Whey or Casein? Which Would be the Better "Staple" Protein Source for Your Trip to Desert Island?

Image 1: They are both sourced from cow's milk, but which is the better part? Whey, the byproduct of cheese production, or casein the cheese protein, itself? A recent study would suggest that it's the "waste product" you would have to chose if you could only have one.

"Whey is the way to go!" I suppose even I have had a headline like that in one or even several of the daily news items, here at the SuppVersity - and rightly, so! With it's high content of branched-chain amino acids (BCAAs) this fast-digesting protein source is certainly the #1 choice for anyone whose goal is to build lean muscle tissue. Whey's slow-digesting brother casein, on the other hand, is often hailed as the "muscle-preservative", the 24h-protein source that will prevent muscle catabolism, when for whatever outrageous reason (like sleep, for example) you cannot ingest your bi-hourly protein shake... well, I guess those of you who have been following the Intermittent Thoughts on Intermittent Fasting will already be "rolling on the floor laughing", but hey! Do we really know whether casein or whey would be the better "staple" protein - I mean, if you sipped it throughout the day?

Casein vs. whey - which one to chose if you cannot have both?

While I would not say that one study could provide a definite answer to this question, the results of a recently published paper by Stéphane Walrand et al. (Walrand. 2011) provides further evidence that whey, not casein would be your best choice - regardless of the diminished return that comes with sipping it.

Figure 1: Ingredients of the 6 diets the rats in the Walrand study were fed for 5 months; CAS = casein, WHEY = whey (data adapted from Walrand. 2011)

In their long-term (5 months!) feeding study, the scientists supplied 21 week old male Winstar rats (at the beginning of the study the animals were thus "middle-aged") with one out of 6 experimental diets (cf. figure 1). The composition of the diets differed not only in their total energy and protein content (ad libitum = 440kj/day; energy restricted only 60%, i.e. 264kj/day), but also with regard to the protein content and source (casein vs. whey). In that, it is particularly noteworthy is that the "energy restricted" diet was actually a "high protein" diet. After all, the protein content of the latter was identical to the one of the rats that had free access to  (the group that was "only" energy restricted received was matched to the average protein consumption of the ad-libitum fed rats.

Figure 2: Effect of 5 months of the experimental diets on muscle and fat weight of male Wistar rats (data adapted from Walrand. 2011)

Contrary, to what you may have expected, the "protein deficient" protein & energy restricted diet did yet not lead to profound losses of lean muscle tissue (cf. figure 2). On the contrary, the protein & energy restricted group that received whey protein as their exclusive protein source had 5% and 2% greater soleus and tibialis anterior mass than the ones that received the "high protein" energy restricted diet. Before you start questioning the value of "high" protein intakes when dieting, you should yet better take a look at the impact of the "high" protein content of the non-protein-restricted diet had on the diet induced reductions of the abdominal fat mass. I mean -87% reduced abdominal fat in the energy & protein reduced group is impressive, the neigh complete annihilation of the abdominal fat (-93%) in the non-protein restricted group, on the other hand, is mind-boggling.

Figure 3: Effect of 5 months of the experimental diets on muscle and fat weight of male Wistar rats (data adapted from Walrand. 2011)

If we also consider the nitrogen balance and the absolute rates of muscle protein synthesis (cf. figure 3), it also becomes evident why the rats on the protein & energy reduced diets retained slightly more lean mass (+3%), when they were fed whey protein, instead of casein. The rats who received whey as their main protein source simply had a favorable nitrogen balance and increased muscle protein synthesis.

Image 2: Sardines for diabetes prevention!?

Before you now throw away your eggs, your cheese, your beef and whatever else, I want to briefly introduce you to the results of two other recently published studies, which would indicate that rotating in some sardines or sheep meat could produce even more favorable results than living on whey alone. While Madani et al. found that sardine protein ameliorated fructose-induced hyperglycemia, insulin resistance, hyperlipidemia and inflammation (vs. casein) in a 2-months rodent study (Madani. 2011), Feng et al. report that the consumption of sheep meat instead of casein lead to increases in free T3 (thyroid hormone) and statistically significant increases in energy expenditure in Sprague-Dawley rats that were fed otherwise identical diets (Feng. 2011).

Despite these and the results of previous studies, most of which would suggest that if you had to chose just one protein source, whey or casein, whey should be the protein of choice, I hope that I do not have to tell you, as a diligent student of the SuppVersity that imbalances are the root cause of many, if not most modern diseases. So, getting all your protein from whey and nothing but whey should not be something you should even remotely take into consideration. And in case you forgot about that: Milk has both of them and a ton of other vital nutrients ;-)

Want B12, But Hate Meat? Drink Milk! SNAC-Fortified Cyanocobalamin 136% More Bioavailable Than Standard B12 - Still Less Effective Than B12 From Cow's Milk

Figure 1: Milk still rules the
world (of B12 supplements ;-)

