Abstract:
It is estimated that menstrual dysfunction, including amenorrhea, affects anywhere from 6-79% of active women1. Amenorrhea is defined as the absence of a menstrual cycle lasting more than three months2. Secondary amenorrhea occurs after menarche2. Primary amenorrhea is the delay of menarche past 15 yrs2. Menstrual dysfunction can negatively impact health by reducing the achievement of peak bone mineral density (BMD) or increasing the loss of BMD5. Energy imbalance due to insufficient energy intake to fuel a high energy output is one of the many factors that contribute to amenorrhea in athletic women3. It has been hypothesized that active women with menstrual dysfunction have lower energy intakes due to the consumption of low-energy dense foods4.
Energy density is a ratio of the energy (kcals) in a food and its weight (g)6. A low energy dense diet is often associated with a lower energy intake and a higher quality diet7. It is high in fruits and vegetables, low-fat dairy, and whole grains, which can be filling due to the volume of food consumed. A low energy dense diet is recommended for weight loss or maintenance due to the satiety factor of the volume of food, while being low in overall calories. Research has found that participants consume more energy when provided with energy dense food in a lab setting where ad libitum food is available for consumption6. However, for active women with high energy needs a low energy dense diet may not provide enough energy to properly fuel their activity level, activities of daily living and reproductive function, thus, leading to amenorrhea.
The purpose of this research was to compare the energy density of the diets of amenorrheic active women before and after a 6-month intervention designed to restore menstrual dysfunction and to eumenorrheic active controls. It was hypothesized that active amenorrheic athletes would have diets lower in energy density vs active eumenorrheic controls. We also hypothesized that the 6-month intervention designed to restore menstrual function would increase dietary energy density from pre-intervention levels. We also examined the macro and micronutrient (calcium, iron, folate, vitamin B6, and vitamin B12) intakes of these women.
