Plant Based Diet and Testosterone Levels


Hereś an interesting study of how plant based diets affect testosterone levels. The epithet "soy boy" is used not just to describe men who consume soybean products, but also men who avoid meat. So how does a vegetarian or semi-vegetarian ("plant based") diet affect testosterone levels? Not at all, apart from any effect on BMI, it turns out. The abstract says:
"Data on demographics, diet, and testosterone levels was acquired from the NHANES database. Using the food frequency questionnaire, an overall plant-based diet index (PDI) and a healthful plant-based diet index (hPDI) was developed. A higher score on PDI and hPDI indicates higher consumption of plant foods.
"A total of 191 participants were included, average age was 45 (30-60) years and average total testosterone level was 546.7 ± 254.7 ng/dL. On multiple linear regression analysis, BMI and age significantly contribute to testosterone levels (p < 0.05); however, neither of the diet indexes significantly predicted serum testosterone levels (PDI: p = 0.446; and hPDI: p = 0.056).
"In a well characterized national database, the plant-based diet index is unable to predict testosterone levels. Plant-based food content in diet is not associated with serum testosterone levels."


im not vegan but find the whole soy boy thing hilarious seeing as its ment to be about their being high amounts of estrogen in soy yet the highest estrogen is in dairy and milk


Ok, but what the conclusion? Are you vegan? Cause it is horible to eat just carbs and soy dont you think?
No, I'm not a vegan. The point is, though, that both a vegan diet and a diet with meat can be healthy if they follow the general rules of a healthy diet and unhealthy if they do not. These rules are:
  • Eat unprocessed instead of processed foods
  • Eat whole instead of refined foods
  • Avoid fried foods
  • Avoid sugar
  • Avoid red meat
If you are wondering where protein comes from in a vegan diet, it comes from the combination of grains and legumes. This is a pattern you see in many cultures: corn and beans in Latin America, oat or wheat and peas in Europe, rice and soy in East Asia.


Active Member
The problem with this data is that it is highly unlikely to be applicable to highly active people. If you look at the way the way someone like Mike Mahler eats, he is quite candid about using massive amounts of vegan protein powders.


I don't know Mike Mahler, but fitness coaches sometimes have exaggerated ideas of how much protein one needs. When I started TRT I hired a personal trainer and I asked him how much protein I should eat. He said 1.3 to 1.5 grams / kg of body weight, which for me works out to be 120 grams. He had a degree in exercise physiology and was working on a masters in nutrition, so I think he knew what he was saying. That amount of protein has worked well for me and I believe you can achieve it on a variety of diets, including a healthy vegan diet, without supplementation, or with only a modest amount of supplementation.
I don't believe you should let your fitness goals determine your diet. I think older men should eat a diet that reduces the risk of erectile dysfunction, diabetes, heart disease, and cancer and the amount of protein in the diet is not a factor for this.
No, I'm not a vegan. The point is, though, that both a vegan diet and a diet with meat can be healthy if they follow the general rules of a healthy diet and unhealthy if they do not. These rules are:
IMVHO, and having tried just about every diet that has ever existed over the last 10 years, the problem is that there are very few rules to follow for good nutrition (good news), but very few food scientists/nutritionists agree on what they are. Pre-1977 (1983 in UK), the general advice was to moderate carbohydrate. Post those dates, the advice was changed to advocate an increase in carbohydrates. No one specified what carbs, and Prof John Yudkin even wrote a book to advise of the dangers of simple carbohydrates, which was ignored resoundly by "experts" and governments around the world. The human body is very adept at ignoring (triaging) short-term micro-nutrient shortages, but great damage can occur down the road as we begin to experience atherosclerosis osteoporosis etc. I find that we tend to concentrate on macro-nutrients, which largely determine body composition, to the detriment of our longevity. RDAs, for example, can be considered as minimum requirements, but are treated as goals by most. Many essential minerals have no RDA number given, as there is not even a solid grasp of their health and well-being effects. Iodine and Boron, for example, do not appear in NCCDB analyses of our foods. But what about things like Strontium, Arsenic, Chromium?

Getting back to the Soy theme, some sources argue, rightly or wrongly, that there are reasons to avoid it all together. Having tried to formulate a healthy vegetarian/vegan diet, I'm afraid that it's just very much simpler to obtain both macro and micro nutrients using some animal products.

At the end of the day, nutrition plans, especially in seniors, should be tailored towards the individual, and adapted over time as one gauges their own body's reactions. "Let food be your medicine", hardly a novel concept. Namaste.