THE MOST UNDERRATED FERTILITY FACTOR OF ALL IS ON YOUR PLATE

When fertility comes up, the conversation tends to follow a familiar script. Age. Hormone panels. Ovulation tracking. Semen analysis. Supplements. Scans. These matter, and they deserve the attention they get.

What rarely makes the script is the thing that happens three times a day. Food is the raw material the body uses to build eggs and sperm, regulate hormones, manage inflammation, and keep blood sugar steady. A growing body of research suggests that what people eat before conception is associated with how easily they conceive, and the evidence points to something that applies to both partners, not only to women.

One honest note before going further. Diet is not a guarantee, and infertility has many causes that no meal can fix. If you have been trying for a while, particularly if you are over 35, getting evaluated should not wait on a diet change. What follows is about stacking the odds in your favor, not about blame.

What the Research Shows

The strongest finding in the female fertility literature comes from a systematic scoping review of 36 studies, most of them prospective, examining how preconception diet relates to fertility. Of all the dietary exposures assessed, adherence to a Mediterranean diet showed the strongest and most consistent association with improved clinical pregnancy rates. Reducing trans fats, saturated fats, and discretionary foods like fast food and sugar sweetened beverages was associated with better live birth and clinical pregnancy outcomes.

A randomized trial protocol in women undergoing IVF noted that a Mediterranean diet has been reported to increase pregnancy rates by up to 40 percent, though that figure comes from earlier observational work, and large randomized trials remain limited. That caveat matters. Most of the evidence here is observational, which can show association but cannot prove cause. But the pattern repeats across studies, populations, and methods, and that consistency is why nutrition keeps showing up in the fertility literature.

Why Food Matters Biologically

Eggs and sperm are not static. Both are built and matured over a period of roughly three months before ovulation or ejaculation, which means the diet of the preceding months is part of what they are made from.

Several mechanisms explain why food matters. Oxidative stress, an imbalance between free radicals and the body’s antioxidant defenses, is a major factor in both male and female infertility, and antioxidant rich eating patterns may help counter it. Chronic inflammation and blood sugar swings interfere with ovulation and hormone signaling. And the fats in the diet become part of cell membranes, including those of eggs and sperm, which is part of why the type of fat matters so much.

The Pattern That Helps: A Mediterranean Style Plate

The Mediterranean diet is built around vegetables, fruit, legumes, whole grains, nuts, olive oil, and fish, with limited processed food and red meat. It consistently comes out on top in fertility research, and in men the evidence is specific.

A 2025 Italian study in the journal Nutrients assessed 358 men at one clinic. Men who followed a Mediterranean diet more closely had better sperm concentration, total count, motility, viability, and the percentage of normally shaped sperm. Moderate and high adherence were associated with substantially lower odds of low sperm count. A 2025 systematic review and meta analysis reached a similar conclusion, with Mediterranean style eating associated with better sperm count, motility, and morphology.

There is a caveat worth stating clearly. In the research on men, the benefit is established for semen parameters, but evidence that it improves actual pregnancy outcomes is weaker. Better sperm numbers are a good sign. They are not the same as a guaranteed pregnancy.

The Pattern That Hurts: Ultra Processed Food

The same Italian study found the reverse for ultra processed foods. As the share of calories from ultra processed foods rose, sperm concentration, total count, progressive motility, and normal morphology all fell. Men in the third and fourth quartiles of ultra processed intake had roughly three and a half to four and a half times the odds of low sperm count compared with those who ate the least. The authors note the limits: it was a single clinic, a cross sectional design, and diet was measured by questionnaire and one 24 hour recall.

These foods are typically high in sugar, refined fats, salt, and additives, and low in the fiber, antioxidants, and healthy fats that fertility seems to depend on. The finding fits a broader pattern across preconception nutrition research.

Trans Fats: The Clearest Villain

If one dietary component stands out as worth avoiding, it is trans fat. Trans fats are the artificial fats found in some fried foods, margarines, and packaged snacks. Harvard research cited by fertility clinics found that consuming around 4 grams of trans fat per day was associated with a 73 percent higher risk of ovulatory infertility. The proposed mechanism is that trans fats disrupt insulin sensitivity and promote inflammation, both of which interfere with ovulation. This is observational data, but it is among the most consistent findings in the field, and trans fat avoidance carries no downside.

Omega 3 Fats and Embryo Quality

Omega 3 fatty acids, found in fatty fish, walnuts, flax, and chia, are among the most studied nutrients in fertility. In the large scoping review, higher omega 3 intake was associated with improved fecundity, meaning the likelihood of conceiving in a given cycle. In one study of women conceiving through assisted reproduction, those in the top quartile of DHA and EPA intake had a 54 percent probability of live birth compared with 36 percent in the bottom quartile, although total omega 3 intake alone showed no effect.

A randomized, single blind trial of 180 women undergoing IVF found that following a pro fertility dietary pattern plus daily omega 3 supplementation for 60 days significantly improved fertilization rate and embryo quality. Fertility specialists commonly recommend two to three weekly servings of lower mercury fish such as salmon, though most people eat less than that.

