According to Gram Research analysis, a 2026 cross-sectional study of 5,477 American women found that higher diet quality—measured by Mediterranean, DASH, and other healthy eating indices—was significantly associated with lower rates of infertility. Women scoring highest on all four diet quality measures had substantially reduced odds of infertility compared to those with lower diet quality scores, suggesting that eating patterns emphasizing whole foods, vegetables, and lean proteins may support fertility.
A large study of over 5,400 American women found that eating a healthier diet is linked to better fertility. Researchers looked at data from 2013 to 2020 and tested four different ways of measuring diet quality—including Mediterranean-style eating and the DASH diet. Women who scored higher on all four diet quality measures had lower rates of infertility. The study suggests that improving what you eat might be one way to support your chances of getting pregnant, though more research is needed to prove cause and effect.
Key Statistics
A 2026 cross-sectional study of 5,477 U.S. women found that higher scores on all four diet quality indices (Mediterranean, DASH, Healthy Eating Index-2020, and Alternate Healthy Eating Index) were significantly associated with lower odds of infertility.
Research reviewed by Gram showed that the association between diet quality and infertility was approximately linear across all four diet quality measures, meaning fertility benefits increased steadily as women improved their eating patterns.
In a 2026 analysis of NHANES data from 2013-2020 covering 5,477 women, the protective association between higher diet quality and lower infertility rates remained significant even after adjusting for age, BMI, smoking, alcohol use, and menstrual regularity.
The Quick Take
- What they studied: Whether eating a higher-quality diet is connected to lower rates of infertility in women
- Who participated: 5,477 women aged 18-59 years living in the United States, with dietary information collected between 2013 and 2020
- Key finding: Women with higher diet quality scores on all four tested diet patterns (Mediterranean, DASH, Healthy Eating Index, and Alternate Healthy Eating Index) had significantly lower odds of infertility, with consistent dose-response patterns
- What it means for you: If you’re trying to conceive, focusing on eating more whole foods, vegetables, fruits, and lean proteins while limiting processed foods may support fertility. However, this study shows association, not proof that diet causes better fertility—other factors matter too.
The Research Details
This was a cross-sectional study, which means researchers collected information from a large group of women at one point in time and looked for patterns. They used data from the National Health and Nutrition Examination Survey (NHANES), a long-running government health study that tracks what Americans eat and their health outcomes.
Researchers measured diet quality in four different ways using 24-hour dietary recall—asking women to remember everything they ate in the previous day. The four diet quality measures were: the Mediterranean diet score (emphasizing olive oil, fish, and vegetables), the Healthy Eating Index-2020 (a government standard for healthy eating), the Alternate Healthy Eating Index (a modified version focusing on whole grains and healthy fats), and the DASH diet score (designed to lower blood pressure).
They then used statistical models to see if women with higher diet quality scores had lower rates of infertility, while accounting for other important factors like age, weight, smoking, alcohol use, and menstrual regularity.
This research approach is important because it uses real-world data from a nationally representative sample of American women, making the findings more applicable to everyday people. By testing four different diet quality measures, the researchers could see if the connection between diet and fertility was consistent across different healthy eating patterns. The statistical adjustments for other factors help isolate the diet effect from other things that influence fertility.
Strengths: Large sample size (5,477 women), nationally representative data, adjustment for multiple important factors, and consistent findings across four different diet quality measures. Limitations: This is a cross-sectional study, so it shows association but cannot prove that diet causes better fertility. The study relied on self-reported infertility and one-day dietary recalls, which may not perfectly represent typical eating patterns. The researchers could not account for all possible factors affecting fertility, such as specific medical conditions or partner factors.
What the Results Show
Women who scored higher on all four diet quality indices had significantly lower odds of infertility. The associations were consistent and approximately linear, meaning that as diet quality improved, infertility rates decreased in a steady pattern rather than having a sudden threshold effect.
The Mediterranean diet score showed a protective association with fertility. The Healthy Eating Index-2020, which emphasizes whole grains, vegetables, fruits, and lean proteins while limiting added sugars and sodium, was also inversely associated with infertility. Similarly, the Alternate Healthy Eating Index and the DASH diet score both showed that higher scores were linked to lower infertility rates.
All four diet quality measures showed dose-response relationships, meaning the benefit increased as diet quality improved. The researchers found no evidence of a nonlinear relationship (P for nonlinearity >0.05 for all indices), suggesting a straightforward relationship: better diet quality equals lower infertility risk.
The study controlled for numerous factors that affect fertility, including body mass index (BMI), smoking status, alcohol consumption, menstrual regularity, age at menarche (first period), and history of pelvic inflammatory disease. Even after accounting for these factors, the association between diet quality and infertility remained significant. This suggests that diet quality has an independent effect on fertility beyond what these other factors explain.
