Dietary Cholesterol Contained in Whole Eggs is Not Well Absorbed and Does Not Affect Plasma Total Cholesterol Concentration in Men and Women: Results from Two Randomized Controlled Crossover Trials
Authors: Kim Jung Eun , Campbell Wayne W 
Published: November 2023

Whole egg is a well‐known food source of dietary cholesterol and inconsistent research findings exist about the effect of dietary cholesterol from whole egg on blood cholesterol concentration. A previous animal study reported that phosphatidylcholine in egg yolk inhibits dietary cholesterol uptake by the intestine. Therefore, in this study, we assessed the effect of co‐consuming cooked whole eggs on dietary cholesterol absorption in adults from 2 randomized controlled crossover trials.

For study 1, 16 men (mean ± SE; age: 24 ± 1 y; BMI: 24 ± 1 kg/m2) consumed a raw mixed vegetable salad (0 mg dietary cholesterol) with no egg, with 75 g cooked whole egg (CWE) (280 mg dietary cholesterol), or with 150 g CWE (560 mg dietary cholesterol). For study 2, 17 women (age: 45 ± 4 y; BMI: 25 ± 2 kg/m2) consumed cooked mixed vegetables (0 mg dietary cholesterol) with no egg or with 100 g CWE (373 mg dietary cholesterol). In both studies, blood was collected hourly for 10 hours and triacylglycerol‐rich lipoprotein (TRL) fractions were isolated. Total cholesterol and triacylglycerol concentrations in TRL fractions and plasma were analyzed and composite areas under the curve (AUCs) were calculated. Concentrations of total cholesterol and triacylglycerol within TRL fractions represent newly absorbed cholesterol and triacylglycerol.

In study 1, total cholesterol AUC0–10h in TRL fractions was not different among 150 g CWE vs. 75 g CWE vs. no egg (lsmean ± SE; 5.3 ± 1.2 vs. 4.2 ± 1.2 vs. 1.7 ± 1.2 mg • dL−1 • 10h, p = 0.11) but triacylglycerol AUC0–10h in TRL fractions was greater for 150 g CWE vs. 75 g CWE and no egg (79 ± 12a vs. 21 ± 12b vs. 13 ± 12b mg • dL−1 • 10h, p = 0.0005). Similarly, in study 2, total cholesterol AUC0–10h in TRL fractions was not different between 100 g CWE vs. no egg (5.2 ± 0.9 vs. 3.8 ± 0.9 mg • dL−1 • 10h, p = 0.30) but triacylglycerol AUC0–10h in TRL fractions was greater for 100 g CWE vs. no egg (31 ± 3a vs. 11 ± 3b mg • dL−1 • 10h, p < 0.0001). In both studies, plasma total cholesterol AUC0–10h was not affected by egg consumption (23 ± 13 vs. 20 ± 13 vs. 22 ± 13 mg • dL−1 • 10h, p = 0.92; 50 ± 11 vs. 43 ± 11 mg • dL−1 • 10h, p = 0.65), while triacylglycerol AUC0–10h was increased (207 ± 36 vs. 66 ± 36 vs. 66 ± 36 mg • dL−1 • 10h, p = 0.0097; 125 ± 23 vs. 50 ± 23 mg • dL−1 • 10h, p = 0.0257) when subjects consumed more eggs that contain greater amounts of dietary cholesterol and triacylglycerol.

Collectively, these findings support that the dietary cholesterol found in whole eggs was not well absorbed and did not affect plasma total cholesterol concentration, although whole egg contains high amount of dietary cholesterol. Thus, increased intake of dietary cholesterol from eggs may not indeed raise the blood cholesterol concentration.

Support or Funding Information

Support: American Egg Board‐Egg Nutrition Center; NIH UL1TR001108; Purdue Ingestive Behavior Research Center