9 Apr 2009 -- Soy & Testosterone
This is a perennial debate with lots of good arguments on both side with the unethical meat industry having a big stake in it. The following is from a study which will soon be published in the journal "Fertility and Sterility."
Quoting Drs:
Jill Hamilton-Reeves, Ph.D., R.D. is an Assistant Professor at the College of St. Catherine and an Adjunct Assistant Professor in the Department of Food and Nutrition Science at the University of Minnesota. She currently teaches at the College of St. Catherine and collaborates on nutrition research projects at the University of Minnesota.
Mark Messina, Ph.D. is the co-owner of Nutrition Matters, Inc., a nutrition consulting company, and is an adjunct associate professor at Loma Linda University. His research focuses on the health effects of soyfoods and soybean components. He is chairperson of The Soy Connection Editorial Board.
Conclusions
CONCLUSION:
The results of this meta-analysis show that neither soyfoods nor isoflavone supplements derived from soy and red clover affect either free or total testosterone levels in men. It should be noted, however, that many of the studies included in the full model of the meta-analysis were of poor quality; for example, many were not placebo-controlled and many were relatively short-term, with the average study duration of about 10 wks. On the other hand, isoflavone exposure was quite high relative to typical Asian and Japanese intake. Overall, the results are very reassuring that soy does not lead to any adverse or feminizing effects such as reducing testosterone concentrations in men. These data also indicate that changes in circulating levels of testosterone are not a mechanism for the proposed role of soy in reducing prostate cancer risk.
Soy and Testosterone Levels
The isoflavones in soybeans – also commonly referred to as phytoestrogens – have been posited to be alternatives to conventional hormone therapy. Not surprisingly therefore, there has been considerable investigation of the effects of soyfoods on the health of menopausal women. By comparison, there has been less research on the effects of soyfoods in men although an exciting field of
study is the potential role of soy in reducing risk of prostate cancer.
The estrogen-like effects of isoflavones have also led to interest in understanding the impact of soyfoods and isoflavone supplements on
testosterone levels in men. Elevated testosterone is a risk factor for prostate cancer. On the other hand, low testosterone levels are associated with a loss of energy, depressed mood, decreased libido, erectile dysfunction, decreased muscle mass and strength, increased fat mass, osteoporosis and possibly, increase risk of coronary heart disease.
Two small studies have reported decreases in testosterone in response to large amounts of soy; however, each study suffered from methodological problems.
9 Apr 2009 -- Soy & Testosterone
This is a perennial debate with lots of good arguments on both side with the unethical meat industry having a big stake in it. The following is from a study which will soon be published in the journal "Fertility and Sterility."
Quoting Drs:
Jill Hamilton-Reeves, Ph.D., R.D. is an Assistant Professor at the College of St. Catherine and an Adjunct Assistant Professor in the Department of Food and Nutrition Science at the University of Minnesota. She currently teaches at the College of St. Catherine and collaborates on nutrition research projects at the University of Minnesota.
Mark Messina, Ph.D. is the co-owner of Nutrition Matters, Inc., a nutrition consulting company, and is an adjunct associate professor at Loma Linda University. His research focuses on the health effects of soyfoods and soybean components. He is chairperson of The Soy Connection Editorial Board.
Conclusions
CONCLUSION:
The results of this meta-analysis show that neither soyfoods nor isoflavone supplements derived from soy and red clover affect either free or total testosterone levels in men. It should be noted, however, that many of the studies included in the full model of the meta-analysis were of poor quality; for example, many were not placebo-controlled and many were relatively short-term, with the average study duration of about 10 wks. On the other hand, isoflavone exposure was quite high relative to typical Asian and Japanese intake. Overall, the results are very reassuring that soy does not lead to any adverse or feminizing effects such as reducing testosterone concentrations in men. These data also indicate that changes in circulating levels of testosterone are not a mechanism for the proposed role of soy in reducing prostate cancer risk.
Eat Tomatoes to Foil Prostate Cancer
NEW YORK (Reuters Health) - Eating tomato sauce a couple of times a week may reduce prostate
cancer risk, according to the results of a study including nearly 48,000 men.
