I am no fan of processed foods generally. And many processed foods, I think, masquerade as something quite healthy on the basis of being low or absent in something supposedly unhealthy. Not so long ago, I highlighted the not so nutritional aspects of the mold-organism-taken from-soil-and-fermented-with-sugar-based product that is Quorn.
This food, in a dizzying array of incarnations, portrays itself as a healthy alternative to meat. And some store is made of the fact that, compared to meat, it is lower in supposedly toxic substances such as saturated fat and cholesterol. However, seeing as the evidence suggests these fats are quite benign, then the assumed healthiness of Quorn products looks, in my view, very suspect indeed.
Today, I see, that meat-substitute foods have had a bit of a kicking in the press. See this article in the Daily Mail (UK) as an example. An organisation called Consensus Action on Salt and Health has revealed that many veggie-sausages and burgers are stacked with salt.
This body is keen, it seems, to be aware that just because a food is meat-free, that doesn’t mean it’s automatically healthy. I couldn’t agree more. Firstly, the evidence does not support the notion that meat and its fatty constituents are the killer foods some would have us believe them to be. Also, even if they were, the mere absence of them does not make a highly processed, salty food based on quite unnatural ingredients a ‘healthy’ alternative.
In addition to Quorn, the other major base product used in meat substitute foods is soy. It’s a food that has managed to get itself quite a wholesome, healthy reputation. One angle here, has been for its manufacturers to draw our attention to its ability to reduce cholesterol levels. I don’t know if that’s true or not, and I don’t very much care anyway seeing as taking dietary steps to reduce cholesterol has not been shown to have broad benefits for health.
So, the health claim regarding cholesterol seems to lack substance, But is there anything else about soy that might be positively detrimental to health? Well, for a start, soybeans are also rich in a substance known as phytic acid ” a compound which impairs the absorption of a range of minerals including calcium, magnesium, iron and zinc. Phytic acid is also found in grains, but soybeans seem to be especially rich in this anti-nutrient [1]. Unfortunately, cooking does not seem to destroy phytic acid, though levels of this compound can be reduced (though not necessarily eliminated) by fermentation to make foods such as tempeh and miso.
The food industry has contrived to contrive soya into a huge range of processed foods by converting raw soya beans into something known as soy protein isolate (SPI). Production of SPI takes place in factories where a slurry of soy beans is treated with acid and alkali solutions to get the protein to precipitate out. In this process the product can be tainted with the metal aluminium (aluminium exposure has been linked with an increased risk of degeneration of the nervous system and Alzheimer’s disease). The resultant protein-rich ‘curd’ is spray dried at high temperature to produce a powder. SPI may then be heated and extruded under pressure to make a foodstuff known as textured vegetable protein (TVP). SPI and TVP will often have monosodium glutamate (MSG) added to it to impart a ‘meaty’ flavour before it is fashioned into products such as vegetarian burgers, sausages and mince.
Versatile SPI may be, but it is actually a very heavily processed food. What are its effects on health? Certain toxins found in soy, including substances that inhibit digestion are known to remain in SPI [2]. Animal experiments that suggest that the eating of SPI can lead to a deficiency of a range of nutrients including calcium, magnesium, manganese, copper, iron and zinc [3].
Soy is also rich in hormone-like molecules known as phytoestrogens, and it their presence in soy which has led to the other common claim made for soy: that it can help protect against breast cancer. However, the evidence in this area is very mixed, and there is simply no clear evidence which supports the role of dietary phytoestrogens in the prevention of breast cancer [4].
Also, it is possible that plant compounds that mimic oestrogen may actually have an adverse effect on health. It is known, for instance, that high levels of oestrogen have been associated with an increased rate of mental decline associated with ageing. It is interesting, then, that one study has found a significant statistical relationship between the eating of tofu and accelerated brain ageing [5].
One of the phytoestrogens in soy has been shown to have the potential to poison the thyroid gland. Feeding rats the soy phytoestrogen known as genistein has been found to cause irreversible damage to enzymes that make thyroid hormones in the body [6]. In humans, this effect could conceivably lead to low thyroid function (hypothyroidism), which can cause symptoms which include weight gain, fatigue, depression and constipation.
With all this in mind, does soy really deserve healthy reputation some would have us believe it deserves? I don’t think so.
