These studies clearly indicate the negative effect that low energy availability has on the hypothalamic-pituitary-gonadal axis. Initial investigations reported that a low energy availability (i.e., 13 kcal·kg FFM·day−1) significantly altered LH pulse frequency and amplitude . For example, an athlete training at a high intensity or prolonged duration, while attempting to lose fat mass by reducing caloric intake, may cause a low energy availability. Energy availability is defined as the difference between energy intake and energy expenditure, relative to an individual’s fat-free mass (FFM) . Similarly, Clemesha and colleagues reported that only ~25% of the 50 products they tested claiming to be testosterone boosters had scientific data to support their claims. Balasubramanian and colleagues recently examined the efficacy of the five top-ranked products and reported that the number of human studies conducted provided no definitive evidence for the efficacy of these products. Competitive athletes focusing on enhancing their athletic performance often strive to improve their body composition by increasing lean body mass and decreasing fat mass 65,66,67. There appears to be an abundance of testosterone boosters that are marketed to the consumer. The best dietary sources of PS are organ meats such as brain, liver, heart, and kidney. PS is a phospholipid found in the cell membrane of a variety of tissues, including the brain, lungs, heart, liver, and skeletal muscle. Phosphatidylserine (PS) has also been proposed to enhance the anabolic response to exercise. Others have examined the capability of the element boron on its testosterone-boosting capability 55,56,57. Neves and colleagues identified several flavonoids as equal or better aromatase inhibitors in comparison to the anti-aromatase drug aminoglutethimide, including flavones, flavanones, resveratrol, and oleuropein. LH then stimulates the Leydig cells within the testes to synthesize testosterone. Gonadotropin-releasing hormone (GnRH), released from the hypothalamus, stimulates the release of luteinizing hormone (LH) from the anterior pituitary gland into the circulation. A small amount is transported unbound, referred to as free testosterone (FT) . Once synthesized, testosterone is secreted into the bloodstream and delivered to target tissues . In women, testosterone is produced in much smaller amounts, primarily from the adrenal glands and the ovaries 2,6. Structurally, testosterone has a characteristic four ring C18 steroid structure and is synthesized from cholesterol through an enzymatic multistep process primarily within the Leydig cells (~95%), which are located in the interstitium of the testes. They are important hormones for various biological processes and are vital for the development and maintenance of secondary male characteristics. The impact of protein supplements like whey on testosterone isn’t as clear-cut as some people think, and that’s where it gets tricky. What’s more, testosterone levels fluctuate throughout the day. When discussing protein intake, another common question is how much protein your body can actually digest in one sitting. Now, let’s get something straight—whey protein isn’t some magic potion. However, scientific research has shown that whey protein does not have a significant impact on hormonal balance in healthy individuals. However, the truth is that whey protein is a valuable tool for muscle building and recovery. Alternatively, testosterone supplements may be prescribed by healthcare professionals to individuals with clinically low testosterone levels.
