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.
I’m not too concerned with it, personally. We already know that regular egg consumption has a net positive effect on blood lipids , including levels of highly oxidative small, dense LDL. We also know that whey protein supplementation decreases VLDL , at least in rats, and that lactoferrin, a whey protein concentrate component, appears to reduce LDL oxidation . Even if you’re consuming a modicum of oxidized dietary cholesterol from the occasional scoop of whey protein power, the benefits – including increased lean mass, better recovery from strength training, as well as a reduction in atherogenic lipids – seem to outweigh any potential negatives. Additionally, when we consume oxidized cholesterol in the bioreactor that is the stomach (at a very low pH) we may also be mitigating some of the potential harmful effects of oxidized cholesterol.
Is grass-fed whey protein worth the extra cost?
I don’t think so. If ethical concerns are your primary reasons for eating grass-fed beef and dairy, it might make sense to shell out the extra dough for grass-fed whey powder, but if you’re drawn to it for the health benefits, don’t bother. There really aren’t any. Think about why we prefer pastured animal products in the first place – favorable fatty acid profiles, more fat-soluble vitamins, cleaner, better-tasting meat (once you get used to beef tasting like beef). Why do we take protein powder? For the protein. We aren’t expecting incredible flavor, vast amounts of vitamins, or healthy fats; we just want some fast-acting protein. Feel free to use grass-fed whey protein, but don’t think it’s doing anything special. You’re better off buying grass-fed meat (and dairy) instead.
When’s the best time to take whey protein, if I’m looking for increased protein synthesis and muscle recovery?
I generally don’t worry about meal timing  too much, but if you do, take your whey protein within a half hour post-workout. Your muscles will be insulin sensitive and primed for nutrients and glycogen, so the insulinogenic release from the whey will be a boon.
Of course, whey isn’t the only protein powder around. It’s my personal favorite for a few reasons (the anti-atherogenic qualities, the fast absorption, the positive effects on lean mass development), but a number of you asked about other sources, so here’s some info on a few of the more popular varieties, including their respective biological values (BV).
The BV is one way to measure a protein’s “usability.” The higher the BV, the greater the proportion of available protein that can be synthesized by the body’s cells. Higher BVs also indicate a greater amount of essential amino acids – those amino acids that the body cannot synthesize or convert on its own and must instead obtain from the diet. Whey protein concentrate, for example, has a biological value of 104, while isolate has a BV of 100. Milk itself? 91. Beef? 80. You want a high biological value in your powders especially, since their only reason for existing is to provide a quick, easy influx of dietary protein. Interestingly, BV goes down with greater protein intake. Whey’s BV of 104 is at intakes of 0.2g/kg; it drops to around 70 at 0.5g/kg. While this isn’t really an issue for a PBer who uses shakes sparingly as supplements and gets most of his or her protein from whole foods, it might dissuade one from getting all their protein from powder.
Note, though, that biological value does not refer to the amount of protein in the powder; it only refers to the usability of the protein in the powder. A particular powder might be 60% protein, and the biological value would tell you exactly how much of that 60% is usable by the body. Different powders have different protein contents. Hemp protein, for example, is often about 50% protein, but it varies by the manufacturer. A quick glance at the nutrition facts should clue you in.
There’s also the protein digestibility-corrected amino acid score (PDCAAS ), which is the method by which the World Health Organization evaluates protein value. It’s a newer model, and it’s based on the amino acid requirements of humans, specifically children. Most protein powders (and their consumers) stick with the BV, but the PDCAAS is gaining in popularity. Whey protein (both isolate and concentrate) has an optimum PDCAAS of 1.
BV – 77
PDCAAS – 1
Derived from that other variety of milk protein, casein protein powder doesn’t absorb as quickly as whey. It’s a complete protein with the full range of amino acids (including ample amounts of glutamine, which transports nitrogen to tissue), just like whey, but it’s potentially far more problematic because of the autoimmune/allergen issue. Those with dairy allergies should probably avoid it. Bodybuilders swear by casein; they dig it for the slow absorption rate and tend to take it before bedtime. One (industry funded) study found  that casein was inferior to whey protein in terms of body composition  and muscular strength outcomes, so I wouldn’t replace whey with casein just yet. There may be some benefit to taking both, though, seeing as how both casein and whey are a package deal in nature. Milk is certainly a popular post-workout recovery drink, and it contains both casein and whey.
Egg White Protein
BV – 100
PDCAAS – 1
Egg white protein powder is another highly bioavailable protein choice. In fact, it’s so bioavailable that it represents the BV against which all others are compared (that’s why whey can have a BV exceeding 100). All the amino acids are represented. If you’re concerned about oxidized cholesterol, stay away from whole egg protein powder. You may be able to get a hold of a minimally processed whole egg powder with very little oxidation, but you’ll probably end up spending a ton of money. Just eat actual eggs or stick with egg white powder instead. The Paleo Diet blog recommends egg white protein powder for those with autoimmune disease, but it’s worth noting that egg whites themselves can be rather potent allergens, so use caution.
BV – 65
PDCAAS – 0.69
I’m generally down on vegetarian protein powders. In my experience, they just don’t work as well as the animal-based ones. We’re not meant to get all our protein from vegetable sources, and our absorption of vegetable-based protein isn’t as efficient, so you have to consume far more pea protein powder just to get enough – and this stuff can get pretty pricey. No protein powder is perfectly Primal, but pea protein powder is even less so. If egg and milk protein powders are off limits for whatever reason, though, give pea protein a shot.
BV – 83
PDCAAS – 0.47
Rice protein powder is created by isolating the protein from the brown rice grain. Rice is already one of the least offensive grains out there, so a smattering of rice-based amino acids will work okay. You’re not going to absorb or digest the rice protein with as much ease as with animal-based protein, but that’s fine. A reader mentioned that any form of dairy protein powder resulted in great discomfort; if that’s true, rice protein powder may be a good choice.
I was unable to get a reliable score, but the general consensus was “lower BV” than other powders.
PDCAAS – 0.46
Hemp is another option for vegetarians (or nutrition explorers). Like the other vegetarian protein powders, hemp is quite a bit lower in protein content than the animal protein-based powders (or even other vegetarian powders). It’s generally loaded with tons of fiber and a bit more fat than other powders, but fiber-free versions do exist. Again, not my first choice, and it’s fairly expensive, but hemp powder does taste relatively good.
A good rule is to choose protein powders that have both high BVs and high PDCAASs.
Do You Need Protein Powder?
Whey protein powder is proven to be effective, and it’s ubiquitous and inexpensive. Protein powder in general can help athletes recover from training, and it doesn’t have to be dairy-based, if you’re sensitive. There’s nothing wrong with dabbling (or even throwing yourself into) in alternative protein powders, and in the case of casein and egg whites, you might even see added benefits by incorporating them into your whey regimen.
But that doesn’t mean you need protein powder.
Take your time and evaluate your diet. You may find that you don’t need powder supplements. I certainly don’t need any myself, but that doesn’t mean I don’t enjoy a big whey shake after an intense workout session from time to time, just for the anabolic effects if not for the convenience and taste. If you’re not getting enough protein, or you can’t find the time to cook every single meal, try some protein powder. Otherwise, eat a steak .