During the weekend I delivered a lecture in Berlin. One of the questions I got asked after the lecture was about the nutritional attributes (or otherwise) of soy. Sometimes, when asked about a specific food I deliver what might be seen as a verdict first, and then qualify and justify it with some science. I went for this approach at the weekend. My response to the question about soy started: It’s a shite food, really�. Sometimes, it’s best just to say it how you see it.
References:
1. El Tiney AH. Proximate Composition and Mineral and Phytate Contents of Legumes Grown in Sudan Journal of Food Composition and Analysis, 1989;2:67-68
2. Rackis JJ, et al. The USDA trypsin inhibitor study. I. Background, objectives and procedural details,” Qualification of Plant Foods in Human Nutrition, 1985;35
3. Rackis JJ. Biological and physiological Factors in Soybeans,” Journal of the American Oil Chemists’ Society, January 1974, 51:161-170
4. Gikas PD , et al. Phytoestrogens and the risk of breast cancer: a review of the literature. Int J Fertil Womens Med 2005 50(6):250-8
5. White L. Association of High Midlife Tofu Consumption with Accelerated Brain Aging. Plenary Session 8: Cognitive Function, The Third International Soy Symposium, Program, November 1999, page 26
6. Doerge DR. Inactivation of Thyroid Peroxidase by Genistein and Daidzein in Vitro and in Vivo; Mechanism for Anti-Thyroid Activity of Soy presented at the 1999 Soy Symposium in Washington, DC National Center for Toxicological Research, Jefferson
Unless you have kidney disease, salt (or sodium) isn’t a problem – just another urban myth.
However I do try to avoid soy
Plus, processed foods are low in potassium (processing removes potassium). So likely, it isn’t the high sodium content of processed foods that is the problem, it is the imbalance in the sodium/potassium ratio that creates a problem. Potassium is found in fresh foods. Far better to get potassium from fresh foods than potassium supplements, IMO.
I wonder how many people who promote soy products as healthful foods would continue to do so if they had any idea how things such as TVP are actually made. Your description of its making should be enough to discourage anyone from eating something that comes into being through such a disgusting-sounding process. I felt slightly nauseous just reading about it. And yes, I have avoided foods made with soy for some time. I read ingredient labels and put anything back on the shelf with soy or corn syrup in it.
As a vegetarian, I rely quite heavily on Quorn & soy products such as tofu for protein. What you would recommend as alternatives?
My seven-year-old daughter is a terribly picky eater. We’ve tried everything, including hypnotherapy, but she simply will not eat most meat, & fruit & vegetables only in pûrée or compote form. However, she loves organic tofu with herbs and organic soy sausages which I thought were at least one healthy option she would eat. If I now have to eliminate this too, what can I possibly feed her?
Reading the comments above and Dr Biffa’s comentson processed soy I come to the conclusion that a diet rich in a good mix of unprocesed food is the only way forward.
totally agree with Emma and Daisy.
We can eat beans and pulses, but to some extent quorn, and certainly soy form a very important part of a (mainly) vegan diet.
I think its important to remember that meat etc are not always excluded from the diet for health reasons
Dr Briffa, I have been using soya ‘milk’ for a couple of years, started to combat hot flushes. I only have it in one or two mugs of tea a day. I am also hypothyroid, my thyroid having packed up at the beginning of the 80s – so, would you advise me to stop using it?
Any concerns about the levels of actual oestrogen in Cow’s milk?
If you exclude meat for whatever reason its always going to be more difficult to get all the required nutrients. As a vegetarian or vegan its up to you to be cluey about the best sources of protein. But surely you didn’t become a vegetarian or vegan so you could eat fake, processed look-alike meat products. Eat your vegetables, fruit, nuts, seeds, spirulina etc.
Phytic acid can also be considered to have health benefits. In animal studies phytic acid showed a protective action in carcinogenesis. This action could be explained by its mineral chelating potential. Some studies suggest that phytic acid acts as anti-cancer agent by reversing the proliferative effects of carcinogens.