Vitamin B12 deficiency is probably more prevalent, than many people would have it. The water-soluble vitamin is most abundant in foods of animal origin and vegetarians (let alone vegans) are as much at risk of having inadequate B12 levels, as people with achlorhydria and, consequently, low intrinsic factor (an enzyme that requires an acidic environment to function and facilitate the utilization of B12 from foodstuff), or more generalized disturbances of the gastrointestinal structure due to aging (food-cobalamin malabsorption becomes increasingly prevalent after the age of 50), gastric resection, ileal resection, Crohn's disease, and bacterial overgrowth of the intestine. With vitamin B12 deficiency affecting cell division and precipitating to megaloblastic anaemia and neuropathy, close monitoring not only of vitamin B12 intake, but also of its proper utilization is of utmost importance for people belonging to one of the aforementioned groups.

Scientists from Emisphere Technologies in Cedar Knolls, New Jersey, have now come up with a new cyanocobalamin/SNAC coformulation, in which the sodium caprylic acid salt, N-[8-(2-hydroxybenzoyl)amino]caprylate (SNAC), a proven drug delivery agent, shall facilitate a more pronounced and more reliable absorption of orally supplemented vitamin B12 (Castelli. 2011). The formula, which contained 5-mg cyanocobalamin and 100-mg SNAC was administered to 6 human subjects in the fasted state in the form of 1 tablet, which had to be taken with 50 mL of water. Blood samples were taken at staggered intervals with the last blood draw taking place 24h after the ingestion of the B12/SNAC coformulation.

Figure 1: Time to and maximal serum concentration of B12 after oral administration or infusion of cyanocobalamine with and without SNAC; note: in order to compensate for the major differences between oral cyonocobalamine with and without SNAC a logarithmic scale was used (data adapted from Castelli. 2011).

As expected the concomitant administration of sodium N-[8-(2-hydroxybenzoyl)amino]caprylate (SNAC) increased the meager biovalability of cyanocobalamine (which is absorbed really poorly, anyway) significantly:

Absolute bioavailability of B12 with the SNAC formulation was calculated from non–baseline-adjusted data to be 5.09% and was significantly greater (P < 0.05) than the commercial formulation (2.16%).

In view of the recently elucidated bioavailability of natural B12 from plain cow's milk (Matte. 2011), or should I say "liquid white gold", the 136% increase in bioavailability Christina Castelli and her coworkers achieved with their artificial combination of B12+SNAC appear quite ludicrous. 8%-10% that is the bioavailability et al. report in Jacques Matte and his colleagues from Canada report in their study on the bioavailability of vitamin B12 from cow's milk. Granted, this is a pig model, but other than rodents, which are usually used when it comes to studies, in which surgical interventions are necessary to elucidate the exact pharmacodynamics of a specific drug, pigs provide a very adequate model for the human gastrointestinal system, or as Miller and Ullrey already stated it in a 1987 paper on the "The Pig as an Animal Model For Human Nutrition" (Miller. 1987)

[...]with the possible exception of nonhuman primates, it is apparent that the omnivorous pig is one of the best models for study of nutrition issues in the omnivorous human.

This long established adequacy of the pig model of the human gastrointestinal tract has only recently been confirmed by Goulloteau et al. (Guilloteau. 2010). Matte et al.'s result that vitamin B12, which is naturally and abundantly present in cows’ milk, is more available at the intestinal level than the synthetic form - even if the latter is supplemented with SNAC - are thus very likely to apply to humans, as well.

Figure 2: Pharmacokinetics of vitamin B12 from different sources measured in pigs with an ultrasonic flow probe around the portal vein and a catheter inside the portal vein; values expressed as differences vs. unsupplemented animals; both values for cyanocobalamine alone are effectively 0, i.e not different from unsupplemented pigs (data adapted from Matte. 2011).

These results are also in accordance with retrospective studies in human subjects showing that vitamin B12 status is highly correlated with dairy product intake and studies on the absorption (absorption = entering the cells vs. bioavailability = becoming available in the blood stream) of vitamin B12 from dairy products in older men and women (>60y) by Robert M. Russel et al. (Russel. 2001), who report absorption of up to 65% for milk, which would be almost identical to the generally accepted absorption coefficient for meat products.

Note: Using a pig model Matte et al. were able to actually measure the portal-drained viscera (PDV) flux of vitamin B12, which provides more reliable results than radio-labelling studies, as they were used in Russel et al. It is thus all the more intriguing that the PDV for the unsupplemented diet or cyanocobalamin supplements [...] were not different from 0", or in other words - providing pigs with cyanocobalamine, which is the form of vitamin B12 that is used in most common dietary supplements, had no effect  on serum B12 concentrations, at all.

So, what does this tell you, after all? Well, let me phase it like that: If you have a Ferrari Enzo (milk and meat) waiting for you at the front door (in the fridge), wouldn't it be plain-out stupid to try to chip-tune (add SNAC) the family car (cyanocobalamine)? An the moral of the Story? Eat, don't supplement your vitamins!