Previous research has yielded conflicting results on whether consumption of tomato products affects
prostate cancer risk, Dr. Edward Giovannucci from Harvard School of Public Health in Boston,
Massachusetts, and colleagues note.
Studies have largely focused on lycopene, an antioxidant abundant in tomatoes. Antioxidants may help
shield against cancer and heart disease by neutralizing harmful molecules known as oxygen free
radicals.
In the current study, published in the March 6th issue of the Journal of the National Cancer Institute
(news - web sites), the research team analyzed data from 47,365 men who participated in the Health
Professionals Follow-up Study. The men completed dietary questionnaires in 1986, and .
From 1986 through , 2,481 participants were diagnosed with prostate cancer.
The reduction in prostate cancer risk was even greater when tomato sauce intake was considered, the
authors note. Men who ate two or more servings of tomato sauce each week were 23% less likely to
develop prostate cancer during the study period than men who ate less than one serving of tomato
sauce each month.
The associations with lycopene and tomato sauce intake persisted after controlling for fruit and
vegetable intake as well as olive oil use, the report indicates.
~~~
Tomatoes: the red colouring pigment, Lycopene, is ruch in various bioactive substances that protect organisms from cell damaging free radicals, strengthen the immune system, and even ward off badteria and fungi.
Tuesday December 18 5:54 PM ET
Tomato Sauce May Benefit Prostate Cells
By Suzanne Rostler
NEW YORK (Reuters Health) - Consuming tomato-based products may reduce DNA damage in the
prostate cells of men with prostate cancer, a new study suggests.
The report found that those patients who consumed one daily pasta dish with tomato sauce for 3
weeks had lower levels of DNA damage in prostate tissues and cells. Pasta eaters also had lower
levels of prostate specific antigen (PSA), a protein in the blood that is measured to assess the risk of
prostate cancer.
The researchers attribute their findings to lycopene, an antioxidant found abundantly in tomato sauce,
and note that earlier studies have found a correlation between a high intake of lycopene and a lower
risk of prostate cancer. Lycopene, they explain, may help to reduce damage caused by free radicals,
naturally occurring byproducts of metabolism which lead to aging and disease. The study included 32
prostate cancer patients ages 60 to 74 who were compared with seven men who did not eat the
additional tomato-sauce based meals.
Cooked tomatoes may lower prostate cancer risk
NEW YORK, Jan 26, (Reuters Health) -- A bowl of tomato soup a day may help keep
prostate cancer at bay, results of a study suggest. Men who eat such tomato-based foods
may have a ``small reduction'' in prostate cancer risk, according to study authors, Dr. Alan
Norrish, of the University of Auckland in New Zealand, and colleagues.
Overall, the men who consumed the highest amount of tomato-based foods such as cooked
tomatoes, tomato soup or puree, tomato juice, ketchup, and tomato-based pasta sauce had
an 18% reduction in prostate cancer. However, the small drop in risk may also have been
due to a statistical fluke, the authors note.
TOMATOES
Thu Jul 15,11:26 PM ET
WASHINGTON (Reuters) - Eating broccoli and tomatoes together may offer better protection against prostate cancer than eating either vegetable alone, cancer researchers reported on Thursday.
They said their study, done in rats, supports the idea that the mixtures of compounds in foods work together to preserve health. It also suggests that supplements alone will not work to prevent cancer, the team at the University of Illinois at Urbana said.
"We decided to look at these foods in combination because we believed it was a way to learn more about real diets eaten by real people," said John Erdman, a professor of food science and nutrition, who led the study.
"Of course, it's important to analyze how specific food components influence our health, but such findings provide only the tools for further study. They should open the debate, not close it down," Erdman told a news conference sponsored by the American Institute for Cancer Research.
Tomatoes are especially hailed as protective against prostate cancer, and scientists believe the lycopene that makes them red may be responsible. But Erdman and colleagues found last year that lycopene supplements did little to prevent cancer in rats.
Broccoli is also believed to help prevent cancer, because it contains compounds called glucosinolates and perhaps other healthful molecules.
The study, which will be published in the December issue of the Journal of Nutrition, shows tomatoes and broccoli may act synergistically, Erdman said.
