Dietary protein intake linked to female fertility

Investigating the role of dietary protein intake and liver function in female fertility.

MedWire News: Women with protein-deficient diets may be lowering their fertility, suggest study findings showing that expression of estrogen receptors in the liver critical for maintaining fertility is regulated by dietary amino acids.

“This is the first time it has been demonstrated how important the liver is in fertility,” said lead study author Adriana Maggi (University of Milan, Italy). “The idea that diet may have an impact on fertility isn’t totally new, of course, but this explains how diet, and especially a diet poor in protein, can have a direct influence.”

The researchers administered a 40% calorie-restricted (CR) diet to adult female ice for 4 weeks, resulting in significantly decreased liver estrogen receptor (ER) activity.

These mice and a group lacking ERs in their liver showed a significant decline in blood insulin-like growth factor (IGF-1) to levels inadequate for the correct proliferation of the uterus lumen epithelium and progression of the estrous cycle.

When the CR mice were fed a 40 percent amino-acid-enriched diet, the reproductive cycle returned to normal functioning. Dietary fats and carbohydrates had no effect on ERs or fertility.

Given the liver’s role as a central coordinator of metabolism and involvement in the production of a number of hormones, drugs that selectively target the liver may solve many metabolic and hormonal problems, conclude Maggi and team.

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