Are there foods that block testosterone? What the science says

October 13, 2025 •

4 min read

According to one source, the average 40-year-old man today has roughly 30% less testosterone than a man of the same age in 1987. This dramatic shift has fueled speculation and concern, prompting many to ask: Are there foods that block testosterone? While the idea of a single food item having a drastic blocking effect is largely a myth, certain dietary patterns and specific foods can indirectly influence hormone levels, metabolic health, and inflammation.

Quick Summary

This article explores how diet influences testosterone, examining the evidence for specific foods like processed options, alcohol, soy, flaxseed, and mint. It clarifies which foods may negatively affect hormone levels and emphasizes the importance of overall metabolic health over obsessing about individual ingredients.

Key Points

Overall Diet Matters Most: No single food can definitively 'block' testosterone; instead, overall dietary patterns like the Western diet, rich in processed foods, are linked to lower levels.
Processed Foods are a Key Culprit: High intake of refined sugars and trans fats from processed foods contributes to inflammation, weight gain, and insulin resistance, all of which negatively impact testosterone.
Soy Myths are Debunked: Despite common misconceptions, multiple meta-analyses confirm that moderate consumption of soy products does not affect testosterone or estrogen levels in men.
Excessive Alcohol is Harmful: While a single drink may not harm levels, chronic or heavy alcohol consumption can directly damage the testes and interfere with hormone regulation via the liver.
Herbs and Seeds Have Nuances: Ingredients like licorice root and spearmint have shown some testosterone-lowering effects in specific high-dosage studies or animal/female research, but the impact of moderate intake is not well-established in healthy men.
Lifestyle Changes are Paramount: For optimal testosterone, focus on maintaining a healthy weight, exercising regularly, managing stress, getting sufficient sleep, and eating a whole-foods diet.

The relationship between diet and testosterone

Testosterone is a vital sex hormone that affects muscle mass, bone density, and libido in both men and women. While factors like age, genetics, and lifestyle play significant roles in regulating testosterone, diet can also be a key influencing factor. The primary mechanisms through which diet impacts hormone health involve metabolic function, inflammation, and weight management. A healthy, balanced diet supports the body's natural hormone production, while an imbalanced diet high in processed items can disrupt it over time.

Highly processed foods and trans fats

Diets high in refined carbohydrates, added sugars, and trans fats are strongly linked to poor metabolic health, which can, in turn, negatively impact testosterone levels. Processed foods, such as baked goods, sugary snacks, and fried items, promote insulin spikes and contribute to weight gain. This can lead to insulin resistance and obesity, with excess body fat potentially increasing the conversion of testosterone to estrogen via the aromatase enzyme. Additionally, trans fats and excessive sugar can promote chronic inflammation, which may disrupt hormone production. A 2017 study found that young, healthy men with higher trans fat intake had significantly lower total testosterone levels.

The impact of alcohol

The effect of alcohol on testosterone depends heavily on the amount and frequency of consumption. Chronic or heavy drinking is consistently shown to have a suppressive effect on testosterone production. Excessive, long-term alcohol use can damage the Leydig cells in the testes responsible for testosterone production and affect the hormonal signaling system (HPG axis) that regulates it. The liver, crucial for hormone metabolism, can also be compromised by large amounts of alcohol, impacting testosterone regulation.

Soy and phytoestrogens: The real story

The idea that soy products significantly lower testosterone due to phytoestrogens is a persistent myth. Phytoestrogens are plant compounds that can mimic estrogen. However, comprehensive human studies and meta-analyses, including a 2021 review, have largely shown that neither soy protein nor isoflavone intake affects testosterone levels in men. Concerns are mainly based on older animal research or rare instances of extremely high intake. Moderate consumption of soy products is generally not a concern for testosterone levels.

Licorice root and mint

Some ingredients have been studied for their potential hormonal effects.

Licorice Root: Several studies suggest that consuming licorice root may reduce testosterone levels. One study showed a 26% decrease in testosterone in men consuming 7 grams of licorice root daily for a week, linked to glycyrrhizic acid inhibiting enzymes involved in testosterone synthesis. This effect is generally associated with high doses of the root, not small amounts found in candies.
Mint (Spearmint and Peppermint): Research, mainly in animals and women with PCOS, suggests that spearmint and peppermint may reduce testosterone. However, strong evidence of a significant effect in human males is currently limited.

