Tempeh and Seitan?

[FrederickSebastian]

Hi,

 

I am working on becoming a CR dieter and also being lacto-ovo vegetarian but I'm wondering -- do tempeh and seitan have any place in a CR diet as a meat replacement/source of protein. I am worried because seitan is wheat gluten and you hear so many bad things about gluten nowadays. Also, tempeh is fermented soy and I hear so many bad things about soy...

 

Do these have any place in a CR diet and if so how much should I eat? every day? in moderation? now and then?

 

Just curious...

[TomBAvoider]

If you don't have gluten sensitivity, or if you are not fasting, then there is no real reason I'm aware of one should avoid gluten. You can get tested for gluten sensitivity - it's a very cheap test that your PC can order. 

As to soy - this is risky. Serious possibility of vascular dementia with regular consuption. Here is a very well designed study, very convincing, and never refuted despite various attempts:

https://www.ncbi.nlm.nih.gov/pubmed/10763906

[mccoy]

I beg to slightly differ from Tomb's drastic conclusions.

The study should have been confirmed by further studies. If not, we all know that a single scientific study cannot be accepted as conclusive evidence in view of the overall health benefits of soy products ingested in not excessive amounts.

Also, if I'm not wrong, the study focuses on tofu products, where some additives may be used, the critic on such a study is that the curding agent may have been deleterious, not tofu itself

 

Edited October 19, 2019 by mccoy

[Todd Allen]

15 hours ago, FrederickSebastian said:

Do these have any place in a CR diet and if so how much should I eat?

There is much variation in how people respond to foods.  You can learn what works for you through deliberate testing and monitoring.  Establish a consistent base line diet tracking how you feel and perform.  Then add in a daily serving of seitan for a couple weeks and see if anything noticeable changes.  If not you probably don't have an issue with it or gluten.  If you suspect an issue eliminate seitan for a couple weeks and then try it again.  If you see a repeatable pattern then causation is likely.

[TomBAvoider]

And I disagree with mccoy's disagreement. His "additives" and "curdling agents" excuse is the one I referred to when I wrote about various attempts to refute the study (the usual excuse is "aluminum in the preparation process" - but that excuse has been thoroughly debunked. To repeat: there has been NO successful objection to the study. None! There were many threads on the topic of tofu, going back all the way to the email list with extensive discussions, so if anyone is interested, they should search for them. And while more studies are always welcome, there is no reason why we should not accept a study that is extremely well designed and very convincing (especially the observed dose-response effect). Or you can gamble your brain on it. Personally, I won't. It's not that I avoid tofu altogether, just that it is not a regular part of my diet, it's a once in a while, occasional thing. YMMV.

[mccoy]

TomB: one single study in 2000, has it been repeated? It has not been refuted but has it been confirmed?

[TomBAvoider]

No, but since it has NOT been refuted, it is still extremely important. That's how science works. For example if there's a mathematical proof, you don't say "yes, it's PROVED, but can you prove it again?" The burden is on the other party - those who deny. If the study showed very strongly how tofu is damaging to the brain, and someone objects, then the proper procedure is to prove the objection, not to cry out "prove it again!". Disagree? Show a study that disproves it. Absent that, the study STANDS. It stands, because no objection has been successful - that's how a study stands. Basic. So to now ignore it, because someone says "well we tried to disprove it for 20 years and couldn't - but we still won't accept it, prove it AGAIN!". If someone doesn't like the conclusions of a study, the proper way to object is to state a counterproof - if you don't have one, guess what, the study STANDS.

[Sibiriak]

Epidemiological studies are  not the same as  purely logical mathematical proofs.  They are rarely "refuted"  outright.  Generally they are subject to criticism of greater or lesser cogency related to methodological issues,  possible confounding factors,   doubts raised by other lines of evidence, etc.

Regarding the study in question,  here are a few examples of critical assessments:
 

Brenda Davis  Vesanto Melina,  "Becoming Vegan: Comprehensive Edition"

Quote

  In 2000, a study that followed more than 3,000 Japanese adults living in Hawaii reported that those who ate the most tofu during the period between their mid-40s and mid-60s were 2.4 times more likely to experience a decline in cognition during their 70s to 90s.287 The results sent shock waves through the vegan world.

Unfortunately, the headlines didn’t mention that the data on food intake was collected only twice— during the participants’ mid-60s (baseline) and their early 70s— and for a limited number of foods. Cognitive function wasn’t measured until about twenty years later. It’s possible that food choices made during this period of twenty years played a larger role than the tofu eaten decades before. There was also some suggestion that those with higher midlife tofu intake came from poor immigrant families that were less able to provide adequate nutrition during the early years of childhood.

