Blog Post

Nutrition for Increasing Testosterone

Nutrition for increasing testosterone

Testosterone is a vital hormone for both men and women, although it is commonly associated with male health.

It is crucial to our well-being and plays a role in aspects such as muscle growth, bone density, libido, and overall vitality.

While there are numerous factors that influence testosterone levels, nutrition is one area that can significantly impact its production and maintenance.

Dietary Fats

Dietary Fat

Testosterone is synthesized from cholesterol in the Leydig cells of the testes. Since dietary fats are required to make cholesterol, these act as necessary building blocks for the body to produce testosterone.

Studies comparing diets with 20% and 40% of daily caloric intake originating from fat have consistently demonstrated that adopting a lower fat intake leads to decreased testosterone levels in both males and females.

A 2021 systematic review also showed that testosterone levels were 10-15% lower in those following a low-fat diet (20% of total energy intake) than those following a high-fat diet (40% of total energy intake).

The type of fats may also matter.

One study found that increasing the polyunsaturated to saturated fat ratio whilst keeping total fat intake stable, decreased total testosterone by 15% after 6 weeks.

It’s important to note that this did include a complete shift in dietary intake (going from a mixed diet to lacto-ovo vegetarian), so there may have been other factors influencing this too.

Similarly, another study found that men consuming a diet that had a lower polyunsaturated fat-to-fat ratio had 13% higher testosterone. However, the fibre intake greatly differed between diets.

One even showed a decrease in total testosterone from high polyunsaturated fat intake in older population groups.

This was similar to research done on Japanese men, which showed that intakes of polyunsaturated fat intakes were significantly inversely correlated with total testosterone, whereas saturated and monounsaturated fats were not.

Other studies done in rodents show similar results, however, it’s hard to extrapolate that into humans.

Researchers speculate this may be due to greater rises in cholesterol, higher rates of oxidative stress from omega-6, or changes in the lipid composition of testicular plasma membranes. However, more research is needed to determine the mechanism underlying these findings.

It is important to note that going excessively high in saturated fats can increase levels of LDL cholesterol, which can have a negative impact on heart health.

Having Excess Body Fat

Scale and measuring tape for excess body fat.

Having an excess amount of body fat has been shown to reduce testosterone levels.

There are multiple mechanisms explaining this.

Firstly, adipose tissue contains an enzyme called aromatase, which converts testosterone into oestrogen.

Excess body fat is also associated with higher levels of sex hormone-binding globulin (SHBG). This binds to testosterone in the bloodstream and reduces its bioavailability.

Adipose tissue produces leptin, a hormone involved in regulating appetite and energy balance. High levels of leptin, commonly observed in individuals with excess body fat, can suppress the production of luteinizing hormone (LH) by the pituitary gland. LH stimulates testosterone production in the testes, so reduced LH can lower testosterone production.

However, this is reversible as testosterone has been shown to increase after weight loss occurs.

Body weight loss and impact on testosterone.

A meta-analysis showed that a 9.8% decrease in weight caused by diet led to a 2.9 nmol/L (84 ng/dL) increase in testosterone. Further increases were seen with greater weight loss from bariatric surgeries.

Other studies show that even weight loss of just 5% can have a positive effect on testosterone.

Being Excessively Lean

Being excessively lean with callipers.

On the other hand, being excessively lean also seems to decrease testosterone levels.

When fat mass falls, so does leptin. Similarly to having very high levels of leptin, having low levels of this hormone also reduces testosterone production.

A study that was done on a bodybuilder during preparation for competition found that their body fat decreased from 14.8% to 4.5%. This resulted in more than a 70% reduction in testosterone (9.22 to just 2.27ng/mL).

This has been mimicked in other studies showing that those with under 10% body fat had 32% lower total testosterone than those with an average of 23.2%.

Energy Intake

Knife and fork with empty plate. Low energy from food.

Calorie deficits may also influence testosterone levels.

This is because having low energy availability limits the body’s ability to support normal physiological functions.

To compensate, the body may attempt to conserve energy by downregulating certain processes, including hormone production.

Specifically, this has been shown to downregulate processes that stimulate LH and follicle-stimulating hormone (FSH), both of which are responsible for testosterone synthesis.

Larger caloric deficits in females have been shown to cause a greater drop in testosterone compared with smaller calorie deficits in healthy-weight subjects.

Similarly, 2 out of 3 studies in a recent review showed significant decreases in testosterone where calorie restriction was examined in healthy-weight men.

Vitamin D

Vitamin D

Studies show that as vitamin D levels increase from the lowest to the highest range, testosterone levels also tend to increase, reaching a plateau at the highest quintile.

Supplementation has also been shown to increase testosterone in those with low vitamin D.

This is because vitamin D receptors are found in cells located in the testes where the synthesis of testosterone from cholesterol occurs.

