits, cakes, pastries and dips.
The healthier fats are monounsaturated (avocados, almonds, cashews, peanuts, cooking oils made from sunflower, canola, soybean, olive, sesame and peanut) and polyunsaturated (omega-6 fats from sesame seed, margarine, linseed or flaxseed, sunflower and safflower oil, pine nuts and brazil nuts; omega-3 fats from walnuts, linseed and oily fish such as tuna, salmon, sardines and blue mackerel).
The one exception is trans fat. Technically it is an unsaturated fat. However, chemically it behaves exactly like saturated fat and increases LDL cholesterol. The problem is that trans fat also lowers HDL, the “good” cholesterol that carries circulating LDL back to the liver rather than it being deposited on artery walls.
In Australia, trans fat levels in spreads are among the lowest in the world. While most nutrition information panels indicate trans fat content of spreads, companies currently do not have to report it. When the nutrition information panel does not report trans fats, check the ingredients list for hydrogenated oil and partially hydrogenated vegetable oil, from which trans fats are derived.
No matter what the type of fat, they all have the same kilojoule value of 37kJ per gram. So, whether you opt for butter, margarine, a fat spread, nothing, or perhaps some avocado, hummus or tahini paste, keep an eye on the total saturated plus trans fat, and the kilojoules. And overall, try to choose foods that have a better fat quality.
Oestrogen best treatment for a dry vagina.
Management of symptomatic vulvovaginal atrophy: 2013 position statement of The North American Menopause Society
This study aimed to update and expand the previous position statement of The North American Menopause Society (NAMS) on the management of symptomatic vulvovaginal atrophy (VVA) in postmenopausal women. Clinicians can improve the sexual health and QOL of postmenopausal women by educating women about, diagnosing, and appropriately managing symptomatic VVA. Choice of therapy depends on the severity of symptoms, the effectiveness and safety of therapy for the individual patient, and patient preference. Estrogen therapy is the most effective treatment for moderate to severe symptoms, although a direct comparison of estrogen and ospemifene is not available. Nonhormonal therapies available without a prescription provide sufficient relief for most women with mild symptoms. When low–dose estrogen is administered locally, a progestogen is not indicated for women without a uterus and generally is not indicated for women with an intact uterus. However, endometrial safety has not been studied in clinical trials beyond 1 year. There are insufficient data to confirm the safety of local estrogen in women with breast cancer; management of VVA should take the woman’s needs and the recommendation of her oncologist into consideration. Research on the vaginal microbiome may lead to other therapies in the future.
Pain-free treatment for prostate cancer?
New pain-free treatment for prostate cancer? Not quite
If you or someone close to you has lived with prostate cancer, you’ve probably come across dozens of emerging treatments in your hours of Googling. One such treatment, focal therapy, has been dubbed the “new pain-free treatment for prostate cancer”. But don’t hold your breath; it’s still in its experimental…
If you or someone close to you has lived with prostate cancer, you’ve probably come across dozens of emerging treatments in your hours of Googling. One such treatment, focal therapy, has been dubbed the “new pain-free treatment for prostate cancer”. But don’t hold your breath; it’s still in its experimental phases.
So, what exactly is focal therapy? And what barriers do we need to overcome before it’s made available?
Prostate cancer is the nation’s second most common cancer, with around 19,000 new diagnoses each year. This type of cancer is multi-focal, meaning it’s found in more than one location in the prostate at a time. The largest tumour – known as the index lesion – is the main cancer that can spread to other parts of the body and lead to a reduced rate of survival.
Focal therapy targets and kills only the index cancer cells with either cryotherapy (freezing), high-intensity focused ultrasound (intense heating), laser-induced interstitial thermotherapy (intense heating) and irreversible electroporation (cell destruction). The idea is that by not treating the entire prostate, the untoward side effects from surgery or radiotherapy can be avoided.
But focal therapy works on the assumption that this index lesion is primarily responsible for cancer recurring, and that this lesion can reliably be imaged, biopsied and specifically treated.
It also assumes that targeting this lesion for focal treatment may lead to equivalent long-term cancer survivals compared with whole-gland therapies such as surgery or radiotherapy – with fewer side effects. And that if unsuccessful, these therapies can be introduced safely, without compounding side effects.
But to date, these assumptions are unproven.
Next steps for research
It’s too early to routinely recommend focal therapy to treat prostate cancer because key questions remain about its safety and efficacy. More specifically, researchers are investigating the following key areas.
First is whether the index lesion can be accurately identified. While a type of magnetic resonance imaging technique called multi-parametric MRI may be able to improve cancer identification within the prostate, it also has the potential to miss significant cancers.
Current technology does not allow for a lesion seen on MRI to be reliably seen on an ultrasound, which is technology currently used to perform the biopsy. This means there is the potential for error in both the diagnosis of a cancer (its size, position and how aggressive it is) and its subsequent focal treatment. After all, if you can’t see it, how are you going to biopsy it, yet alone treat it accurately?
Second, cancer control rates following focal therapies are largely unknown compared with standard whole-gland therapies (such as surgery). Added to this, few focal therapy reports have systematically reported quality of life outcomes such as incontinence or erectile dysfunction using validated tools. As such, the side effects of these treatments are largely unknown.
Third, the feasibility, efficacy and safety of whole-gland therapies used to salvage failed focal therapy is unknown. And the impact of leaving the non-index lesions untreated is also unknown.
Finally, with no no formal definition as to what constitutes treatment failure, there are significant challenges in determining how to monitor patients following focal therapy.
What does this mean for me?
Focal therapy isn’t a substitute for active surveillance and men with small, low-risk cancers should be reassured that their risk of cancer death over a 10- to 15-year time frame is extremely low. For these men, it’s safe to monitor the situation and have treatment only if the tumour worsens. This avoids the side effects of unnecessary treatments.
The lack of clear evidence of the superiority of focal therapy (or even equivalence) to standard therapies in cancer outcomes, and the largely unknown spectrum and severity of side effects, should not be understated. So if you do need treatment, opt for one of the proven effective therapies such as surgery or radiotherapy.
If you do wish to undergo focal therapy, it’s important you do so as part of a formal clinical trial, with appropriate ethics committee approval, consent process and with strict reporting requirements regarding outcomes and safety profile.
Is focal therapy worth studying scientifically? The answer is absolutely yes, but under formal clinical trial conditions. Is it ready for prime time? Not in 2013.