Newsletter 05, February 2007
This issue of the Good Diet Good Health Newsletter includes...
- Should we worry about soya?
- Hot tips for healthy eating
- Did you know?
- Your questions - protein powders
- Tell us what you think
- Visit our newsletter archive
1) Should We Worry About Soya?
When people talk about soya these days they usually focus on how it is produced - whether it is GM (genetically modified) or not. The biggest problem with it, however, is that it is another common food, like wheat and corn, that finds its way into a very large number of foods. It is cheap, and it is very high in protein, so food manufacturers find it very useful as an enricher and a life-extender. Soy sauce. soy flakes, soya flour, soya bran, soya oil and soya milk are easy to spot as soya products. Tofu, miso and tempeh are also made from soya. However, soya is often an unnoticed ingredient in shop-bought bakery items such as breads, rolls, cakes, pastries, doughnuts, biscuits / cookies and other products including:
- Canned meats
- Cold cereals
- Gravy mixes and stock cubes
- Desserts and ice cream of many kinds
- Formula milks
- Lecithin (unless made from egg)
- Noodles, macaroni, spaghetti, pasta
- Salad dressings
- Soy bean sprouts
- Sweets / candies
- Vegetable oils and cooking fats (mixed blends) and margarines
Soya can be disguised on food labels in many different ways: as hydrolysed vegetable protein, soy protein isolate, protein concentrate, textured vegetable protein (TVP), vegetable oil, plant sterols, or as the emulsifier lecithin.
Soya is also used extensively in agricultural feeds for intensive chicken, beef, dairy, pig and fish farming. Therefore we are very likely to be eating it indirectly whenever we eat eggs, milk, meat or fish.
So, unless we're actively avoiding it, or eating an all-natural diet, we'll probably be eating soya most days.
Well, is it a problem? Isn't soya supposed to be healthful, and in fact even encouraged for certain medical conditions?
It had been known since the early 1980s that phyto-oestrogens (plant oestrogens) such as the isoflavones in soya could produce biological effects in humans. Many health claims were made for soya on account of the isoflavones it contained, such as easing menopausal symptoms, improving bone density and protecting against certain hormone-related cancers. The rationale for the claims was that rates of these cancers, osteoporosis and menopausal problems were lower in east Asian populations, who, it was claimed, had historically eaten diets rich in soya.
However, in 2002, the British Government's expert committee on the toxicity of food (CoT) published the results of its inquiry into the safety of plant oestrogens, mainly from soya proteins, in modern food. It concluded that in there was no clear evidence supporting many of the claims made for it as a health food.
The committee pointed out that the Asian diet was not in actual fact high in phyto-oestrogens. Asians historically did not consume that much soya, and the little they did eat had usually been fermented for months. They did not consume unfermented forms such as soya milk, soya burgers or foods made with soya flour. This fact is critical, as the way soya is processed affects the levels of phyto-oestrogens. Traditional fermentation methods reduce the levels of oestrogenic isoflavones by a factor of two or three. Modern factory processes do not. Furthermore, modern strains of soya used in the West have significantly higher levels of isoflavones than Asian ones because they have been bred to be more resistant to pests (the higher levels of isoflavones make them infertile).
Toxicologist Dr Mike Fitzpatrick, who was instrumental in getting governments to start investigating the health issues surrounding soya, calculated that babies fed exclusively on soya formula could receive the oestrogenic equivalent, based on body weight, of five birth control pills a day.
Indeed, a Royal Society report on Endocrine Disrupting Chemicals in 2000 had already concluded that soya milk should not be recommended for babies and young children even when they had cow's milk allergies, except on medical advice, because of the high levels of oestrogenic isoflavones it contained. The report had also observed that mass exposure to soya isoflavones had only occurred in the past thirty years. Soya had not been part of the general food supply in the West until the 1970s, when incorporation of soya protein into processed foods became widespread.
The current advice of the UK's Food Standards Agency is that soya's potential to have an adverse effect on babies' hormonal development is still controversial, but that soya formula should only be given to infants under 12 months old in exceptional circumstances. Soya milk for babies has always been confined to a small minority in the UK. However, the situation is different in the US, where thirty to forty per cent of all infants are raised on soya formula - not least because it is given away in welfare programmes.
There are also concerns that a high intake of phyto-oestrogrens from soya can disrupt the function of the thyroid gland. This is a potential major public health concern, since the incidence of hypothyroidism (underactive thyroid) is increasing in Western populations and has been found to affect many more people than had been previously been thought. Experts now believe that hypothyroidism is seriously underdiagnosed. Untreated, it can lead to obesity, heart disease and many other chronic health problems.
