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Dylan de Castro wrote on Livestrong in the article Meat Diet for Testosterone:
Eating meat, which is high in protein, helps build muscle and stimulates the secretion of the hormone glucagon, both of which contribute to raising testosterone levels. ...
Is this claim true, and does eating meat help a person increase their testosterone levels?
There have been a few studies conducted on this. The summary is that meat protein contributes more to Total Testosterone than a vegetarian diet.
This link quotes from a book by Lou Schuler - "The Testosterone Advantage Plan" Rodale: USA, 2002.
1985 study found when it looked at a large cross-section of omnivores and vegetarians ... The meat-eaters actually had 36 percent more T than the guys who stuck to rabbit food
A 1989 study found pretty much the same thing: The meat-eaters ate more fat, more cholesterol, more saturated fat, and less fiber than the vegetarians and had 31 percent more testosterone (Schuler, p.86).
A Dutch study published in 1992 looked at changes in T levels on these two diets. A group of young male endurance athletes ate and trained on each diet for 6 weeks. (Half started on the meat-rich diet, half on the vegetarian diet; then they switched.) Total testosterone declined 35 percent when the athletes used the vegetarian diet (Schuler, p.76).
From the same link
Men's Health magazine declared, "Perhaps the ideal diet to drop your testosterone is high fiber and vegetarian-and the ideal way to raise it is the red-meat approach" (Jim Thorton, p.154). " Maximum Testosterone." Men's Health. April, 2005, pp. 146-155,182
An abstract of the 1992 Dutch study is available here
Sample size of 8 male endurance athletes, in summary the Total Testosterone is less on a Vegetarian diet compared to Meat diet, but Free Testosterone does not differ significantly.
Serum sex hormones and endurance performance after a lacto-ovo vegetarian and a mixed diet.
Raben A, Kiens B, Richter EA, Rasmussen LB, Svenstrup B, Micic S, Bennett P. SourceAugust Krogh Institute, University of Copenhagen, Denmark.
The V diet resulted in a lower total T level (13.7, 9.8-32.4 nmol.l-1) (median and range) compared with the M diet (17.4, 11.8-33.5 nmol.l-1). During exercise after 6 wk on the diets total T was also significantly lower on the V than on the M diet
Given that most of the advice on this concentrates on eating red meat, your mileage may vary with other meats and fish protein.
What about study in more recent years? This study published in the year 2000 says that the vegans have 13% higher testosterone concentration than meat eaters and 8% more than vegetarians.
Hormones and diet: low insulin-like growth factor-I but normal bioavailable androgens in vegan men
Summary Mean serum insulin-like growth factor-I was 9% lower in 233 vegan men than in 226 meat-eaters and 237 vegetarians (P = 0.002). Vegans had higher testosterone levels than vegetarians and meat-eaters, but this was offset by higher sex hormone binding globulin, and there were no differences between diet groups in free testosterone, androstanediol glucuronide or luteinizing hormone.
It also says:
SHBG was significantly higher in the vegans than in the meateaters, leading to a corresponding increase in T in order to maintain constant levels of FT, a pattern which has been found in previous smaller observational studies (Key et al, 1990; Pusateri et al, 1990). The differences in SHBG concentrations between dietary groups were reduced but not eliminated by adjusting for differences in BMI, suggesting that nutritional factors specific to a vegan diet may be important determinants of circulating SHBG levels, over and above their effect on BMI.
(where SHBG and T are defined earlier as "sex hormone binding globulin" and "testosterone")
It concludes:
The results did not support the hypothesis that meat-eaters have higher levels of bioavailable androgens than non meat-eaters. No differences in hormone levels were found between meat-eaters and lacto-ovo-vegetarians, suggesting that vegetarian diets may not alter prostate cancer risk, but the relatively low IGF-I levels in vegans might reduce their risk of prostate cancer. Prospective data have shown that vegetarians do not have significantly lower prostate cancer mortality rates than comparable non-vegetarians (Key et al, 1999), but these subjects were predominantly lactoovo-vegetarians and there are, as yet, no data on prostate cancer rates among vegans.