Regardless, the findings generated interest within the scientific community, as well as further research. In a study of Japanese-American seniors (65 and older) released the same year, tofu intake was very weakly linked to lower cognition scores, but only among women using estrogen replacement therapy, and only at baseline. 288 After two years of follow-up, it turned out that tofu consumption wasn’t associated with cognitive decline in men or women (regardless of the use of hormone replacements).

In 2008, a study from Indonesia reported that tempeh consumption was associated with slightly improved memory scores, while tofu consumption yielded slightly reduced scores. The authors suggested that the most plausible explanation for the difference was due to production methods used in Indonesia; formaldehyde was commonly added to tofu but not to tempeh. 289 In 2010, the same investigators revisited the tofu/ cognition relationship in participants between the ages of 56 and 97. They found that eating both tofu and tempeh improved immediate recall in relatively younger participants with an average age of 67, but that the association was no longer significant in older participants who averaged 80 years of age.

Although these later studies allayed the fears of some consumers, other studies have provided additional reassurance. To date, approximately thirteen clinical studies have tested the link between soy and cognition. Of these, ten studies found soy consumption beneficial291– 300 and three reported that soy consumption is neither beneficial nor detrimental. 301– 303 None of the clinical trials confirmed a causative effect between soy consumption and cognitive decline.   

 

Harvard School of Public Health -- Straight Talk About Soy

 

Quote

Memory and Cognitive Function

Menopause has been linked with changes in mood and memory impairment. Long‐term low levels of estrogen in women can reduce the number of estrogen receptors in the brain that are necessary for specific cognitive functions like memory and learning. [26] The soy isoflavone, daidzein, has been hypothesized to reduce decline in cognitive function or disease processes related to cognition and behavior. Thus, research has raised the possibility that eating soy foods might help prevent age-related memory loss or decline in thinking skills. [27]

Trials have yielded contradictory results, with some showing a benefit with soy isoflavone supplementation [28, 29] and others showing no benefit. [30-32] A review of 13 randomized controlled trials found that in about half of the studies, isoflavone supplementation had a beneficial effect on cognition in older men and women compared with controls, including improvements in attention, information‐processing speed, and memory. However the results overall were mixed, with other studies not demonstrating a benefit. This may have been due to differing dosages given or the types of cognition tests used. [26]

One large study in men found a detrimental effect on cognitive function. In a prospective cohort study of more than 3,700 Japanese-American men living in Hawaii, the highest intakes of tofu (eaten almost daily) at midlife ages were significantly associated with greater cognitive impairment and brain atrophy in late life compared with men with the lowest tofu intakes (almost never eaten). [33] However, the actual number of men eating very high amounts of tofu was small, and past dietary information was collected by relying on the participants’ memory, some of whom may have already experienced cognitive decline. Because of this, the researchers stated that the findings were too preliminary to make recommendations. [34]

 

Soy Part 1—Main Controversies   by Jack Norris, RD

Quote

Dementia

The 2000 Honolulu-Asia Aging Study linked soy with lower cognitive function and brain shrinkage. Here’s a more thorough review of the research on soy and mental cognition.

There’ve been twelve short-term clinical trials lasting one week to a year. Nine show soy to be helpful (9, 10, 11, 12, 13, 14, 15, 16, 17), while three have shown soy to be neutral (18, 19, 20).

Epidemiological studies (unlike clinical trials) examine patterns of soy consumption and cognition in specific populations. One such study found tempeh (a fermented soy food) to be associated with improved cognition (21). Three reports from epidemiological studies have associated tofu with reduced cognition in some groups (21, 22, 23), but increased cognition in another group (24), and neutral in others (23, 24). The harmful findings for tofu in the epidemiological studies are likely due to confounding caused by the fact that people of lower economic status have traditionally eaten more tofu in Asian cultures as well as the fact that some Indonesian tofu has been prepared using formaldehyde.

The research as a whole provides little cause for concern.

 

Edited October 19, 2019 by Sibiriak

[Saul]

41 minutes ago, Sibiriak said:

Epidemiological studies are  not the same as  purely logical mathematical proofs

Very true.  you cannot "disprove" a theorem that has been correctly proven.

Biological "proofs" of results in studies are just strong correlations that have a high probability of being likely on the basis of standard statistics.

41 minutes ago, Sibiriak said:

The harmful findings for tofu in the epidemiological studies are likely due to confounding caused by the fact that people of lower economic status have traditionally eaten more tofu in Asian cultures as well as the fact that some Indonesian tofu has been prepared using formaldehyde.

