Energy Density Is Lower in Exercising Women with Energy Related Menstrual Cycle Disturbances

Abstract

BACKGROUND: Previous research has demonstrated that women with energy related menstrual cycle disturbances (ERMD) including oligomenorrhea or amenorrhea, display restrictive eating patterns. Energy density is defined as the number of kilocalories (kcal) per gram of food or beverage consumed, and strategies to manipulate energy density to achieve increased satiety by incorporation of low energy dense foods into the diet have been recommended for weight loss in obese individuals. PURPOSE: To determine whether this same strategy to maintain low caloric intake is particularly prominent in exercising women with ERMD. METHODS: Volunteers in a cross-sectional study were retrospectively characterized by menstrual status into two groups: (1) ERDM (n=18), including women with oligomenorrhea or amenorrhea, and (2) Eumenorrheic Controls (EC) (n=14). Two 3-day diet records were collected one month apart and analyzed to calculate energy density and other dietary parameters. Measures of aerobic fitness, body composition, and energy balance were obtained. RESULTS: ERMD and EC were similar with respect to age (21.8±1.0 yr) and history of exercise minutes (503±110 min/week). ERMD had a lower BMI (20.2±0.7 vs. 22.5±0.4 kg/m2; p<0.05) and REE (1163±36 vs. 1286±10 kcals/day). Energy intake was similar between ERMD and EC women (1830±209 vs. 2024±159 kcals, respectively; (p=0.490)). Diets in ERMD and EC were similar when macronutrient content was compared, i.e., 265±27 vs. 266±56g/day of carbohydrates, 58±10 vs. 71±5g/day of fat, and 71±7 vs. 81±6 g/day of protein, respectively. However, energy density was lower in the ERMD women (0.69±0.06 kcal/gram) compared to the EC women (0.94±0.08 kcal/gram) (p=0.017). This difference may be driven by specific strategies to reduce fat intake. Percentage of kcals/day from fat was 25.9±1.6 vs. 30.6±1.1% (p=0.028), leading to an increase in percentage of kcals/day from carbohydrate (56.7± 1.7 vs. 50± 1.7%; p=0.021) in ERMD vs. EC, respectively. CONCLUSION: Women with ERMD may consume food with lower energy density as a strategy to successfully restrict calories and maximize satiety. Supported by the U.S. Department of Defense, Army Medical Research and Materiel Command (W81XWH-06-1-0145) and the National Athletic Training Association Foundation Grant #206GGP008