Flaxseed and certain nuts

Flaxseed and some nuts contain compounds that may interact with testosterone.

Flaxseed (Lignans): Flaxseed contains lignans, phytoestrogens that can bind to testosterone, potentially leading to its excretion. A small study in men with prostate cancer showed a significant testosterone reduction with flaxseed combined with a low-fat diet. The effects of moderate consumption in healthy men are less clear.
Certain Nuts: Some studies, primarily in women with PCOS, indicate that almonds and walnuts may increase SHBG. SHBG binds to testosterone, reducing free testosterone. However, the impact in healthy men consuming a balanced diet is likely minimal.

Comparative dietary impact on testosterone

Focusing on broader dietary patterns is more effective than individual foods. The table below compares the general effects of a typical Western diet with a whole-foods approach.


Feature	Western-Style Diet	Whole-Foods Diet
Core Components	High in processed foods, refined sugars, trans fats, excessive alcohol.	Rich in lean protein, healthy fats (olive oil, avocados), whole grains, fruits, and vegetables.
Impact on Weight	Often leads to weight gain, particularly visceral fat, which can increase the conversion of testosterone to estrogen.	Supports healthy weight management, which is crucial for optimal hormone balance.
Inflammation	Promotes chronic inflammation throughout the body, which disrupts hormonal pathways.	Contains anti-inflammatory nutrients and fiber, supporting overall metabolic health.
Hormone Regulation	Can negatively affect the endocrine system, impairing the body's ability to regulate testosterone.	Provides essential nutrients (Zinc, Magnesium, Vitamin D) required for testosterone production and function.
Energy Levels	Associated with energy crashes due to insulin spikes, impacting overall vitality.	Promotes stable energy levels and overall well-being.

Conclusion

While the idea that specific foods can completely block testosterone is an oversimplification, overall dietary patterns and lifestyle choices are significant factors in hormonal balance. Diets high in processed foods, refined sugars, and excessive alcohol are linked to a decline in testosterone. Although some ingredients like licorice root and potentially high amounts of flaxseed have shown effects in specific studies, moderate consumption in healthy individuals is likely to have a minimal impact. To support healthy testosterone levels, prioritize a whole-foods-based diet rich in lean proteins, healthy fats, fruits, and vegetables, while limiting processed items and heavy alcohol use. Consulting a healthcare professional is recommended for personalized advice on hormone health.

Frequently Asked Questions

No, this is a common myth. Extensive and updated meta-analyses of clinical studies have found no significant effect of soy protein or isoflavone intake on testosterone levels in men. The concern is based on older animal studies or isolated case reports involving extremely high intake.

Chronic and heavy alcohol consumption significantly lowers testosterone levels by damaging the testosterone-producing Leydig cells in the testes, disrupting hormonal signals from the brain, and impairing the liver's ability to regulate hormones.

Yes, diets high in processed foods and trans fats are associated with lower testosterone. These foods can cause weight gain and inflammation, which interfere with the body's hormonal balance and increase the conversion of testosterone into estrogen.

Some studies have shown that high daily consumption of licorice root can temporarily lower testosterone levels, possibly by inhibiting enzymes involved in testosterone synthesis. However, this typically requires a high dosage of licorice root extract, not moderate consumption.

Moderate consumption of flaxseed is unlikely to cause problems for most healthy men. Flaxseed contains lignans that can bind to testosterone, but larger-scale studies are needed to determine its effects on testosterone levels in the general population.

Maintaining a healthy weight is critical for hormone health. Excess body fat, particularly around the stomach, can increase the production of aromatase, an enzyme that converts testosterone into estrogen, leading to lower overall testosterone levels.

It is much more effective to focus on your overall dietary pattern and lifestyle. A balanced diet of whole foods, regular exercise, and healthy weight management has a more significant and positive impact on hormone health than avoiding any single food.

Some concerns exist that hormones in dairy products could interfere with testosterone, especially in processed varieties. However, evidence is mixed, and the overall effect of moderate dairy consumption in healthy individuals is not clearly proven to lower testosterone.