Fasting has become an increasingly popular health trend, gaining attention for its potential to promote weight loss, improve metabolic health, and enhance longevity. While most people associate fasting with reduced calorie intake and detoxification, there is growing interest in its effect on hormone regulation, particularly testosterone.
Testosterone’s Effects
Additionally, there is growing interest in its effect on hormone regulation, especially testosterone. Testosterone is vital for:
- Muscle growth
- Mood regulation
- Erectile Function in males
- Energy levels
- Libido
However, testosterone levels naturally decline with age, leading to symptoms like fatigue, decreased muscle mass, and reduced sex drive.
Research has shown that both testosterone and sperm counts have significantly declined over the past few decades, according to an article we published recently. This drop can result in symptoms like fatigue, decreased muscle mass, and reduced sex drive. For this reason, many are exploring ways to boost testosterone levels naturally. One of the proposed methods is fasting, but what does science say?
Types of Fasting
Fasting isn’t a one size fits all approach. Different methods include:
1. Intermittent Fasting (IF): This involves cycling between periods of eating and fasting, such as the popular 16:8 method, where you fast for 16 hours and eat during an 8 hour window.
2. Extended Fasting: This type of fasting lasts longer than 24 hours.
3. Alternate Day Fasting: It involves fasting every other day.
Experts opinion
Dr Mark Holthouse, MD, IFMCP, is board certified from the Loma Linda University School of Medicine. He says,
“It is the intermittent fasting, time restricted eating that is amazing. The question to be answered is, is it other things that we know time restricted eating is inducing at a mitochondrial level that’s causing this? Or is it fat weight loss? Or is it something else? We don’t know where and all of the mechanisms yet, but these are the practices that we can be putting in practice in our clinics every day right now that are free, essentially free to these folks, they don’t have to buy a cuisine that has these kinds of impact.”
He further says,
“The intermittent fasting pace became so much more than just a body composition issue where we’re preferentially losing subcutaneous and intra abdominal fat, which we know is directly related to improving T. But then you throw in this added information that’s coming out regarding uncoupling and how intermittent fasting, time restricted eating is a signal in our cells to do this. It’s pretty exciting.”
Fasting and Testosterone: The Science
Understanding the body composition
Body composition is a significant factor in testosterone levels. Men with higher body fat tend to have lower testosterone due to the presence of aromatase in fat cells. Testosterone is metabolized by two hormones, either by 5 alpha reductase to dihydrotestosterone, which is a more potent form of testosterone and our body needs only tiny amounts of it. Or via aromatase converting it to estrogen, which can lower testosterone levels. By reducing fats, fasting could help to naturally increase testosterone levels.
Role of sleep and stress
Modern lifestyle has brought risks which can lower the testosterone levels. Sleep time of 5 hours and less has been linked to a 10-15% drop in testosterone levels. This significant drop did not take longer than a week. Similarly stress and insulin resistance syndrome has negative effects on testosterone.
Evidence
Understanding the concept of body composition and its effects on our health is of prime significance. I discuss with my patients that when you want to build muscles then your focus should be on exercise. While losing weight is done primarily with time restricted eating and fasting rather than exercise. Intermittent fasting and time restricted eating are amazing. Dr. Valter Longo in the University of Southern San Francisco has worked a lot in this domain. Although the exact mechanisms are being researched on, we now know its direct association with body composition change.
Reducing visceral abdominal fats has shown an increase in T levels. Mingquin Su and his team analyzed data from 1551 participants and concluded that, Men with higher VAI (Visceral Adiposity Index) displayed lower testosterone levels and higher risk of testosterone deficiency, especially in aged men and obese men. That’s dramatic!
Percent body fat was negatively correlated with Testosterone levels in male
Benefits of Fasting for Testosterone
Insulin Sensitivity: Intermittent fasting improves insulin sensitivity by lowering blood sugar levels and reducing insulin resistance. Since insulin resistance is associated with lower testosterone levels, improving insulin sensitivity through fasting may indirectly boost testosterone production.
Ghrelin and Leptin: Fasting affects hunger hormones like ghrelin (which stimulates hunger) and leptin (which suppresses hunger). Some studies suggest that ghrelin may enhance testosterone production by stimulating the release of LH. On the other hand, chronic fasting can lower leptin levels, which might reduce energy stores and potentially negatively affect testosterone production.
Cortisol Levels: One of the potential drawbacks of extended fasting is an increase in cortisol, the body’s primary stress hormone. Elevated cortisol levels can suppress testosterone production, as the body’s focus shifts from reproductive processes to stress response and energy conservation.
Potential Drawbacks of Fasting on Testosterone
While there are potential benefits of fasting on testosterone, there are also risks and limitations:
- Nutrient Deficiency: Prolonged or extreme fasting without proper nutrient intake can lead to deficiencies in vitamins and minerals that are critical for hormone production. Zinc, vitamin D, and healthy fats are particularly important for testosterone synthesis.
- Individual Variability: The response to fasting can vary widely from person to person. Genetics, age, baseline testosterone levels, and overall health all play a role in how someone’s testosterone levels will respond to fasting.
Conclusion: Does Fasting Increase Testosterone?
Fasting may indeed increase testosterone levels, but the relationship is complex and influenced by multiple factors such as the type of fasting, duration, body fat levels, and overall health. Intermittent fasting appears to show the most promise in boosting testosterone, especially when combined with a protein rich diet during the refeeding period. However, extended fasting could lead to elevated cortisol levels, which may suppress testosterone production. We recommend you explore our articles on Ashwagandha and Vig RX to learn about natural supplements that may help you improve your hormonal profile and raise testosterone levels.