"Separately, these two foods appear to have enormous cancer-fighting potential. Together, they bring out the best in each other and maximize the cancer-fighting effect," Erdman said.
~~~
Prostate Cancer
The article discusses the relationship between prostate cancer and dairy consumption, indicating that there is a significant connection between the two. The article references multiple studies that have found a greater likelihood of developing prostate cancer in men who consume dairy products in large quantities. To decrease the risk of prostate cancer, the article advises men to limit their consumption of high-fat animal-based foods and instead consume mostly plant-based foods. Additionally, the article points out the link between milk consumption and insulin-like growth factor (IGF-1), which is thought to be a major contributor to the development of prostate cancer.
SOY
Fish, eggs and beans
Hair is primarily made of protein and, therefore, it makes sense to eat a protein-rich diet if you’re trying to maintain your healthy hair. However, eating a steak every day isn’t going to help you. High-fat diets will result in increased testosterone levels, which has been linked to hair loss -- so steaks are not among the foods that prevent hair loss. Stick to leaner proteins such as fish (which has a myriad of health benefits beyond just maintaining your hair), chicken, calf’s liver, brewer’s yeast, low-fat cheese, eggs, almonds, beans, and yogurt. Soy milk and tofu are also smart to add to your diet because they are high in protein and low in bad fats.
~~~
There were no differences in testosterone levels among the four treatments. The researchers concluded, "This investigation shows that 12 week supplementation with soy protein does not decrease serum testosterone or inhibit lean body mass changes in subjects engaged in a resistance exercise program."
~~~
Phytoestrogens (phyto meaning plant) are naturally occurring estrogenic compounds that are found in a variety of foods, herbs, spices. Their chemical structure resembles estrogen. These compounds are generally weak estrogens, in comparison to real estrogen and xenoestrogens, but in a body that is already experiencing too much estrogen, adding more may contribute to the problem.
Some of the strongest phytoestrogen containing substances are soy, the lignans found in flax seed products, red clover, black cohosh, chasteberry, and dong quai. Soy includes soybeans, soy milk, tofu, tempeh, textured vegetable protein, roasted soybeans, soy granules, miso, and edamames.
According to Dr. John Lee M.D., an authority on hormonal imbalances and estrogen dominance, “it is possible that we—men, women, and children—are all suffering a little from estrogen dominance, because there is so much of it in our environment. You would have to virtually live in a bubble to escape the excess estrogens we’re exposed to through pesticides, plastics, industrial waste products, car exhaust, meat, body care products, and indoor toxins.” (pg. 48 Premenopause book).
~~~
Effect of Soymilk Consumption on Serum Estrogen and Androgen Concentrations in Japanese Men1
Chisato Nagata2, Naoyoshi Takatsuka, Hiroyuki Shimizu, Haruo Hayashi, Tomomitsu Akamatsu and Kyouichi Muras
Department of Public Health, Gifu University School of Medicine, Gifu 500-8705 [C. N., N. T., H. S.]; Self-Defense Forces Gifu Hospital, Gifu 504-8701 [H. H., T. A.]; and Gifu Prefectural Gifu Hospital, Gifu 500-8717 [K. M.], Japan
Soy consumption has been associated with a reduced risk of prostate cancer. The mechanism for this association may involve the effect of soy on the endocrine system. We conducted a randomized dietary intervention study to determine the effects of soy consumption on serum levels of steroid hormones in men. Thirty-five men were randomly assigned to either a soymilk-supplemented group or a control group. The men in the soy-supplemented group were asked to consume 400 ml of soymilk daily for 8 weeks. The men in the control group maintained their usual diet. Blood samples were obtained just before the initiation of the dietary period and thereafter every two weeks for 12 weeks.
Changes in hormone concentrations were analyzed and compared between the two groups using the mixed linear regression model against weeks from the start of the dietary period. The mean (SD) soymilk intake estimated from dietary records during the dietary study period was 342.9 (SD, 74.2) ml in the soymilk-supplemented group. There was a significant difference between the two groups in terms of changes in serum estrone concentrations, which tended to decrease in the soy-supplemented group and increase in the control group over time. None of the other hormones measured (estradiol, total and free-testosterone, or sex hormone-binding globulin) showed any statistical difference between the two groups in terms of patterns of change. The results of the study indicate that soymilk consumption may modify circulating estrone concentrations in men.