Regarding the study on accelerated brain ageing, in contrast Seventh Day Adventists, many of whom consume soyfoods their whole lives, have less dementia in old age than the general population. Certainly, the cultures where soyfoods are consumed on a regular basis don’t see corresponding raises in levels of Alzheimer’s such as Japan or China. A doctor practising in Hawaii followed up on this study by comparing the levels of aluminum in island and mainland tofu and found much higher levels in the island sources. Was it the aluminum that was causing this contrast to other parts of the world?
james h you wrote “Certainly, the cultures where soyfoods are consumed on a regular basis don’t see corresponding raises in levels of Alzheimer’s such as Japan or China” this is a total myth the fact is that Asian cultures do not consume soy as a meat replacement only as a condiment. So they would only consume about one twentieth of the soy westerners would eat & most of their consumption is of the fermented type as asians learnt thousands of years ago that soy is not a food one should consume in great quantities & it’s greatest value is as a soil improver not a food & fermenting it takes out most of it’s toxic qualities for more information see http://www.soyonlineservice.co.nz
a great site that tells of the real scientific knowledge as opossed to the advertising myths surrounding this toxic waste product!
no plant can supply the wonderful nutritious benefits of meat & animals deserve to be treated with respect & honoured for their sacrifice not treated as a comodity. to deny your body their precious gift out of some misguided sense of moral outrage is to deny their purpose for being – animals after all are food for other animals all over creation. it doesn’t make it morally wrong to kill & eat them but some of our practices can be highly questionable, maybe your energies could be going towards this, instead of pretending we can exist without eating them.
Helen the oldest Okinawa Japanese, average 1-2 servings of soy each day. They have traditionally eaten regular but moderate amounts of whole soyfoods such as tofu, soymilk, and edamame, as well as the fermented versions, tamari, and miso. Oh yes and I agree the Okinawa Japanese eat meat too, but all I am arguing here is they eat this to quote you “toxic waste product” and survive quite well.
I can only agree with Dr Biffa re the highly processed soya which I would avoid. However it is wrong to scare people who are eating tofu and soya milk.
The site you mention appears totally bias. Towards the end of you post, you seem to have got quite emotional. I have lost some of the arguments, but yes people can live without meat. The vegetarian Seventh Day Adventists demonstrating this living long and productive lives.
What about soy milk Dr Briffa? Is it better than cow’s milk?
“The claim that vegetarians have lower rates of cancer compared to nonvegetarians has been squarely contradicted by a 1994 study comparing vegetarians with the general population.7 Researchers found that although vegetarian Seventh Day Adventists have the same or slightly lower cancer rates for some sites, for example 91 percent instead of 100 percent for breast cancer, the rates for numerous other cancers are much higher than the general US population standard, especially cancers of the reproductive tract. SDA females had more Hodgkins disease (131 percent), more brain cancer (118 percent), more malignant melanoma (171 percent), more uterine cancer (191 percent), more cervical cancer (180 percent) and more ovarian cancer (129 percent) on average.”
http://www.westonaprice.org/basicnutrition/vegetarianism.html
The Seventh Day Adventists may live longer lives because their lives are less stressful and they have the support of their community.
Daisy unless your child is in imminent danger of starvation, I recommend letting her eat what she chooses… and if that is nothing… then eventually she will get hungry enough to eat what is available. What do you think would happen to kids who were ‘picky eaters’ historically? They’d learn to eat what was available. Have you had a medical exam for her? Maybe there is some reason that solid foods bother her, somewhere between the teeth and elimination system. The inability to eat ‘real food’ is not going to be good for her long term growth patterns and health surely. That verges on something psychiatry might be useful for; imagine if the rest of her life the only thing she can eat is a specialized tofu and not solid food? I’d look to medical professionals (rather than hypnotherapy–which I respect and am extremely conversant with) for something this serious. Just my two cents.
This blog is one-sided and misleading, as well as being particularly unhelpful to those who choose not to eat meat for ethical reasons.
For those who want a far fuller consideration of soya (which includes the good aspects and legitimate criticisms) try these pages:
http://foodrevolution.org/what_about_soy.htm
http://eatkind.net/wholesoystory.htm
And for anyone who is concerned about how to provide good quality plant-based nutrients (with or without soy), the vegan society has an excellent and informative website and has always responded quickly to my queries: http://www.vegansociety.com
This crack pot author seems to have a bee in his bonnet and has no qualification to really preach in my opinion- and is in essence talking drivel.
The basics:
If you choose the lowest salt non meat sausage for example (i.e use your brain/ common sense/ read the label) you are doing better than the equivalent standard supermarket pork or beef sausage- that’s just obvious.
Also just because something is ‘processed’ doesn’t mean it’s a ‘frankenstein food’ and the word ‘processed’ is, in this article, just used to spread worry unduely. Tofu /soya based products have been refined and processed for thousands of years without much change.