Periods of fasting have also been shown to reduce gut permeability leading to blunted postprandial endotoxemia and systemic inflammation, which are typically elevated in obesity 47,48. Testosterone is the major androgenic steroid hormone in adult males and is responsible for maintaining sperm production, libido, and sexual efficacy . Prolactin is a hormone responsible for milk production and mammary gland development . Changes in gonadotropins during fasting have only been assessed in one clinical trial to date (Table 1). Gonadotropins are peptide hormones that regulate ovarian function and are essential for normal growth, sexual development, and reproduction . Interestingly, these improvements in SHBG occurred despite no change in body weight .
In interpreting these findings, it is important to note that very few studies have been conducted in this topic area. Future studies in women should involve perimenopausal and postmenopausal females, since no studies have been performed in these groups of women to date. While these findings offer promise for the use of early TRE in improving certain sex hormone concentrations, further research is needed before solid conclusions can be reached. Improving abnormal microbiomes may lead to better reproductive health outcomes among pre- and postmenopausal women . Studies have shown that alterations in the gut microbiome can significantly affect reproductive hormones . The short time frame of the study (4 weeks) may have also prevented meaningful changes in SHBG from being observed. This finding suggests that total testosterone may have decreased or that testosterone became bound to other carriers such as albumin .
Interestingly, the decreases in the anabolic hormone, testosterone, did not lead to any deleterious body composition changes or compromises in muscular strength. ADF involves a "feast day", where individuals eat ad libitum, alternated with a "fast day", where participants can choose to consume only water or consume ∼25% of energy needs. On the other hand, fasting may be shown to decrease androgens among males, which could negatively affect metabolic health and libido.
For example, it showed that fasting could decrease testosterone levels in women while increasing sex hormone-binding globulin (SHBG) levels in premenopausal females who were overweight. If your testosterone levels and body weight are within a normal range, fasting may not be needed or beneficial. However, intermittent fasting that causes weight loss may support long-term testosterone production in the overweight population. Another study revealed that fasting promotes a reduction in insulin levels, which indirectly benefits testosterone by improving metabolic health. One study found that intermittent fasting increases luteinizing hormone (LH), which directly stimulates testosterone production. In recent years, more men have turned to intermittent fasting as a strategy not just for weight loss, but to enhance hormone production and vitality. However, it is unclear whether the simultaneous reduction in TTV and hormones regulating reproduction during 8 days of water-only fasting could alter testicular function.
The study was conducted according to the guidelines of the Declaration of Helsinki, and approved by Scientific Research Ethics Committee at the Jan Długosz University in Częstochowa (resolution number KB-U/1/2019). Thereby its serum levels may vary essentially in the baseline values 101,102,103. This creates the possibility of a larger amount of bound testosterone and thereby maintaining its bioavailability at a constant physiological level. Thus, other unknown factors affect serum cholesterol levels in addition to dietary cholesterol intake. It should be mentioned here that cholesterol is a precursor of steroid hormones, 98,99. It means, that patients with CKD should be recommended to consume "normal" amounts of moderately mineralized water. In modern societies many people consume too little water which is accompanied by a high intake of salt (Na+).
I was anxious about the fast because I knew prolonged fasting can lower testosterone, but to my relief my testosterone didn’t change. In 2003, David Blaine ate nothing for 44 days fast leaving him dangerously depleted - He suffered from blurred vision, back pain and heart palpitations … but while it was finally time to eat, he was entering the most dangerous part of his fast. On the one hand, fasting may prove to be a valuable tool for treating hyperandrogenism in females with PCOS by improving menstruation, fertility, and quality of life.
When measuring testosterone levels before and after 56 hours of fasting, testosterone levels decreased in the non-obese group (from 8.2 to 6 micrograms per liter), while in the obese group, there was no significant change (4 vs. 3.6 micrograms per liter). On the other hand, a study from 1989 suggests that intermittent fasting temporarily increases testosterone, potentially due to metabolic adaptations and hormonal responses. For young men who were already lean and physically fit, fasting reduced testosterone levels but had no impact on SHBG levels. By understanding the connection between lifestyle factors and testosterone levels, we can see how cultivating healthy habits can optimize hormone balance and support overall health. This article explores whether fasting could potentially increase your testosterone levels. 44 days is an extremely long fast - obviously there has to be a point where you are fasting too much - you need to balance fasting with refeeding and nourishing your body. But the point is, fasting seems to prime the body to be able to increase testosterone production in some people when they eat again.
These hormonal changes contribute to enhanced muscle growth, better energy levels, and overall vitality. Just make sure you hit your protein and calorie targets during your eating window. If you’re unsure whether your sex drive is healthy or not, take a moment to read what is a healthy sex drive for men to understand your natural baseline. And when combined with testosterone-friendly habits, it can transform how you look, feel, and perform—in bed and in life. Most testosterone is produced during sleep and peaks in the early morning. You don’t need a lab test to see signs of testosterone improvement.
Weighing up the data and research it does appear that intermittent fasting can increase testosterone. A diet built around fasting has been shown to provide some amazing health and dietary benefits. Todays modern, processed diets have led us to be a world full of people with slow metabolism, excess belly fat and more prone to certain diseases and health conditions than ever before.

Gender: Female

Social links