Fatty fish intake delays puberty in girls

A recent study has linked fatty fish consumption to delayed puberty in girls and red meat intake to early onset of periods.

The University of Michigan researchers evaluated six years of data from 456 girls aged 5 and 12 years participating in the Bogota School Children Cohort in Colombia and found that girls who ate red meat started their periods earlier than those who didn't, while the ones who consumed fatty fish started their menstrual cycles much later.

Study results revealed that red meat consumption ranged from less than four times a week to twice a day and girls who ate the most red meat had their first menstrual cycle at a median age of 12 years and 3 months. However, those who ate less red meat had their first period at 12 years and 8 months.

It also showed that girls who ate fatty fish like salmon, mackerel and sardines at least once a week experienced their first menstrual cycle significantly later than those who ate it once a month. Researchers found that girls who ate fatty fish most frequently had their first menstrual cycle at 12 years and 6 months.

Researchers said the findings are important because early puberty in girls has been linked to breast cancer, type 2 diabetes, heart disease and obesity.

Study author Erica Jansen said that it is an important difference because it is associated with the risk of disease later in life and because few dietary factors are known to affect the timing of puberty. This finding may also contribute to explain why red meat intake early in life is related to increased risk of breast cancer later in life.

"We cannot conclude that there is necessarily a causal role of red meat on onset of puberty from this study. However, there is a mounting body of evidence suggesting that excessive intake of red meat at different stages of life is related to a number of adverse health outcomes, especially to getting some types of cancer," added senior author Dr. Eduardo Villamor.

The study is published in the Journal of Nutrition.