Bfg1, most of the time you and I see eye to eye on most things. But in this case when you say there is no scientific evidence that suggests a low fat diet is detrimental to hormone production I have to tell you that you are wrong on this bro.
According to a study published in the Journal of Clinical Endocrinology and Metabolism, thirty-nine healthy men were studied while they were consuming a high-fat/low-fiber diet and after an eight-week modulation switched to an isocaloric low-fat/high-fiber diet. After diet modulation, blood testosterone concentration fell, accompanied by small decreases in free (biologically active) testosterone.
Cite Wang C et al. Low-fat high-fiber diet decreased serum and urine androgens in men. J Clin Endocrinol Metab, 2005;90:3550-3559.
Also there was a study at Duke that published in the journal Urology. Twenty five men were on the low-fat, flaxseed-supplemented diet for an average of 34 days. Researchers reported good compliance with the diet and said it was tolerated well. At the end of the study, the researchers observed that the men on the diet had significant decreases in cholesterol, and both total and free testosterone.
Research shows that reducing fat intake from around forty percent to 20-25 percent of calories decreases testosterone output. Low fat diets also increase levels of sex hormone-binding globulin (SHBG), a protein which binds to testosterone, thus reducing the amount of bioavailable, or 'free', testosterone in the body. It is free testosterone that is responsible for this hormone's favorable effects on growth, repair, sexual capacity and immune function.
79. Hamalainen EK, et al. Decrease of serum total and free testosterone during a low-fat high-fibre diet. J Steroid Biochem. Mar 1983; 18 (3): 369-370.
80. Reed MJ, et al. Dietary lipids: an additional regulator of plasma levels of sex hormone binding globulin. J. Clin. Endocrinol. Metab, 1987; 64: 1083-1085.
81. Dorgan JF, et al. Effects of dietary fat and fiber on plasma and urine androgens and estrogens in men: a controlled feeding study. Am J Clin Nutr. Dec 1996; 64 (6): 850-855.
Again, not just any old fat will suffice when it comes to optimizing testosterone levels. A study with weight-training men showed higher saturated fat and monounsaturated fat consumption to be positively associated with testosterone levels. In contrast, higher dietary levels of so-called "heart-healthy" polyunsaturated fats relative to saturated fats were associated with lower testosterone levels.
Volek JS, et al. Testosterone and cortisol in relationship to dietary nutrients and resistance exercise. Journal of Applied Physiology, Jan 1997; 82 (1): 49-54.
Hopefully these six or seven studies are enough to prove there is in fact scientific evidence linking low fat diets to decreased hormone production, if not I can find more for you. Its a well documented scientific fact bro. Just a heads for you.
