The egg-specific HDL rise is isolated by the substitute group (same CRD background, no eggs) showing no HDL change - so the increment is attributable to the eggs, not the diet background alone (though the CRD itself raises HDL, making this a same-background comparison rather than egg-vs-low-fat control).
Methodology
Randomized trial in 28 overweight/obese men (age 40-70, BMI 25-37) on a 12-week carbohydrate-restricted diet (10-15% energy from carbohydrate), randomized to 3 whole eggs/day (640 mg/day additional dietary cholesterol; EGG) or an energy-matched egg substitute with 0 cholesterol (SUB). Subjects classified as hyper- vs hypo-absorbers of dietary cholesterol. (Depth-limited: publisher full text returned HTTP 403; extracted from the complete abstract, the step-2 summary, and corroborated numbers.)
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