Further issues surrounding soya relate to the essential fatty acids omega-3 and omega-6. The importance to our health of having the correct balance of these fats is now becoming recognized. Unfortunately, most of us take in too many omega-6s and too few omega-3s. The oil produced from soya is high in the omega-6s. As it is used extensively in the manufacture of snack foods such as crisps or chips, confectionery, deep-fried take-aways, ready meals, ice-creams, mayonnaise and margarines, it is thought to be one of the reasons our balance of omega-3s to omega-6s is so out of kilter.
To conclude, there appear to be serious questions over whether soya in the form in which we generally eat it in the West is safe, let alone a 'health food'. Before we let it become a major constituent of our diets, perhaps we should remember the following:
- Populations in the West at least have only been exposed to soya for thirty years, and there is evidence that food allergies are often the result of mass exposure to new foods which our genetic systems have not yet had time to evolve to handle.
- Those populations who have been using soya products for many years use them in limited quantities, and generally in fermented forms.
- Soya has oestrogenic effects on the body. Is ingesting these hormonal disrupters, with no way to know how much we are taking in, a good idea? How would we react if the question were turned around a little, and we were asked whether we would be happy if the government said they were going to add hormones to our food? The amount of soya found in any one soya product might be small - but what about the cumulative effect of eating it meal after meal in the many processed foods that fill our supermarket carts?
More information on the concepts outlined in this article can be found in the e-book 'Why Can't I Lose Weight - The Real Reasons Diets Fail And What To Do About It' .
2) Hot Tips For Healthy Eating
- Foods which come in a packet or tin are generally heavily processed foods. If you cannot avoid using them, then check the ingredients list. Generally, the longer the list of ingredients, the more packed full of artificial additives the product is.
- Most of us would find we eat a surprisingly narrow selection of foods, once we realize that many products are in fact the same ingredients in different form. Examples are bread, pizza crust, pie crust, pretzels, crackers, waffles, pancakes and couscous, which are all mainly forms of wheat. To ensure we get a wide variety of the nutrients we need, and to avoid the risk of creating nutrient deficiencies and food sensitivities, we should try to vary and widen our food choices, especially vegetables, salads, fruits, nuts and seeds.
3) Did you know?
Did you know that ...
- ... Milk is poorly digested by many people, and some cannot digest it at all. In order to digest the sugar in milk, which is called lactose, we need lactase. We produce this enzyme as babies (so that we can digest mother's milk) but as we get older, production declines. Some people retain enough to digest a certain amount of milk into adulthood, while others lose the ability completely.
- ... The decline of lactase production varies from individual to individual, but there are also very marked variations depending on racial origins. For instance, the incidence of lactase deficiency is around 100% for Japanese and Chinese people and certain races in Africa, whilst only 3% of Swedes and Danes are lactase deficient. The figures for Switzerland and Finland are about 17%, Greece around 75% and England around 25%. Incidence in the USA is around 10% to 73% (the lower number relates to white populations, the higher to black populations).
- ... Some forms of milk can be digested without lactase. For instance, sour milk, acidophilus milk and yoghurt may be tolerated because the lactose is already broken down, or 'predigested' by the friendly bacteria that turns milk into these products.
- ... Symptoms of deficient milk digestion include chronic or intermittent diarrhoea, bloating, flatulence or abdominal pain.
- ... Many people have a problem with milk because they are allergic to the protein it contains - this is a different problem.
4) Your Questions - Protein Powders
This is your spot. Whether it's your dietary success story, a request to cover a particular topic in a future newsletter or a question you would like answered, we would love to hear from you. Please do contact us.
Here is a question we answered recently:
- Q I'm confused about protein powders. Could you please help?
- A My carb counter says 2.24 g per 100 g for raw broccoli - I imagine the count you've got includes the fiber count, as you are in the US, and I'm in the UK (where fibre is stated separately).
Protein powders generally come as soy protein powder (protein isolated from soya beans and concentrated into a powder), whey protein powder (isolated from milk), or rice protein powder.
Soya protein powder should not be confused with soya flour (which is much heavier, being the raw soya beans milled into flour) and soya powder (somewhat lighter, milled into flour after cooking the beans). Soya powder is sometimes sold as 'dried soya milk'.
Protein powders often contain added sweeteners, flavors or fillers, so read the labels carefully, particularly if you wish to avoid unnecessary carbohydrates. Protein powders are more or less interchangeable in recipes, as long as you don't use sweetened or flavoured ones for savoury recipes.
5) Tell Us What You Think
Your opinions matter to us. If there is something you particularly like or don't like about our newsletter or website, please let us know.
6) Visit Our Newsletter Archive
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With best wishes for your continued good health
Founder Director, Good Diet Good Health.com
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