Healthy Childhood Diet Linked to Later Menarche, Independent of BMI and Height

A recent study published in Human Reproduction has revealed that girls who maintain a healthy diet during childhood are likely to experience the onset of their menstrual periods at a later age compared to those who follow a less nutritious diet. This relationship remains consistent regardless of the girls' body mass index (BMI) or height, both of which have previously been associated with earlier menarche.

The implications of these findings are significant as early menarche is linked to an increased risk of various health issues in later life, including diabetes, obesity, breast cancer, and cardiovascular diseases. The study emphasizes the importance of providing children and adolescents with access to healthy food options, particularly through school-based meal programs that adhere to evidence-based nutritional guidelines.

Conducted as part of the Growing Up Today Study (GUTS), the research involved over 7,500 children aged between 9 and 14 years, who were enrolled in two waves during 1996 and 2004. The researchers tracked these participants until 2001 and 2008, respectively. For the first time, the study specifically examined the correlation between dietary habits and the age at which girls experience their first menstrual period (menarche), while also analyzing the potential impact of BMI.

The lead researcher noted that earlier findings from the Nurses' Health Study II indicated a higher risk of breast cancer among individuals consuming diets that promote inflammation during adolescence and early adulthood. This prompted further investigation into whether dietary intake during earlier life stages could influence breast cancer risk factors, including the age at menarche.

Throughout the study, participants filled out questionnaires detailing their dietary habits upon entering the study and every one to three years thereafter. The researchers assessed the dietary patterns using two established frameworks: the Alternative Healthy Eating Index (AHEI) and the Empirical Dietary Inflammatory Pattern (EDIP). The AHEI assigns higher scores for healthier food choices, such as fruits, vegetables, and whole grains, while lower scores are given for less healthy options, including red and processed meats and trans fats. Conversely, the EDIP evaluates diets based on their potential to cause inflammation in the body.

Among the participants, 6,992 girls (93% of the total cohort) reported the onset of their first menstrual period during the study. Analysis of the collected data indicated that the top 20% of girls with the highest AHEI scores, indicative of healthier diets, were 8% less likely to experience menarche within the next month than those in the bottom 20% of AHEI scores. In contrast, the 20% of participants with the highest EDIP scores, reflecting a more inflammatory diet, were 15% more likely to report their first period within the same timeframe.

The findings demonstrate a clear association between dietary patterns and the age at which girls begin menstruation, underscoring the importance of a nutritious diet irrespective of body size. Given that an earlier onset of menstruation is associated with a range of adverse health outcomes, the researchers emphasize that this period in a girl's life may be crucial for mitigating long-term health risks.

Moving forward, the research team plans to investigate how dietary patterns and body sizes during childhood and adolescence relate to menstrual cycle characteristics in adulthood. Strengths of the study include its prospective design, which collected detailed dietary data over time and allowed for an examination of BMI's influence on menarche age.

However, the study does have limitations, including the reliance on self-reported questionnaires for dietary intake and menstruation onset, which may introduce errors. Additionally, the study population was predominantly white, limiting the ability to assess potential racial differences in the results.

In summary, the findings suggest that dietary choices made in childhood and adolescence have far-reaching implications for women's health. A balanced diet rich in fruits, vegetables, whole grains, and healthy fats, while minimizing the intake of processed foods, can benefit health throughout one's life.