An ongoing discussion is taking place on various platforms, as well as in interpersonal settings, about what constitutes healthy food, what we should or should not consume, and which diet we should adhere to. As this discussion continues, so does the dissemination of nutrition information.

The WHO describes a healthy diet as being “essential for good health and nutrition”. A healthy diet protects against cardiovascular disease, type 2 diabetes mellitus and steatotic liver disease, among other noncommunicable diseases. WHO recommends following a daily diet comprised of a variety of whole foods, eating less fat and sugar, and reducing salt intake. Moreover, experts advise avoiding sugar-sweetened beverages and ultra-processed foods — the definition1 of which remains a subject of debate — as much as possible2.

Thus, at Nature Reviews Gastroenterology & Hepatology, we are launching a new Series of articles dedicated to ‘Nutrition’ to contribute to the discussion and provide a much-needed space for science to inform us about nutrition. In a Review article, Yolanda Sanz and colleagues3 discuss the bidirectional relationship between the gut microbiome and nutrition, as well as its role in human health. Dietary guidelines and, consequently, nutrition and public health can be improved by incorporating knowledge of microbiome–diet–host interactions into nutrition and clinical practice. Another Review offers insights into the parental diet and offspring health. Here, Chaoran Yang and colleagues summarize studies on the gut–germline and gut–neonatal axes. They discuss how changes in the diet might affect noncommunicable disease predisposition of offspring by influencing the microbiome and immune system, among others. Also in this issue, in a Comment, Fiona Malcomson and colleagues present evidence from ongoing clinical trials that investigate diet as a medicinal intervention in gastrointestinal cancer therapy, suggesting that diet modulates cancer risk and influences survivorship.

As the prevalence of obesity increases worldwide, we need to remember that there are regions in which malnutrition is widespread, either due to a lack of access to healthy food or to sufficient calories4. The figures presented in the Global Nutrition Report are staggering. According to the report, there is little progress towards global nutrition targets: in adults, no country is on course to stop obesity from rising and very few are on course to reduce type 2 diabetes mellitus. There is some progress towards childhood stunting (53 countries are on course) and childhood obesity (105 countries are on course). However, according to UNICEF’s 2025 Child Nutrition Report5, 2025 is the year in which the global prevalence of obesity in children and adolescents exceeded that of overweight.

“we are launching a new Series of articles dedicated to ‘Nutrition’”

Food is medicine, but it is also culture, equity and identity. The global rise of obesity and poor diet urges us to reshape our approach to nutrition, both in individuals and societies.