Gains in muscular size and strength are associated with a greater release of anabolic hormones, including testosterone and growth hormone. That’s why many athletes and bodybuilders resort to using anabolic steroids, which are based on testosterone, and growth hormone. Another option is to use food supplements that increase the levels of anabolic hormones in the body, including pro-hormones and several herbal formulas that, some studies show, may have a positive effect on anabolic hormone levels.
Often overlooked, however, is the effect of dietary nutrients on anabolic hormone levels. That was the focus of recent research on the dietary patterns of eight strength-trained and 10 physically active men.1 The first part of the study examined the mens’ levels of total testosterone, free testosterone and growth hormone under resting conditions. In the second part of the study five men from each group trained using heavy resistance. They kept food diaries of everything they ate for four days prior to the training sessions.
The results proved surprising in light of the usual advice on what to eat to gain muscle. Eating either insufficient fat or excess protein led to lower testosterone levels. According to the study, the best types of dietary fat for increasing testosterone are saturated and monounsaturated fats. Polyunsaturated fat, usually considered the healthiest type’and the only fat considered essential’had no effect on anabolic hormone levels.
So what are the optimal levels of protein and fat intake for testosterone release? Research shows that protein intake should be between 1.2 and 1.7 grams per kilogram (2.2 pounds) of bodyweight, while fat intake should never dip below 20 percent of total daily calories and should contain saturated and monounsaturated fat sources.
Since monounsaturated fat, found in olive oil and other sources, is far more healthful than saturated fat, it would be prudent to focus more on that than saturated fat. Saturated-fat intake should never exceed 10 percent of total daily calories.
Even though polyunsaturated fat had no effect on anabolic hormone release, it would be a serious mistake to avoid it. Polyunsaturated fats, such as the omega-3s found in fatty fish, are the only type of fat considered essential in the diet.
As for growth hormone, no particular nutrient pattern had any significant effect. Even so, we know that there’s a direct relationship between calorie intake and GH release: A lack of protein or calories tends to depress growth hormone release. IM
1 Satillinen, J., et al. (2004). Relationship between diet and serum anabolic hormone responses to heavy resistance exercise in men. Int J Sports Med. 25:1-7.