Saturday, March 03, 2007

Protein Series Part III: Whey Protein

Whey Protein, Impressive & Versatile
by Jose Antonio, Ph.D.
Melinda Mergen

Whey Protein proves itself to be a unique and impressive contender.

Whey is a unique (and impressive) protein in that it has shown to confer both performance-enhancing effects as well as an ability to help improve 'health' under selective clinical conditions.

It's one of the most widely consumed and studied proteins on the market. On the exercise side of things, Whey has been a long time favorite for many athletes.

In one study, researchers from McGill University in Montreal Canada gave 20 young adults (10 men, 10 women) a whey protein supplement, (10g twice daily) or a casein placebo for three months. Subjects were monitored for activity (via questionnaires).(1) The time spent in moderate (i.e. walking) and intense (i.e. running, cycling) exercise was calculated for each time period. Also, the percentage of awake-time spent being active was determined. They also performed before and after measures of lymphocyte glutathione levels; 30-second work capacity on a bicycle and percentage fat.

After 3 months of consuming their respective supplements, they found that the whey protein group was superior to the casein group in the following categories:

Percentage fat: -4.8% (whey), +5.1% (casein)
Peak cycling power: +13.3% (whey), +1.6% (casein)
30 second cycling work capacity: +12.7% (whey), +0.9% (casein)
Lymphocyte glutathione: +35.5% (whey), -0.9% (casein)
Time spent in activity: +13.7% (whey), +4.7% (casein)

So what does this all mean? Well, perhaps the most important change is the increase in lymphocyte glutathione activity, which is an indirect measure of tissue glutathione levels. This is important because glutathione, a compound produced from three amino acids (cysteine, glutamic acid, and glycine) is one of the most important anti-oxidants in our bodies. You'll find glutathione in the watery portion of the cell (known as the cytosol or cytoplasm) as opposed to vitamin E, which is in the fatty portion of each cell. So Whey protein increases cellular glutathione, which in turn improves the free-radical fighting ability of your body. This should theoretically improve muscle recovery and overall health. Thus, what may have happened is that the whey-protein, fed subjects may have felt better, and thus were more active, and could consequently recover more quickly from activity or exercise. This would in turn lead to better exercise performance and decreased, percentage fat. So did the whey protein itself improve exercise performance and body composition? Or was it an indirect effect in that it helped promote expeditious recovery and overall health? From a lean body mass accruement standpoint, keep in mind that there are other studies which suggest that casein may be better. However, another unique aspect of whey is its effect on the immune system. For instance, supplementation with whey proteins persistently increased plasma glutathione levels in patients with advanced HIV-infection.(2) And in a prospective double-blind clinical trial in 18 HIV-infected children (1.98-6.37 years), whey protein, concentrate supplementation stimulated glutathione synthesis and, possibly, decreased the occurrence of associated co-infections.(3)

Whey is a pretty impressive source of protein. In addition to application in sports, there's some pretty impressive evidence that it can help various clinical conditions.

Additional Reading and Information

Whey protein on plasma glutathione levels.

Whey protein affects muscular performance.

Please click here for References and additional Reading Material.



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