Thanks for looking this up, Siberiak.

The excessive concern over soy in the CR Society dates back to the old CR List; Michael Rae (perhaps our most brilliant member) posted the 2000 Honolulu-Asia Aging Study to the Society, and showed a lot of concern.  I was always skeptical.  (I suspect that Michael was too, since he was very unhappy when no tofu was available for vegans at the last CR Society meeting.)

I encourage people to read the whole of Siberiak's post.

  --  Saul

Edited October 19, 2019 by Saul
typing error

[Ron Put]

I thought the soy scare nonsense died a long time ago and only meat industry shills would bring it up now and again on social media....

Soy and Health Update: Evaluation of the Clinical and Epidemiologic Literature

"19. Conclusions

Soyfoods have become increasingly popular in non-Asian countries. Their versatility allows them to easily be incorporated into Western diets and therefore provides a convenient way to exploit the nutritional advantages of legumes, which often play an underutilized role in North America and many European countries. However, the macronutrient composition of the soybean is different from other legumes. Also, soy protein is higher in quality than other legume proteins and the soybean is a good source of both essential fatty acids. Soy protein also directly lowers circulating LDL-cholesterol levels and may also modestly lower blood pressure. Replacement of commonly-consumed sources of protein in Western diets by soyfoods may also lead to a favorable change in the fatty acid content of the diet.

The most distinctive aspect of the soybean is its high isoflavone content. Isoflavones are proposed as having a number of health benefits although not surprisingly, the degree to which the evidence supports these claims varies. For example, there is solid evidence in support of isoflavones alleviating hot flashes and improving arterial health in menopausal women whereas the evidence that they reduce risk of breast and prostate cancer, not surprisingly, is more preliminary. Concerns that the estrogen-like properties of isoflavones produce untoward effects in some subpopulations, such as postmenopausal women, are not supported by the clinical and epidemiologic research. Evidence indicates soyfoods can be safely consumed by all individuals except those who are allergic to soy protein, which is relatively uncommon in comparison to the number of individuals allergic to many other commonly-consumed foods [436,437,438].

When adding soy to the diet it is important to consider the overall nutritional quality of a particular soyfood since many Westernized soyfoods include a variety of non-soy ingredients. There are no formal recommendations for soy intake beyond the 25 g/day soy protein established by the US FDA as the threshold intake for cholesterol reduction. However, population and clinical studies involving adults suggest benefits are associated with approximately two to four servings per day. Ideally, soyfoods are incorporated into the diet by displacing less healthy foods and as part of an overall healthy diet designed to lower risk of chronic disease such as the approach represented by the portfolio diet."



And here is something to preempt the GMO scaremongering:

Will GMOs Hurt My Body? The Public’s Concerns and How Scientists Have Addressed Them

As to gluten, unless you have an allergy, it's fine. I personally avoid gluten at home lately, since I am apparently genetically predisposed to sensitivity and Celiac disease, although I have never exhibited any symptoms. But I eat bread, pizza and pasta when out to certain restaurants (a few times a month).

[Sibiriak]

10 hours ago, Ron Put said:

I thought the soy scare nonsense died a long time ago and only meat industry shills would bring it up now and again on social media....
Soy and Health Update: Evaluation of the Clinical and Epidemiologic Literature

To be consistent, it should be pointed out that the author of the study you cite,  Mark Messina,  works for the soy industry.

Quote

The author is the executive director of the Soy Nutrition Institute, an organization funded by the United Soybean Board and its soy industry members.

Not that that automatically discredits his many papers in support of soy,  but it does suggest that his work is likely  biased to some extent and that one should  be sure to review research and arguments from other sources as well.

Edited October 20, 2019 by Sibiriak

[Ron Put]

10 hours ago, Sibiriak said:

To be consistent, it should be pointed out that the author of the study you cite,  Mark Messina,  works for the soy industry.

...

Hah! I didn't see that ((embarrassed)). Fair point and thanks for pointing it out.

On the other hand, there is really no evidence of any significant adverse effects caused by soy that I am aware of. There are a bunch of studies in the last couple of decades, and while one can argue with the reliability of the soy studies claiming purported health benefits, there is really nothing that I am aware of which would cause me to stop consuming soy (come to think of it, I don't consume all that much of it :)

Here is a WebMD page, which kind of states the same:

https://www.webmd.com/food-recipes/news/20110630/benefits-of-soy-a-mixed-bag#1

"Although evidence was lacking for many of soy's proposed benefits, Utian says that "the good news is that we didn't show it carries any significant risk."

Edited October 20, 2019 by Ron Put