~~~
Protein supplements made from soy, a known source of phytoestrogens, are commonly used in the community without a clear understanding of the their biological effects in men or women. Prior studies clearly show that pharmaceutical estrogens have profound biological and clinical effects. In contrast, claims about the therapeutic effects of herbal estrogens remain mostly unproven.
---------
Purpose: To determine if a commonly used soy protein supplement exhibits biological activity in vivo and in vitro, we evaluated an over-the-counter soy protein powder supplement using blood from healthy male volunteers and in an estrogen receptor in vitro assay.
Subjects and Methods: We recruited healthy male volunteers 18 years of age or older that were in good health. Treatment consisted of consuming two scoops (56 g) of pure soy protein powder (Puritan's Pride, Oakdale, NY) daily for 28 days. Serum testosterone and luteinizing hormone (LH) levels were collected on days –7, 0, 14, and 28 of therapy, and day 42. A reporter estrogen receptor (ER) assay was used to determine the effect on ER-ß and ER- in vitro.
Results: Twelve subjects were enrolled with a mean age of 32.25 years (range 25 to 47). Serum testosterone decreased 19%(±22%) during the 4-week use of soy protein powder (P = 0.021) and increased within 2 weeks after we discontinued soy protein powder. Serum LH concentrations decreased during the 4-week use of soy protein powder then increased within 2 weeks after we stopped the soy protein powder, but the changes did not reach statistical significance (P = 0.20). Soy protein powder was found to induce agonist activity to ER-ß using a reporter estrogen receptor assay in yeast.
Conclusion: Soy protein powder decreases serum testosterone levels in healthy men and acts as an ER-ß agonist; the significance of this biological effect with respect to cancer prevention needs further study. (Cancer Epidemiol Biomarkers Prev 2007;16(4):829–33)
~~~
Only three intervention studies reported hormonal effects of soy isoflavones in men. These recent studies in men consuming soyfoods or supplements containing 40–70 mg/d of soy isoflavones showed few effects on plasma hormones or semen quality. These data do not support concerns about effects on reproductive hormones and semen quality.
~~~
There’s an excellent book that I read a couple years back titled The Whole Soy Story by Kaayla T. Daniel. It’s an eye-opening read about American’s favorite “health food.” And here is another WAPF article on the soybean, describing the detriments of those processed soy products in the store. The bottom line is: Avoid the bean, unless it’s fermented, and then keep it to a minimum.
Sources:
Soy Dangers Summarized http://www.soyonlineservice.co.nz/03summary.htm
Soy Alert! - Weston A. Price http://www.westonaprice.org/soy/soy_controversy.html
Mothering Magazine - Whole Soy Story: The Dark Side of America’s Favorite Health Food http://www.mothering.com/articles/growing_child/food/soy_story.html
~~~
[in context of prostate]
Isoflavones are found in soybeans and are one of a group of plant chemicals known as phytoestrogens that can balance estrogen in the body. They can reduce estrogen activity when it is high by blocking receptor sites and increase estrogen activity when it is low by acting like a weak estrogen.
~~~
Increased urinary E2 (urinary estradiol) excretion and 2:16 OH-E1 ratio (2-hydroxy estrogens to 16-hydroxyestrone) in men consuming soy protein isolate are consistent with studies in postmenopausal women and suggest that soy consumption may be beneficial in men at high risk of progressing to advanced prostate cancer as a result of effects on endogenous estrogen metabolism.
~~~
Eat Tofu – Arguably the world's most perfect food, eaten by the world's longest lived women. Contains a plant estrogen that makes skin look younger
~~~
This one is by soy food council
Soy and Testosterone Levels
The isoflavones in soybeans – also commonly referred to as phytoestrogens –
have been posited to be alternatives to conventional hormone therapy. Not
surprisingly therefore, there has been considerable investigation of the effects of
soyfoods on the health of menopausal women. By comparison, there has been
less research on the effects of soyfoods in men although an exciting field of
study is the potential role of soy in reducing risk of prostate cancer.
