Your Eating Habits and Your Testosterone Levels—Beware of Extreme Diet Plans
We’ve discussed in past blog posts how chronic consumption of sugary foods and beverages can damage testosterone production, particularly in young men. Therefore, it might be easy to draw the conclusion based on that evidence alone that a low carbohydrate diet—may be one of those fad diet plans that call for heavy consumption of foods high in protein—would be the way to maintain, restore, or otherwise increase testosterone naturally.
We advise caution before going to extremes.
Study the Research Before Making Decisions
Research into how dramatically increasing or restricting carbs and protein affects your testosterone levels is conflicting, which should immediately alert you to be careful.
First, in dealing with sugar and carbohydrates, some oft-cited studies found that low-carb diets boost testosterone, but others show that they reduce testosterone.
A meta analysis of 27 existing studies was published by Whittaker and Harris in 2022, and no substantial evidence was found that (besides avoiding extreme and habitual consumption of sugar) restricting carbohydrate intake had little effect on testosterone levels, but low-carb diets exacerbated cortisol levels both resting and post-exercise after about 3 weeks.
Cortisol is a glucocorticoid hormone that your adrenal glands produce and release. (Glucocorticoid hormones) suppress inflammation in all of your bodily tissues and control metabolism in your muscles, fat, liver and bones. Glucocorticoids also affect sleep-wake cycles.
Cortisol is widely known as the “stress hormone.” However, it has many important effects and functions throughout your body aside from regulating your body’s stress response.
During times of stress, your body can release cortisol after releasing its “fight or flight” hormones, such as adrenaline, so you continue to stay on high alert. In addition, cortisol triggers the release of glucose (sugar) from your liver for fast energy during times of stress.
In short spurts, cortisol can boost your immunity by limiting inflammation. However, if you have consistently high levels of cortisol, your body can get used to having too much cortisol in your blood, which can lead to inflammation and a weakened immune system.
Having chronically high cortisol levels can lead to persistent high blood sugar (hyperglycemia). This can cause Type 2 diabetes.
What about protein? More protein could be assumed to boost testosterone, couldn’t it?
No, that’s not actually what the research concluded. The analysis compiled data showing that moderate-protein, low-carb diets had no consistent effect on resting total testosterone at all.
However, high-protein, low-carb diets greatly decreased resting and post-exercise total testosterone levels.
You read that correctly. Eating too much protein brings your testosterone levels down!
What the Researchers Had to Say
In an interview with MedicalResearch.com, Whittaker, a professional nutritionist, commented:
We found that whilst low carbohydrate diets had no effect on testosterone, high protein diets caused a large decrease in testosterone (approximately 37%). This is very significant, as such a large decrease would give the average man medically low testosterone (hypogonadism). We also found on low-carbohydrates diets increased the stress hormone cortisol, particularly after exercise. Cortisol is known to suppress the immune system, so this effect could be detrimental.
In further comments, he offers stern warning to those who believe the recent fad diets that claim the more protein the better:
Very high protein diets have been shown to have many adverse effects, and our study adds low testosterone to this list. However, the detrimental effects are generally only seen at protein intakes above 35%. The average person eats 15-20% protein, so they have nothing to worry about. People most at risk of excessive protein intakes are bodybuilders, weight lifters, and those on extreme weight loss diets. These people should limit protein to no more than 25% of their daily calories. The finding that low-carbohydrate diets increase cortisol, suggests they suppress the immune system, particularly after exercise. So for athletes and others who exercise a lot, they may need to reconsider using low-carbohydrates diets, particularly if they frequently have colds, flus, and other viral infections.
Low Testosterone and My Eating Habits: What Does This Mean for Me?
Extreme diets or the latest fads should always be looked at with skepticism, and we highly recommend caution.
We’d never discourage you from making positive or medically recommended changes to what you eat or making good-sense increases to your level of exercise, but if you’re looking to drop a lot of weight, put on serious muscle mass, or if you are worried about chronic low testosterone, it is unlikely that dietary choices or healthier habits are going to return your hormone levels to a “normal” or “optimum” range.
Each individual is different, and a conversation with your healthcare provider is recommended before making any major decisions.
Testosterone Replacement Therapy (TRT) is the most effective treatment for low testosterone. For answers to the most common questions regarding the benefits of TRT without the marketing spin that surrounds diet, exercise, and supplements, we recommend reading our comprehensive guide.