Scientific news – April

Regular consumption of fruit and vegetables is linked to a lower risk of certain types of cancer. However, the evidence regarding the specific effects of organic fruit and vegetables remains inconclusive. A recent study conducted on the NutriNet-Santé cohort examined the impact of replacing conventional fruit and vegetables with organic produce on cancer risk. The results indicate that replacing 100 g per day is associated with a 10% reduction in the risk of postmenopausal breast cancer. On the other hand, no clear relationship was observed with regard to the overall risk of cancer. This study therefore highlights the need for further research to better characterise the potential role of organic foods in cancer prevention.

A child’s diet not only influences growth and development but also helps to establish healthy eating habits for life. A Danish cohort study followed more than 800 children to investigate the link between their eating habits at the age of 3 and those observed at 10-11 years of age. The authors noted that habits formed between the ages of 7 months and 3 years tend to persist in the long term. Thus, a higher intake of healthy foods (fruit, vegetables, dairy products, wholemeal bread) is associated with a diet of higher nutritional quality at the age of 10-11 years. On the other hand, a high intake of sugar-sweetened beverages, snacks or ready meals is associated with poorer dietary quality in older children. Taking action from an early age to establish healthy eating habits is therefore a key factor in long-term health.

A recent study compared the environmental impact of the Mediterranean diet with that of the Western diet using a life cycle assessment This method was applied to two menus representative of each diet, focusing only on the food production phase, which is the main source of impacts. The Western diet had a greater impact for 12 out of the 15 environmental indicators applied. In particular, the impact on climate change was estimated at 2.19 kg CO₂eq for the Mediterranean diet, compared with 3.53 kg CO₂eq for the Western diet. This difference can be explained by a higher proportion of plant-based foods and lower consumption of animal products in the Mediterranean diet. However, in relation to agricultural cropping practices, the indicators for water use and human toxicity-cancer were higher for the Mediterranean diet. The authors thus emphasise the need to consider production practices in addition to the mere composition of diets.

Pregnancy is a period of increased risk for mental health problems among mothers. A recent study therefore investigated prenatal depression in pregnant women in their third trimester. The cohort consisted of low-income Hispanic women living in California. This group is particularly vulnerable to depressive disorders. Dietary data were collected in order to assess the extent to which participants adhered to an unbalanced diet or a healthy diet. The latter was specifically characterised by a high intake of fruit, vegetables and vegetable oils. Participants who adhered most closely to the healthy diet had a 59% lower risk of prenatal depression than those who did not. The authors therefore emphasise the need for access to a balanced diet and nutritional advice right up until the end of pregnancy.

A cohort study in the United Kingdom examined the inequalities found in the consumption of fruit and vegetables. The authors adopted an intersectional approach combining educational attainment, gender, age and ethnic background. Nearly 63% of the population did not meet the recommended intake levels. In particular, men, younger people, those with a low level of education and those from ethnic minority backgrounds are at increased risk of inadequate intake. Educational attainment appears to be the most significant factor. However, the study did not reveal any strong synergistic effect between these factors. Their influences combine without reinforcing one another. Taken together, these findings highlight the need for specific policies designed to improve access to fruit and vegetables and reduce these inequalities.