Natural sources of Casein protein

Last week’s whey protein post generated a ton of great questions. I’m going to try to get to as many as I can today, and I’ll include information on alternative protein powders at the end. As always, let me know if I miss anything and I’ll try to rectify that in the future.

What about oxidized cholesterol? Aren’t most whey protein concentrates exposed to significant amounts of heating that oxidizes the cholesterol?

Oxidized cholesterol is potentially dangerous. In fact, along with Ancel Keys’ fudging of the saturated fat intake data, it was the oxidized cholesterol-fed rabbit model that jumpstarted the crusade against fat and cholesterol. Undamaged dietary cholesterol wasn’t atherosclerotic; oxidized dietary cholesterol was the stuff that contributed to arterial plaque (feeding pure cholesterol to an obligate herbivore played a part, too) in the rabbit.

Depending on how whey protein concentrate is processed, some of its cholesterol is oxidized. The higher the temperature used, the greater the oxidation. Sounds horrible, right? Not so fast. The average serving of whey protein concentrate contains 30 mg of cholesterol. Let’s assume every last milligram of that is oxidized – sounds pretty terrible, right? Maybe not. Consider the average egg, which contains 220 mg of cholesterol. If you scramble that egg, breaking the yolk and exposing it to oxygen and heat, a significant portion of the cholesterol may be oxidized. I don’t know about you, but I’ve been known to put away half a dozen eggs in a single sitting. Granted, I usually fry mine in butter and try to preserve the structure of the yolk (partly because it tastes better, and partly to dip my bacon), but I’d wager that anyone who eats cooked eggs on a regular basis eats some small amount of oxidized cholesterol, too. Even if just a tiny fraction of that 220 mg/egg cholesterol is oxidized, it’s comparable to the amount you’re getting from a whey protein shake every now and then.