Sugary Drinks, Processed Meat, and the Evidence That Is Still Mixed

Not every finding is equally solid, and it is worth being honest about the gray areas.

Sugar sweetened beverages, particularly sodas and energy drinks, have been linked to lower fertility in both men and women in some studies, while fruit juice appeared to have no effect. The scoping review found the evidence on sugary drinks less consistent than the evidence on trans fats or the Mediterranean pattern, so this is a reasonable thing to cut back on rather than a proven cause.

Processed meats, such as bacon, sausage, and deli meats, have been associated with poorer sperm quality, and one study found that men eating fewer than 1.5 servings per week had better chances of achieving pregnancy. This comes from a smaller body of evidence and should be held loosely.

Seafood, dairy, and soy showed inconsistent results across the few studies that examined them, so there is no reliable blanket rule for those foods.

What About Supplements

Many people assume the answer to fertility nutrition is a supplement. The research is more modest than the marketing.

Studies on folate, vitamin D, and antioxidant intake in women undergoing IVF have produced mixed results. A prospective cohort of 349 women found no association between dietary antioxidant intake and live birth, and several folate studies found no appreciable relationship with IVF outcomes. Higher preconception vitamin D levels were associated with better pregnancy outcomes in one retrospective cohort of 218 women. An umbrella review found that multiple micronutrients and antioxidants were associated with higher live birth rates, but the certainty of that evidence was very low. Early research on coenzyme Q10 suggests it may support egg quality in older women by supporting mitochondrial health, but this is still emerging.

The honest summary is that folate before conception remains well established for preventing neural tube defects, and it belongs in any preconception plan. Beyond that, the evidence for fertility specific supplements is thin, and a food first approach is better supported than a pill.

How to Eat for Fertility in Practice

None of this requires a special protocol. The research points toward a pattern, not a rulebook.

Build most meals around vegetables, legumes, whole grains, and fruit. Cook with olive oil. Eat fatty fish or other omega 3 sources several times a week. Add nuts and seeds. Choose whole foods over packaged ones where you can, which covers the ultra processed foods and trans fats the research warns about. Cut back on sugary drinks and processed meats. Do this for both partners, since the research on sperm is as strong as the research on eggs.

Because eggs and sperm mature over roughly three months, the most useful window to start is well before trying to conceive. But starting at any point is better than waiting for the perfect moment.

The Bigger Picture

The fertility industry is organized around testing and intervention, and those are valuable. But it has historically underplayed the one factor that every person controls daily and that research keeps associating with better outcomes.

Food will not solve every case of infertility, and no one should be made to feel that their diet caused a struggle that has many possible causes. What the research supports is more hopeful and more practical than blame: a pattern of eating that is good for the heart, the gut, and the metabolism also appears to be good for eggs and sperm, and it costs nothing to begin.

The most underrated fertility factor is not a secret. It is simply the plate in front of you, and the months of plates that came before it.

Scientific Sources

1. Stocker, L., et al. Nutrition for Preconception Health and Fertility. Annals of Nutrition and Metabolism, 2025.
2. Assessing the Influence of Preconception Diet on Female Fertility: A Systematic Scoping Review of Observational Studies. Human Reproduction Update, 2023.
3. Role of Mediterranean Diet and Ultra Processed Foods on Sperm Parameters: Data from a Cross Sectional Study. Nutrients, 2025.
4. News Medical. Mediterranean Diet Boosts Sperm Health While Ultra Processed Foods Lower Fertility, Study Finds. news-medical.net, 2025.
5. Influence of the Mediterranean Diet on Seminal Quality: A Systematic Review. PMC.
6. Agarwal, A., et al. Mediterranean Diet, Semen Quality, and Medically Assisted Reproductive Outcomes in the Male Population: A Systematic Review and Meta Analysis. 2025.
7. Effect of a Pro Fertility Diet Combined with Omega 3 Supplementation on Embryo Quality in Infertile Women Undergoing IVF: A Randomized Controlled Trial. ScienceDirect, 2026.
8. Diet in Assisted Reproductive Technology: What Should We Recommend? A Systematic Review. Reproductive BioMedicine Online, 2026.
9. A Randomised Controlled Trial of a Preconceptional Dietary Intervention in Women Undergoing IVF Treatment (PREPARE Trial). PMC.
10. The Role of Nutrient Supplements in Female Infertility: An Umbrella Review and Hierarchical Evidence Synthesis.
11. Atlantic Fertility. Diet and Nutrition for Fertility: What Actually Helps. atlanticfertility.com.
12. Carrot Fertility. Fertility and Nutrition: An In Depth Guide to Optimize Reproductive Health. get-carrot.com, 2025.
13. IVF Center Hawaii. Nutrition Tips to Support Fertility Health. ivfcenterhawaii.com, 2025.
14. Evewell. What to Eat Before and During IVF. evewell.com, 2026.