Fertility Foods: How Metabolic Health and Nutrition Influence Reproductive Health

Fertility depends on the interaction of hormones, ovarian or testicular function, gamete quality, energy availability, nutrient status and metabolic health. Nutrition can influence several of these pathways, but no single food can override an underlying endocrine or metabolic disorder.

One of the clearest examples is Polyendocrine Metabolic Ovarian Syndrome (PMOS), a common reproductive and metabolic disorder associated with hyperandrogenism, ovulatory dysfunction and, frequently, insulin resistance.

This is where the relationship between fertility and metabolic health becomes particularly important.

Insulin and reproductive hormones are connected

Insulin is best known for regulating blood glucose, but it also interacts with reproductive physiology.

In insulin-resistant states, the body may compensate by producing more insulin. In PMOS, hyperinsulinaemia can contribute to increased ovarian androgen production and can reduce hepatic production of sex hormone-binding globulin (SHBG). The result can be a greater amount of biologically active androgen and disruption of normal follicular development and ovulation.

This does not mean insulin resistance causes every case of infertility, nor does every woman with PMOS have clinically significant insulin resistance. However, insulin resistance is an important pathophysiological feature of PMOS and a major reason metabolic health is part of its management. The 2023 International Evidence-based Guideline for PMOS recommends lifestyle management for improving metabolic health, including cardiometabolic risk factors, regardless of whether weight loss is the primary goal.

Research supports this connection. A meta-analysis of 19 trials involving 1,193 women with PMOS found that dietary interventions were associated with improvements in insulin resistance and measures of body composition. Another meta-analysis of randomized trials found that some dietary interventions were associated with improvements in reproductive outcomes in women with PMOS, although the authors noted substantial variation between dietary approaches and individuals.

What should a fertility-supportive diet contain?

There is no universally proven “best fertility diet.” Current evidence supports focusing on nutrient adequacy and metabolic health, rather than a rigid food list.

1. Protein: the foundation for reproductive tissue

Protein supplies amino acids required for cellular structure, enzymes, transport proteins and tissue maintenance.

Eggs, fish, meat, seafood and dairy can provide highly bioavailable protein along with nutrients such as iron, zinc, vitamin B12 and selenium.

Protein can also improve satiety and help preserve lean tissue, making it useful when dietary interventions are being used to improve body composition or insulin sensitivity.

A 2024 systematic review and meta-analysis of eight trials involving 300 women with PMOS found that higher-protein diets reduced fasting insulin and, to a lesser extent, HOMA-IR compared with isocaloric balanced diets. However, the evidence does not establish a specific high-protein prescription for every woman with PMOS.

2. Folate: essential before conception

Folate is required for DNA synthesis, cell division, and one-carbon metabolism. Its importance becomes particularly critical around conception because inadequate folate increases the risk of neural tube defects.

This is why preconception nutrition should not wait until pregnancy is confirmed.

The American College of Obstetricians and Gynecologists recommends folic acid supplementation for women of reproductive age, with 400 micrograms per day appropriate for average-risk women; higher doses may be indicated in specific high-risk circumstances under medical guidance. ACOG also recommends assessing nutritional adequacy for nutrients including iron, calcium, vitamin B12 and vitamin D during prepregnancy counselling.

Food sources of folate include leafy green vegetables, liver and legumes, although food intake does not replace the clinical recommendation for folic acid supplementation before conception.

3. Iron and vitamin B12: support cellular function

Iron is required for haemoglobin production, oxygen transport and numerous cellular enzymes. Severe iron deficiency can impair normal physiological function and is particularly relevant to women with heavy menstrual blood loss.

Vitamin B12 is involved in DNA synthesis, red-blood-cell formation and neurological function. It also interacts closely with folate metabolism.

Eggs, meat, seafood and dairy can provide B12, while iron is found in a particularly bioavailable form in meat and seafood.

Importantly, supplementation should be based on individual requirements. More is not automatically better, and excessive iron can be harmful.

4. Zinc, selenium and magnesium

Zinc participates in DNA synthesis, protein synthesis and reproductive cellular processes. It is found in shellfish, meat, eggs and dairy.

