DASH, Mediterranean, and Plant-Based Diets and Cancer Risk in Women: A Narrative Review Based on Diet Quality Indices

Cancer remains a major public health challenge among women worldwide, and diet quality may play an important role in cancer prevention. This narrative review synthesized evidence on the association between standardized diet quality indices-the DASH Score, Mediterranean Diet Score, and plant-based diet indices-and the risk of selected cancers in women, focusing on breast, colorectal, and ovarian cancer. English-language publications from 2020 to 2026 were reviewed, supplemented by key earlier methodological and epidemiological sources. The most consistent inverse associations were observed for colorectal cancer in relation to the DASH and Mediterranean dietary patterns, and for breast cancer in relation to healthful plant-based diets assessed using the hPDI. Evidence for ovarian cancer remains limited and inconclusive. Across dietary patterns, the findings indicate that overall diet quality, including the quality and processing level of plant-based foods, may be more relevant than the proportion of plant foods alone. The available evidence is limited mainly by heterogeneity in index definitions, predominance of observational designs, dietary assessment errors, and residual confounding. Overall, high-quality dietary patterns may be relevant to cancer prevention in women, although the strength and consistency of associations vary by cancer site and dietary assessment approach.