(P16-041-23) Combined Oral Contraceptive Use Alters the Effects of Egg Intake on Lipoprotein Profiles, Without Impacting Effects on Insulin Resistance, Inflammation, or Choline Status

Objectives: Combined oral contraceptives (COC) are reported to adversely impact cardiometabolic risk profiles. However, little is known about how COC use can impact an individual’s response to dietary interventions aimed at altering cardiometabolic biomarkers. Thus, we investigated the effects of COC use on markers of lipoprotein metabolism and insulin resistance (IR) in response to whole egg vs. egg white intake – foods that differentially alter cardiometabolic profiles.

Methods: Young, healthy women (18-35y, BMI < 30kg/m² or < 40% body fat, COC users: n = 11, non-users: n = 9) participated in a randomized, crossover intervention trial in which they consumed an egg-free diet for 4 weeks, followed by randomization to either a 3 whole egg/day or 3 egg whites/day diet for 4 weeks. Participants were then switched to the alternative whole egg or egg white diet treatment, separated by a second egg-free diet washout period. Fasting serum samples were collected at the end of each diet period to measure cardiometabolic risk factors.

Results: Whole egg intake increased HDL-cholesterol (HDL-C) in COC users, yet decreased HDL-C in COC nonusers, corresponding to a trend toward increased total cholesterol:HDL-C ratios in nonusers. Similarly, there was a trend toward increased large HDL particle concentrations following whole egg intake in COC users, and increased serum levels of small triglyceride-rich lipoproteins in nonusers compared to COC users. While fasting glucose did not differ by diet treatment or COC use, COC users trended toward higher lipoprotein-insulin resistance (LP-IR) scores, which take into account IR and lipoprotein profiles, independent of diet. Regardless of COC use, whole egg intake increased serum glycine levels without changing pro-inflammatory glycoprotein acetylation - measures that are inversely and positively associated with IR risk, respectively. Regardless of COC use, whole egg intake trended toward increases serum choline without changing trimethylamine N-oxide levels.

Conclusions: Our findings indicate that egg intake differentially impacted lipoprotein profiles in COC users vs. nonusers, and that COC use did not adversely impact markers of IR, inflammation, or choline status from egg consumption.

Funding Sources: This study was funded by an Agriculture and Food Research Initiative Grant from the USDA National Institute of Food and Agriculture.