Diets high in fat linked to major brain health issue in women

Women, but not men, may suffer from a serious brain health issue as a consequence of eating high-fat diets, according to a new study. The issue concerns something called hippocampal neurogenesis, which is the process in which the brain forms new neurons in the part of the brain that controls certain emotional processes and memory. Impairment in this process may be a driving factor in dementia and depression.

The link between impairment to hippocampal neurogenesis and Alzheimer's disease is a known one. Many studies over the years have evaluated this association, finding that hippocampal neurogenesis is substantial in humans and may have an overall large impact on cognitive function. A new study from the Society for Neuroscience has found that high-fat diets may have sex-specific impacts on this new neuron growth.

According to the researchers, female mice fed a high-fat diet for 18 weeks experienced impaired hippocampal neurogenesis; the same brain health issue wasn't observed in male mice, however. Both the male and female mouse groups experienced high blood sugar and weight gain as a consequence of the high-fat diet, however.

The researchers found that male mice fed the high-fat diet had the same number of new and growing neurons as male mice in the control (non-high-fat diet) group. The female mice, however, were found to have fewer new and growing neurons in the hippocampus. The findings join past research that has linked obesity to increased risk of Alzheimer's disease and depression.

The study explains that the impairment of hippocampal neurogenesis may explain why women are more likely to experience greater levels of cognitive decline when suffering from depression or Alzheimer's disease compared to men. Past studies have also found links between diets high in saturated fat and depression and between high-fat diets and increased hunger.