The Role of Diet in Women of Childbearing Age: Current Evidence Supporting Nutritional Recommendations

Background/Objectives: Nutrition during the reproductive years shapes women’s immediate health, fertility, pregnancy outcomes, and long-term offspring well-being. This position paper narratively synthesizes and critically appraises evidence on how dietary patterns, macro-/micronutrients, and supplementation influence women’s health, female fertility, and reproductive outcomes, to inform practical recommendations. Methods: We narratively reviewed recent reviews, cohort studies, clinical trials, and public-health guidance on macronutrients, key micronutrients, dietary patterns (with emphasis on the Mediterranean diet), ultra-processed food (UPF) intake, and targeted supplementation relevant to menstrual, metabolic, cardiovascular, skeletal, and reproductive outcomes. Results: Balanced, diverse diets rich in whole and minimally processed foods support hormonal regulation, ovulatory function, healthy gestation, and chronic-disease risk reduction. Priority nutrients include iron, folate, calcium, vitamin D, zinc, vitamin B12, and long-chain omega-3s (DHA), with supplementation considered when dietary intake or bioavailability is inadequate. Evidence consistently links Mediterranean-style eating to improved metabolic health, insulin sensitivity, IVF success, lower gestational diabetes risk, and favorable neonatal outcomes. High UPF consumption is associated with poorer diet quality, inflammation, adverse pregnancy outcomes, and potential reproductive impairment, warranting a reduction in favor of nutrient-dense foods. Diet also influences cardiovascular and bone health through effects on lipids, glycemia, blood pressure, and mineral/vitamin status, with fiber-rich carbohydrates, unsaturated fats (notably olive oil), and adequate calcium–vitamin D emerging as central levers. Conclusions: For women of childbearing age, a Mediterranean-aligned, minimally processed dietary pattern—tailored to individual needs and complemented by prudent use of folate, iron, vitamin D, calcium, B12, and DHA when indicated—offers robust benefits across reproductive, metabolic, cardiovascular, and skeletal domains. Public-health actions should improve access to healthy foods, curb UPF marketing, and embed personalized nutrition counseling in routine care; further longitudinal research from preconception through postpartum is needed.