The body of evidence about nuts and pregnancy and fertility continues to grow, with new local and international research papers regularly published.

Body of evidence

A greater adherence to the Mediterranean diet supplemented with extra virgin olive oil and nuts during pregnancy is associated with improved offspring health at six years of age.
In this study, 1,292 women undertook a Mediterranean diet (MedDiet), supplemented with extra virgin olive oil (EVOO) and nuts, from early on in pregnancy (intervention group, or IG). A control group (CG) of 516 pregnant women followed a fat-restricted MedDiet. A total of 1,808 (81.2%) of their children were analysed at 6 years postpartum. It found a higher degree of maternal adherence to the MedDiet during pregnancy is associated with a reduction in the rates of bronchiolitis and atopic dermatitis in offspring. It also showed that intake of nuts and EVOO is associated with a higher adherence to the Mediterranean pattern, with health benefits for the offspring to at least 6 years of age.

Maternal nut and fish consumption during pregnancy and child risky decision-making at 11 years old. (Ruiz-Rivera et al, 2025).
This mother-child population-based birth cohort study assessed whether nut and fish consumption during pregnancy (the first trimester) is associated with impulsivity and risky decision-making until pre-adolescence. It involved 1,386 healthy pre-adolescents and their mothers. Among the findings, children whose mothers consumed the most nuts (the highest nut intake tertile, with a median weekly intake of 73.4g) showed a significantly lower number of risky decisions, compared to those at the lowest tertile. It concluded that a higher nut intake during early pregnancy may be related with less risky decision-making in the 11-year-old children.

Nuts and nutritional factors in management of male fertility: A review. (Nazari et al, 2024).
This narrative review summarises the literature on nuts and male fertility. The findings suggest a beneficial role for reproductive health, with evidence linking nut consumption with better semen quality and fertility in men. The authors also point out that the improvement in lipid stability, oxidative stress, inflammation indicators, and endothelial function, with nut consumption, can potentially contribute to better reproductive health, particularly in relation to age-dependent decreases in sperm quality and fertility.

Nut consumption and fertility: A systematic review and meta-analysis. (Cardoso et al, 2023).
This systematic review and meta-analysis, of four studies involving 875 participants, explored the link between nut intake and fertility in males and females. The meta-analysis showed that daily consumption of at least two servings of nuts (≥ 60g nuts/day) increased sperm motility, vitality, and morphology (within a typical Western-style diet), compared with controls, but had no effect on sperm concentration. The authors say more high-quality trials on nut intake as a strategy for infertility treatment are needed, including in females.

Nutritional interventions for male reproductive health: A comprehensive review on the impact of almonds, walnuts, and cashew nuts. (Hamza et al, 2024).
This review suggests a potential link between almonds, walnuts, and cashew consumption, and improved male reproductive health. This is thanks to the variety of bioactive compounds, including vitamin E, folate, zinc, copper, omega-3 fatty acids, and polyphenols they contain, which may help improve sperm production and quality, and protect against oxidative stress. These nuts may also help reduce inflammation – a known contributor to reproductive disorders and infertility in males. However, further well-designed clinical studies are needed in this area.

Dietary intake of poly-unsaturated fatty acids, their food sources and fertility in females and males: A preconception prospective population-based cohort study. (Schipper et al, 2025).
This prospective cohort study, involving 830 females and 651 males, assessed peri-conception dietary intake at a median of 12.4 weeks gestation. Among the findings, higher dietary intake of omega-3 PUFAs and a lower omega-6 to omega-3 PUFA ratio were associated with increased fecundability and decreased subfertility risk in females, independent of the dietary intake of the male partner. The strongest effects were present for DHA and ALA. In males, a higher dietary intake of nuts and seeds was associated with increased fecundability and decreased subfertility risk, independent of the dietary intake of the female partner.

Mediterranean diet adherence and health-related quality of life during pregnancy: Is the Mediterranean diet beneficial in non-Mediterranean countries? (Flor-Alemany et al, 2024).
This study examined the association of MedDiet adherence and MedDiet components with health-related quality of life in 138 pregnant women from Spain and 302 from Sweden. Among the findings, greater MedDiet adherence throughout gestation was associated with lower pain during pregnancy, in both Mediterranean and non-Mediterranean populations. Specifically, a greater intake of fibre, fish, fruits, nuts, and legumes seemed to explain these associations.

Soy foods and nuts consumption during early pregnancy are associated with decreased risk of gestational diabetes mellitus: A prospective cohort study. (Pang et al, 2022).
Consumption of soy foods and nuts were independently inversely associated with the risk of gestational diabetes mellitis (GDM) during early pregnancy (6-14 weeks) among women based in China. Specific to nuts, it found that, compared with those who didn’t consume nuts, those who ate the most (that is, women in the highest tertile of nut intake) had a 35% reduced risk of GDM in early pregnancy. This prospective cohort study involved 1,495 pregnant women, of which 529 were diagnosed with GDM.

Modeling the effect of environmentally sustainable food swaps on nutrient intake in pregnant women. (Wang et al, 2021).
This research looked at the impact on nutrient intakes of replacing commonly-consumed foods in pregnancy with environmentally-sustainable alternatives. With the highest gashouse gas emissions (GHG), beef was selected as the reference food. The most pronounced reductions in CO₂ emissions were from replacing beef with tofu, legumes, and nuts. For instance, replacing 1 serve/week of beef with an isocaloric serve of nuts (18g) during pregnancy could reduce GHG emissions by 383kg CO₂ equivalents, and increase folate (+10.2µg/serve) and fiber (+1.1g/serve) – with a small decrease in iron intake (-1.1mg/serve). The researchers say simple dietary swaps can noticeably reduce environmental impact, without compromising nutrient intake in pregnancy.

Effect of nut consumption on erectile and sexual function in healthy males: A secondary outcome analysis of the FERTINUTS randomized controlled trial. (Salas-Huetos et al, 2019).
Compared to the control group, a significant increase in the orgasmic function (p-value = 0.037) and sexual desire (p-value = 0.040) was observed during the nut intervention. No significant differences in changes between groups were shown in peripheral concentrations of NO and E-selectin. Including nuts in a regular diet significantly improved auto-reported orgasmic function and sexual desire.

Effect of nut consumption on semen quality and functionality in healthy men consuming a Western-style diet: a randomized controlled trial. (Salas-Huetos et al, 2018).
Snacking on a handful of nuts can improve male fertility. The study demonstrated that men who snacked on nuts every day experienced significant improvement in sperm quality parameters. The RCT showed that these improvements resulted from consuming 60 grams per day of nuts (30g of walnuts, 15g of almonds and 15g of hazelnuts), compared to consuming no nuts.

Hazelnut consumption improves testicular antioxidant function and semen quality in young and old male rats. (Kara et al, 2019).
Hazelnut supplementation in the diets of young and old rats significantly improved testicular function and semen quality.

Maternal nut intake in pregnancy and child neuropsychological development up to 8 years old: A population-based cohort study in Spain. (Gignac et al, 2019).
In the first of its kind, a study led by the Barcelona Institute for Global Health found children, whose mothers ate more nuts during the first trimester of pregnancy, achieved the best results in tests measuring cognitive function, attention capacity and working memory.