Selenium is incorporated into selenoproteins involved in antioxidant defence and thyroid hormone metabolism. Seafood, eggs and meat are useful dietary sources.

Magnesium participates in hundreds of enzymatic reactions, including those involved in energy metabolism and cellular signalling. Nuts, seeds, leafy greens and seafood provide dietary magnesium.

These nutrients are biologically relevant to reproduction, but it is important to distinguish nutrient adequacy from supplementation as a fertility treatment. Evidence for routine high-dose supplementation is not strong enough to recommend indiscriminate use.

5. Omega-3 fatty acids and reproductive metabolism

Fatty fish such as sardines, salmon and mackerel provide EPA and DHA. These fatty acids are structural components of cell membranes and participate in lipid and inflammatory signalling.

Research in PMOS has found that omega-3 supplementation can improve some metabolic parameters, including triglycerides and insulin-related measures, but evidence for direct improvements in fertility remains less certain. An umbrella review of randomized-trial meta-analyses found moderate-certainty evidence for some metabolic benefits of fish oil and omega-3 supplementation in PMOS, while concluding that there was no high-certainty evidence that dietary interventions alone improve reproductive outcomes across PMOS populations.

This distinction matters: supporting metabolic health is not the same as claiming that a particular supplement increases pregnancy rates.

What about carbohydrates?

For someone interested in foods to improve fertility, carbohydrate quality and metabolic response deserve attention.

Refined carbohydrates and added sugars can produce a relatively rapid rise in blood glucose and insulin. In people with insulin resistance, repeated high insulin demand may contribute to the metabolic environment associated with PCOS.

Evidence from dietary trials in PCOS suggests that lower-carbohydrate and lower-glycaemic-index/load approaches can improve certain metabolic measures, although the certainty of evidence varies and no single carbohydrate prescription has been established as universally superior.

A metabolic-health approach therefore focuses on reducing dependence on refined carbohydrates while building meals around protein, nutrient-dense vegetables and appropriate whole-food fats.

Fertility nutrition applies to men too

Reproductive health is not exclusively a female-health issue.

Sperm production requires continuous cell division, substantial energy metabolism and protection against oxidative damage. Adequate protein, zinc, selenium, folate, vitamin B12, omega-3 fatty acids and other nutrients contribute to normal physiological processes involved in male reproductive function.

Metabolic dysfunction can also affect male reproductive health. Obesity, insulin resistance and metabolic syndrome have been associated with altered reproductive hormones and impaired semen parameters in observational research. 

Therefore, preconception nutrition should involve both partners rather than placing the entire nutritional burden on women.

The bigger picture: fertility is metabolic, hormonal and nutritional

The most useful way to think about a fertility diet is not as a collection of “fertility superfoods.”

Think instead about creating the physiological conditions required for normal reproductive function:

Adequate protein → provides amino acids for cellular structure and function

Sufficient micronutrients → support DNA synthesis, energy metabolism, oxygen transport and antioxidant systems

Quality dietary fats → provide essential fatty acids and support cell membranes

Better metabolic health → supports insulin and hormonal regulation

Adequate energy availability → avoids the reproductive consequences of both excessive energy availability and severe energy restriction And for women with PMOS, lifestyle management should be individualised. The international guideline specifically recognises that healthy lifestyle behaviours can provide benefits even without weight loss and recommends approaches that are sustainable and tailored to the individual.

The bottom line

The best fertility foods are not necessarily exotic foods or expensive supplements.

Eggs, fish, seafood, meat, dairy, leafy greens, nuts and seeds can provide many of the nutrients involved in reproductive physiology. More importantly, the overall dietary pattern should support adequate nutrition and healthy metabolic function.

For people with PCOS or insulin resistance, this metabolic perspective becomes especially relevant because insulin signalling and reproductive hormone pathways are closely interconnected.

Food cannot guarantee fertility. Infertility has many causes, including anatomical, genetic, endocrine, ovarian, testicular and age-related factors.

But nutrition can help create a healthier physiological environment for reproduction.

Support insulin sensitivity.Meet nutrient requirements.Prioritise protein and nutrient-dense whole foods. Address deficiencies when they exist.And treat reproductive health as part of whole-body metabolic health.

Get over carbs. Get into metabolic health.