The estrogen-like effects of isoflavones have also led to interest in
understanding the impact of soyfoods and isoflavone supplements on
testosterone levels in men. Elevated testosterone is a risk factor for prostate
cancer. On the other hand, low testosterone levels are associated with a loss
of energy, depressed mood, decreased libido, erectile dysfunction, decreased
muscle mass and strength, increased fat mass, osteoporosis and possibly,
increase risk of coronary heart disease.
Two small studies have reported decreases in testosterone in response to large
amounts of soy; however, each study suffered from methodological problems.
For example, in one, most of the reported decrease resulted from the very large
decrease that occurred in one subject who had abnormally high testosterone
levels at study onset.
To evaluate the effects of soy and isoflavones on testosterone levels,
researchers associated with several different universities conducted a statistical
analysis of all relevant clinical trials. Although the study is not yet published, the
researchers concluded, on the basis of approximately 30 trials, that neither
soyfoods nor isoflavone supplements affect total or free (biologically
available) testosterone levels in healthy men or cancer patients.
Thus, it appears that, if soy does reduce prostate cancer risk, decreasing
testosterone levels is not a possible mechanism. Conversely, these findings also
show that men who eat soy won’t suffer from the consequences of low testosterone as a result.
Looking across multiple studies, vegetarians were found to have a 9% lower risk of death overall, 29% lower risk of death from heart disease, and 18% lower risk of cancer vs. non-vegetarians.
Men with the highest plant-based diet score had a 19% lower risk of fatal prostate cancer vs men with the lowest diet score.
Eating a healthful plant-based diet was linked to a lower risk of being diagnosed with localized prostate cancer.
Some effects of diet differed by age. For example, among men under age 65 at diagnosis, eating a more plant-based diet was linked to a 42% lower risk of advanced prostate cancer.
https://www.pcf.org/c/plant-based-diets-and-prostate-cancer/
In men, being a fish-eater or a vegetarian was associated with a lower risk of prostate cancer (0.80, 0.65–0.99 and 0.69, 0.54–0.89, respectively)
~~~
https://prostatecancerinfolink.net/2009/02/03/celibacy-and-prostate-cancer-risk/
In addition, Michalek et al. identified only 12 deaths from prostate cancer as compared to a projected number of 19.8. This represents a prostate cancer mortality experience that was actually 39 percent lower than that of the general, non-celibate population.
~~~
An 18-year Harvard study of nearly 30,000 health professionals determined that risk of prostate cancer was reduced by 20 percent for men who ejaculated 21 times a month, compared to men who ejaculated four to seven times a month.
A similar Australian study found the risk was reduced by 36 percentTrusted Source when men ejaculated seven times a week.
https://scitechdaily.com/how-intermittent-fasting-extends-life-spans-time-restricted-eating-reshapes-gene-expression-throughout-the-body/
time-restricted eating improved the health of firefighters, who are typically shift workers.
70 percent of mouse genes respond to time-restricted eating
“By changing the timing of food, we were able to change the gene expression not just in the gut or in the liver, but also in thousands of genes in the brain,” says Panda.
“Circadian rhythms are everywhere in every cell,” says Panda. “We found that time-restricted eating synchronized the circadian rhythms to have two major waves: one during fasting, and another just after eating. We suspect this allows the body to coordinate different processes.”
~~~
looking across dies, vegetarians were found to have a 9% lower risk of death overall, 29% lower risk of death from heart disease, and 18% lower risk of cancer vs. non-vegetarians.
Men with the highest plant-based diet score had a 19% lower risk of fatal prostate cancer vs men with the lowest diet score.
Eating a healthful plant-based diet was linked to a lower risk of being diagnosed with localized prostate cancer.
Some effects of diet differed by age. For example, among men under age 65 at diagnosis, eating a more plant-based diet was linked to a 42% lower risk of advanced prostate cancer.
https://www.pcf.org/c/plant-based-diets-and-prostate-cancer/
In men, being a fish-eater or a vegetarian was associated with a lower risk of prostate cancer (0.80, 0.65–0.99 and 0.69, 0.54–0.89, respectively)