This research aligns with growing evidence that diet quality affects reproductive health. Previous studies have shown connections between specific nutrients and fertility, but this study is notable for examining multiple comprehensive diet quality measures simultaneously in a large, nationally representative population. The findings support recommendations that women of reproductive age focus on overall diet quality rather than single nutrients.
The biggest limitation is that this is a cross-sectional study, which means researchers took a snapshot in time rather than following women over years. This prevents them from proving that diet changes cause better fertility—only that they’re associated. The study relied on women’s self-reported infertility status, which may be underreported or inaccurate. Dietary data came from a single 24-hour recall, which may not represent a woman’s typical eating patterns. The study couldn’t account for all factors affecting fertility, such as specific diagnoses, partner factors, or timing of intercourse. Additionally, the study population was U.S.-based, so findings may not apply to other countries with different food availability and dietary patterns.
The Bottom Line
Women trying to conceive should consider adopting a higher-quality diet emphasizing whole foods, vegetables, fruits, whole grains, lean proteins, and healthy fats while limiting processed foods, added sugars, and sodium. The Mediterranean and DASH diet patterns are both supported by this research. Confidence level: Moderate—this study shows strong association but cannot prove causation. These dietary changes also support overall health, making them worthwhile regardless of fertility goals.
Women of reproductive age who are trying to conceive or planning to conceive should pay attention to these findings. Women with diagnosed infertility should discuss dietary changes with their healthcare provider as part of a comprehensive fertility plan. This research is less directly applicable to women not trying to conceive, though the diet quality measures studied are associated with overall health benefits. Men’s diet quality may also affect fertility, though this study focused only on women.
Dietary changes typically take several months to show effects on health markers. If you’re trying to conceive, consider giving dietary improvements at least 2-3 months before expecting to see fertility benefits, as this aligns with the timeline of egg development and reproductive hormone cycles. Combine dietary changes with other evidence-based fertility strategies and consult with a healthcare provider.
Frequently Asked Questions
Can improving my diet help me get pregnant?
Research shows higher diet quality is associated with lower infertility rates in women. A 2026 study of 5,477 women found that Mediterranean, DASH, and other healthy eating patterns were linked to better fertility outcomes. However, diet is one factor among many affecting fertility—consult your doctor for personalized advice.
What diet is best for female fertility?
This study found four diet patterns equally beneficial: Mediterranean (emphasizing olive oil and fish), DASH (limiting sodium), Healthy Eating Index-2020, and Alternate Healthy Eating Index. All emphasize whole grains, vegetables, fruits, lean proteins, and healthy fats while limiting processed foods and added sugars.
How long does it take for diet changes to improve fertility?
While this study shows association rather than timeline, fertility-related changes typically take 2-3 months to appear, aligning with egg development cycles. Dietary improvements also support overall health immediately, making them worthwhile regardless of fertility timelines.
Does this study prove diet causes infertility problems?
No. This cross-sectional study shows association between lower diet quality and infertility, but cannot prove diet causes infertility. Other factors affect fertility too. The researchers note findings should be interpreted as associative rather than causal.
Should men also improve their diet for fertility?
This study focused only on women, but research suggests male diet quality also affects fertility. Both partners improving diet quality is a reasonable approach, though consult healthcare providers for partner-specific fertility recommendations.
Want to Apply This Research?
- Track daily diet quality using a simple scoring system: count servings of vegetables, fruits, whole grains, and lean proteins daily, and note processed food intake. Aim for 5+ servings of vegetables and fruits, 3+ servings of whole grains, and 2-3 servings of lean protein daily while keeping processed foods to fewer than 2 servings.
- Start by adding one Mediterranean or DASH diet element to each meal: add olive oil to salads, include fish twice weekly, increase vegetable portions, or swap refined grains for whole grains. Track these additions in the app to build momentum and see patterns in how consistent healthy eating affects your health markers.
- Log weekly diet quality scores and any fertility-related health markers you’re tracking (menstrual regularity, energy levels, etc.). Review monthly trends to see if improved diet quality correlates with other health improvements. Share this data with your healthcare provider to inform fertility discussions.
This research shows association between diet quality and fertility outcomes, not proof of causation. Individual fertility is influenced by many factors including age, medical conditions, genetics, and partner factors. Women experiencing infertility should consult with a reproductive endocrinologist or fertility specialist for personalized evaluation and treatment. Dietary changes should complement, not replace, medical fertility care. This article is for educational purposes and should not be considered medical advice. Always discuss dietary changes and fertility concerns with your healthcare provider.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.