Mice with a deficiency in these receptors exhibit inadequate gonadal function.

Ultimately, to optimize testosterone levels, it would be worth aiming for the upper end of the vitamin D healthy range via a blood test.

Zinc

Dietary zinc.

Research has shown that being deficient in zinc decreases levels of testosterone, while supplementation when deficient increases testosterone.

This is because zinc is an essential mineral and is involved in numerous enzymatic reactions that are necessary for testosterone synthesis.

 It also inhibits the aromatase activity of an enzyme that converts testosterone into oestrogen.

Therefore, ensuring an adequate intake of zinc is important to optimizing testosterone.

Dietary sources of zinc

Since zinc is lost through sweat, athletes are at higher risk for deficiencies.

Supplementation is also an option, however, if zinc intake is sufficient, it will not provide additional benefits.

Magnesium

Magnesium

Increasing magnesium intake in individuals with low levels resulted in a rise in testosterone.

This may be explained through both direct and indirect mechanisms. Magnesium is also a cofactor for several enzymatic reactions that support testosterone synthesis. It is also used to convert vitamin D into its active form.

Additionally, magnesium plays a role in reducing oxidative stress. Since high levels of oxidative stress can impair testicular function and testosterone synthesis, the antioxidant properties of magnesium can help mitigate these effects.

Additionally, magnesium has been shown to inhibit the binding of testosterone to sex hormone-binding globulin (SHBG), thus increasing the amount of free testosterone available in the bloodstream.

Another mechanism that may explain this, is its role in improving sleep, which may help increase testosterone if deficient.

Magnesium rich foods content

Ultimately, to optimize testosterone, aim to consume sufficient amounts of magnesium.

Soy

Soy food

The interaction between soy and oestrogen often gets mentioned as a potential mechanism that may lead to lower levels of testosterone.

Although soy contains phytoestrogens which can mimic the effects of oestrogen, a meta-analysis on the topic has shown no effects of soy intake on testosterone in men.

Supplements

Tongkat Ali

Tongkat Ali

Tongat Ali AKA Longjack or Malaysian Ginseng, is the root of the Tongkat Ali plant.

It contains many bioactive compounds including eurycomanone, which is primarily responsible for the impact seen on testosterone.

One study found that 2 weeks of 600mg/day of Tongkat Ali supplementation (equivalent to 8.7mg eurycomanone), increased total testosterone by 15%.

One proposed mechanism explaining these effects is the inhibition of the aromatase enzyme, preventing the conversion of testosterone to estrogen in the Leydig cells.

Additionally, it has been shown to increase the production of testosterone precursors such as DHEA and androstenedione.

It has also demonstrated other effects such as improvements in erectile function in men.

Rodent studies have identified an increase in sperm production as well, however, no studies have looked at this so far in humans.

Boron

Boron supplement

Boron is a trace mineral found in foods such as apples, nuts, dried fruit, coffee, and avocado and is thought to play a role in the body’s production of hormones.

Subsequently, supplementation has been shown to increase testosterone in both men and women.

It has also been demonstrated to boost magnesium absorption and increase serum levels of vitamin D, which may further raise testosterone in those who are deficient.

Although there appears to be a correlation between boron and testosterone, more research is needed.

Testosterone Boosters

Testosterone booster pills

Most ‘testosterone boosters’ are overhyped and have very little evidence supporting their efficacy.

If there are no deficiencies in the diet, supplementing with test boosters will provide little benefit.

Ashwagandha

Ashwagandha

Ashwagandha is a herb that originated from India and is classified as an adaptogen, helping the body adapt to various stressors.

One study highlighted that it increased testosterone levels in men after 60 days of taking 240mg per day.

Another study demonstrated a 14.7% greater increase in testosterone from men taking ashwagandha for 8 weeks compared to the placebo group.

A systematic review showed a 17% average increase in testosterone across 5 studies.

A potential mechanism explaining these results is its potent effect on reducing stress.

Although it seems promising, the research on ashwagandha and testosterone is fairly limited at this stage.

Summary

Ultimately, most of what is optimal for testosterone when it comes to nutrition is about finding balance.

Addressing nutrient deficiencies like magnesium, vitamin D, and zinc seems to have a very clear impact.

Equally important is avoiding extremes in energy intake and body fat levels.

It may be worth trialing certain supplements, however, given the limited research for many of these, it remains uncertain whether significant outcomes can be expected at this stage.

By Josh Wernham

Josh is a Dietitian based in Brisbane who's passion for nutrition stemmed from an interest in optimising sports performance and body composition. He has a lot of experience in bodybuilding style training and also has a background in team sports, strength and endurance events. As he has grown in the field, this enthusiasm has extended beyond just sports and continuously immerses himself in the latest research to support those with general health conditions. He strives to help a range of individuals, from athletes to anyone seeking to improve the quality of their life.