Too Much Soy May Neutralize Benefits

Hi,

There is a Norwegian study that says soy treated at a very high temperature results in a soy product that is not so beneficial.

Study: 

Lars Henrik Høie, M.D.: Cholesterol lowering effects of soy protein, and how denatured protein may increase the risk for cardiovascular disease, Institutt for helse og samfunn, Universitetet i Oslo, januar 2011.

article excerpt:

Harmful soymilk Soy and dairy products with long shelf life are heat treated. They may increase the risk factors for cardiovascular disease by nearly 20 percent, according to a Norwegian doctorate.

http://www.forskning.no/artikler/2011/januar/275961

Could the soy used in the study in the video be of the type that is treated at a very high temp? Would home made tofu, soy milk etc perhaps show a different result?

Thanks

I noticed that you were “advertising” for “Silk” soy milk.  You should know that “Silk” has contributed to the ”Monsanto” side of the GM Labeling proposition on the ballot in California.  They did not give funds to the “Organic” Labeling Promoters but gave hundreds of thousands of dollars to campaign against labeling Genetically Modified Foods so we as consumers can make a choice.

“Silk” is not alone and a lot of “industrial organic” companies have contributed to the “Monsanto” side of the proposition.  I just think your followers should be aware that not all so called “organic” health food is what it appears.  I find it appalling that companies like the producers of “Silk” play off the market to “health finders” but do not share an ounce of the philosphy and the goals of those trying to eat a healthy diet.   

Thank you for this addressing this issue. I don’t eat nearly 7 to 18 servings of soy a day but my IGF – 1 is 198!  I have been vegan for decades.

I am trying now to find a doctor who will order up the binding factory test. My regular doctor thinks it is an unnecessary test and had his staff person tell me to go to a specialist.

He is the guy who didn’t even know what IGF-1 was!

Ann
Annapolis

Are soy based products harmful if eaten 2-3 times per week? How many grams of soy per day are beneficial? How much soy is detrimental?

R Ian Flett: I think that this is a useful comment and I am inspired to share my perspective on this topic.

I think that people like you and the person by the alias ‘DT’ are contributing more value to this website than those who simply beat the drums behind Dr. Greger as if he is some kind of vegan rock star. Even though I think that Dr. Greger is doing a good job making relevant articles available and providing entertaining (and often informative) videos, we must remind him from time to time to analyze the facts dispassionately and provide fair evaluation of limitations that are inherent in studies. He should provide the same level of critique to studies that support veganism as to those that oppose veganism.

Presumably, many of us are not just tuning into this website to get our morning dose of vegan validation. Hopefully some of us are trying to better understand the science of plant based diets. We musn’t forget that, to be understood, science must be always be challenged.

Viewing your critique of scientific studies in the abstract, I think that studies are always going to have limitations – they just can never control all variables. As you point out there is always the possibility of a hidden variable, which explains any correlation. Another limitation is that studies typically only compare one dietary intervention (e.g. vegan diet) against the standard of what the general population eats. Differences seen obviously say little about what is optimal, since the control group (e.g. SAD diet) is so backward that virtually any reasonable intervention would show some improvement. For example, if a comparison is made between the health status of people who ate hot dogs without the bun to those that ate hot dogs with the bun, an improvement may be found by dropping the bun. But, it would be ridiculous to conclude from a study like this that eating hot dogs without a bun is somehow optimal.

Therefore, I think the best studies can do is provide clues, which need to be explored by physiological research.

Instead of simply focusing on inconclusive studies, I would like to see this website develop and critically evaluate the key mechanistic threads of reasoning in favour of plant-based diets, for example:

1- We have seen that plant-based food are packed with more antioxidants than animal-based foods:
http://nutritionfacts.org/video/antioxidant-power-of-plant-foods-versus-animal-foods/

It would be useful to learn more about what physiological conditions affect whether the antioxidants reach the cells of our body. We should try to better understand what limits absorption and whether the antioxidants are actually active within cells. What diseases do antioxidants impact and what conditions affect this?

2 – We have also learned that plant-based diets have far lower levels of chemical pollutants:

http://nutritionfacts.org/topics/persistent-organic-pollutants/

Since we are all living in a chemical soup, clearly our bodies are somewhat resilient to pollutants. I have always wondered what concentration of pollutants actually make a difference. So I think we need data to better appreciate what concentration of pollutant get absorbed by our bodies and the specific role played by these pollutants in shifting the balance from health to disease. I think this question is also important in connection with organic versus conventional farmed foods.

3- Another complex topic is nutrient synergies. One of the themes of this website has been that eating produce is better than taking the equivalent nutrition in the form of pills. I think more research is needed to understand why this happens. For the same reason that vitamin C in fruits may be more effective than eating vitamin C pills, some foods like fish may seem to provide health benefits in certain studies, because the whole is greater than the sum of its parts. So simply dismissing fish on the basis that it has high concentrations of pollutants may be incorrect from a physiological perspective.  I don’t eat fish, but I still want to know why some studies suggest health benefits. Is it possible that this is because of synergistic effects? Or is is simply do to anti-inflammatory effects relative to SAD, as usually suggested.

Anyway, I hope that Dr. Greger reads our questions and considers them when formulating new videos.  I would be highly interested in further comments on any of these topic areas.

Here’s another variable that I had previously missed that might make even more sense out of the IGF-1 issue relating to a plant based diet. 
It seems that low dietary methionine reduces IGF-1 signalling and so, in turn, methionine-reduction’s effects are correlated with calorie-restriction’s effects.http://www.oasisofhope.com/media/pdf/met_vegan.pdfOnce you consider that calorie restriction’s role in longevity may be dependent, not really on total calories, but rather on the total intake of methionine (less is better), then a new perspective emerges. Quoting http://www.nutritionj.com/content/10/1/107In summary, neither carbohydrate restriction nor lipid restriction appear to be responsible for the life extension caused by CR, while approximately half of the life extension effect of CR seems to be ascribable to protein restriction. A wealth of evidence indicates that methionine restriction might account for most or all of the life-extending benefits of protein restriction. Fortunately, a methionine-restricted diet is both feasible and tolerable, suggesting that it might be an attractive alternative to CR for those seeking the health-enhancing properties of such a plan. However, because the evidence provided above has been generated using animal models, further work involving human test subjects is necessary before firm conclusions can be made.Vegans have the lowest dietary-style intake of methionine because meat, fowl, fish, dairy and egg proteins are relatively high, while plants are low. There is a surprisingly high amount of statistical evidence to support the negative role of methionine in longevity, despite it being an essential amino acid. Plant proteins are generally much lower in methionine than animal proteins. This could also explain why fish never seems to benefit more than thrice a week as the assumed omega 3 benefits may offset by increased methionine. Recent Swedish studies indicateded that daily fish consumption increased ischemic strokes in women.Possibly better would be the fish oil capsules, although evidence varies widely. High omega 3 veggies, such as flax, may be even better still. Fish products now have the increasing problem of contaminants, the latest of which is plastics getting into their food chain even down to the plankton level.

Just a note. Perhaps lowering IGF1 levels might not seem the only way that soy protein might decrease cancer growth. In the China Study, p60, T. Colin Campbell reported on the effect of different kinds of high protein diets on foci response in rats. He saw a huge foci response with 20% casein, butt virtually no response with gluten protein – but also soy protein.  In this case soy protein, even if very high amounts, did not promote cancer growth any more than wheat protein did, while milk protein acted as a supercharged fertilizer increasing cancer growth many fold. In these experiments plant protein – including soy protein – at least in rats -, did not promote cancer growth even at high levels of intake.