Before the dietary intervention began, the participants underwent a 2-wk washout period, during which 0 eggs/d were consumed. This baseline period was followed up by sequentially increasing intake of 1, 2, and then 3 eggs/d (large, grade A, white purchased at local supermarkets) for 4 wk each; and before you ask: no they were not told to either hard-boil, soft-boil, fry or scramble them.
|Figure 1: Overview of the intake sequence (DiMarco. 2017).|
|Figure 1: LDL and HDL particle sizes; note: to make the figure more legible and the ratios easier to recognize, I converted the LDL values to nmol/dL (that's 1/10 of nmol/L as it is still used for HDL | diMarco. 2017)|Figure 2: The antioxidant concentration in the subject's plasma increased linearly w/ every egg.
- improved levels cholesterol efflux and HDL transport due to higher plasma apoAI (9–15% efflux) and lecithin-cholesterol acyltransferase aka LCAT activity (5–15% transport),
- increased antioxidant defenses as can be seen in the 11% increase in apoAII (P < 0.05), the anti-oxidant, cardioprotective cousin of apoAI, and a 20–31% increase in plasma lutein and zeaxanthin (P < 0.05, see Figure 2)
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|Figure 3: Just as in previous studies, there was a correlation between increased ApoA-I concentrations (DiMarco. 2017) and the number of large HDL particles - both have been associated w/ reduced heart disease risk.|
Is the fact that the study was funded by the Egg Nutrition Center bad news? Probably not, after all, it is very unlikely that the scientists would have gotten public funding for a study in (a) healthy subjects that (b) served its subjects three eggs a day, not per week as it has been done in most of the previous experiments. Plus: Their conclusion, which is where you will usually find evidence of a bias if there is one, is neither exaggerating nor misrepresenting their findings: "Overall, intake of ≲3 eggs/d favored a less atherogenic LDL particle profile, improved HDL function, and increased plasma antioxidants in young, healthy adults" (DiMarco. 2017).
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