Although cutting out egg yolks is sometimes recommended for dieters because they are high in calories, the yolks can be beneficial in a number of ways. One way in which egg yolks can provide benefits for athletes is by enhancing levels of testosterone. Several nutrients in egg yolks may be conducive to promoting increased testosterone levels, but egg yolks aren't recognized as a dietary supplement or a cure for any condition, so your results may vary.
Fat Content
Many people eat egg whites, rather than whole eggs, because the yolks contain all of the fat in eggs. However, this fat can be beneficial if you want to increase your testosterone levels. A study published in the December 1996 edition of "The American Journal of Clinical Nutrition" found that increased fat intake promoted increases in testosterone levels.
Calcium
Egg yolks are rich in the mineral calcium. Calcium is an important nutrient, often found in dairy products, that can help maintain the strength of your bones and teeth. Additionally, a study published in the December 2008 issue of "Biological and Trace Element Research" explains that calcium may help increase testosterone levels.
Vitamin D
Egg yolks are a rich source of vitamin D. This vitamin helps promote proper immune function and regulates calcium levels. Additionally, research from the March 2011 issue of "Hormone and Metabolic Research" indicates that increased vitamin D intake can produce higher testosterone levels.
Aspartic Acid
Because egg yolks are high in protein, they are also rich in amino acids, which are the building blocks of protein. Eggs are particularly rich in aspartic acid, an amino acid which research from the October 2009 edition of "Reproductive Biology and Endocrinology" found could significantly increase testosterone levels in just 12 days.
References
- USDA National Nutrient Database: Egg, Yolk, Raw, Fresh
- "The American Journal of Clinical Nutrition"; Effects of Dietary Fat and Fiber on Plasma and Urine Androgens and Estrogens in Men: A Controlled Feeding Study; J.F. Dorgan et al.; December 1996
- "Biological Trace Element Research"; Testosterone Levels in Athletes at Rest and Exhaustion: Effects of Calcium Supplementation; V. Cinar et al.; December 2008
- National Institutes of Health Office of Dietary Supplements; Dietary Supplement Fact Sheet: Vitamin D; June 2011
- "Hormone and Metabolic Research"; Effect of Vitamin D Supplementation on Testosterone Levels in Men; S. Pilz et al.; March 2011
- "Reproductive Biology and Endocrinology"; The Role and Molecular Mechanism of D-Aspartic Acid in the Release and Synthesis of LH and Testosterone in Human and Rats; October 2009
