Wonders of Whey

Whey protein supplements may help you cope better with stress.1

Increased brain serotonin levels improve the ability to cope with stress, while a decline in serotonin activity is associated with depression. Tryptophan is the amino acid that increases serotonin levels in the brain. Its transportation into the brain is dependent on other amino acids with a neutral charge. This influences tryptophan exchange via the ratio of tryptophan to the sum of other large neutral amino acids. A diet high in proteins that have high amounts of tryptophan may theoretically increase brain serotonin levels.

Research: Twenty-nine (29) highly stress-vulnerable subjects and 29 other subjects participated in a double blind, placebo controlled study where all subjects were exposed to various experimental stresses after the intake of a whey protein (lactalbumin) or a casein supplement. Changes in mood, skin conductance, cortisol levels and plasma tryptophan/amino acid ratios were all assessed before and after the stress tests.

The researchers chose to assess whey’s lactabumin protein fraction as it possesses one of the highest concentrations of tryptophan of any known protein. The scientists were interested to see if a protein supplement could induce favourable brain serotonin levels.

Whey protein supplement increased the plasma tryptophan/AA ratio by 48%. In the stress vulnerable subjects the whey protein decreased cortisol levels and reduced depressive feelings and improved their ability to cope with the tasks presented. Results obtained could only mean the whey protein supplement was able to increase brain serotonin levels. A protein supplement that is high in lactalbumin has a natural ability to increase brain serotonin levels that produce beneficial effects in every day situations.

Whey’s anti-cancer properties are twice as effective as soy.2

In an attempt to determine what protein possesses the best cancer fighting abilities, female rats were fed a diet containing either soy protein isolate, whey, or casein while the scientists attempted to induce tumors using the chemical 7,12-dimethylbenzanthracene. Also, the rats were mated with others fed the same protein to see if these protective effects could be passed on to the next generation. All rats grew well on these proteins. However, as the months went by, tumors developed in the casein and soy-fed rodents. The whey protein rats were virtually all clear. The whey and soy proved to be better than casein, while whey protein proved to be at least twice as effective as soy in reducing both tumor incidence and multiplicity. In many instances this protective effect of whey protein was able to be passed on to the second generation.

Lactoferrin (a whey protein fraction)
Was shown to inhibit colon carcinogenesis in male rats treated with another carcinogenic chemical azoxymethane.3 Most importantly these protective effects were demonstrated with easy to achieve, realistic amounts of the lactoferrin; about the same as contained in high quality whey oligopeptide formulations. Both a mere 2% and 0.2% of total protein intake proved highly effective in offering protection from the carcinogen.

Whey isolates are absorbed differently than other types of proteins.4

Researchers in Spain presented a rheokinetic study that examined the dynamic surface tension properties of whey isolate. Rheology and rheokinetics is the study of dispersion and flow of matter, in this case protein. Using constant temp (20o), pH (5) and ionic strength (0.05M) the results of the rheological parameters assessed show whey isolates possess different diffusion properties and interfacial unfolding actions to other proteins previously examined.

Whey isolate has the lowest plasmin levels.

Growth of bacteria is a real problem in the manufacturing of nonfat, dry milk products. It is shown to occur in casein and most whey protein products, even when kept at refrigeration temperatures. This bacteria causes an increase in plasmin activity. Plasmin is a native milk proteolytic enzyme that can break down the peptides that make whey proteins so effective. The food science researchers tested for plasmin activity in all types of whey. Acid whey showed the highest concentrations of plasmin, more than sweet whey. While some commercial whey protein concentrates also showed alarming degrees;16.3 to up to 330 mcg/g of protein. The significantly lowest levels by far were found in whey isolate (2.1 to 4.4mcg/g).

References:
[size=85] 1. Am.J.of Clin.Nutr.71(6):1536-1544,2000.
2. Cancer Epidemiol Biomarkers Prev. 9(1):113-7, 2000.
3. Mutat Res 462(2-3):227-33,2000.
4. J.Agric Food Chem. 47(6):2241-8,1999.
5. J.Dairy Sci. 83(3):387-94,2000.[/size]

Whey & Casein: Putting it together

When tucking into bed at night, you're about to embark on a six to eight hour journey of rest and repair. However, during this time you aren't feeding the body. We call this the post-absorptive period:

Throughout the day, the first hour or two after eating is referred to as the post-prandial period. During this time, the body digests and absorbs nutrients. When you eat and even during the post-prandial period, the body's maintenance needs for blood glucose and energy are met. At this time it begins to synthesize proteins and glycogen in the liver and muscle.

Once this period is over, the post-absorptive period sets in. After the absorption of the nutrients from your last meal is complete and the nutrients in the blood have been delivered, the body begins using those stored nutrients for energy. Then, in order to maintain blood glucose and tissue metabolism, the liver and muscle start metabolizing and sending glucose and amino acids out into the blood.

If you're eating frequently during the day, the overnight period is your longest post-absorptive period. It should be no surprise that after an overnight fast and a long post-absorptive period, some of the muscle glycogen and muscle protein will have been depleted. In fact, research has verified this hypothesis and shown specifically that after the overnight fast, muscle protein breakdown exceeds muscle protein synthesis. Interestingly, the opposite is true in the splanchnic region (gut, liver, etc) because in these tissues, synthesis exceeds breakdown. Therefore during the night, muscle is broken down to feed the gut/liver/etc and presumably other tissues as well (1).

Feeding For Increased Muscle Mass

Large increases in blood amino acid levels (100-200% above the fasted baseline) are necessary for increasing protein synthesis. Therefore a protein meal containing at least 20-30 grams of fast-digesting protein (like whey) can accomplish such a goal.

Interestingly, to inhibit protein breakdown we only need small increases in blood amino-acid levels (25-50% above fasted baseline). However, these small increases must be prolonged (4-5 hours) in order to realize this inhibition of protein breakdown. In this situation, a slow-digesting protein like casein is necessary.

Unfortunately, when large increases in blood amino acid levels (+100%) are achieved via intravenous infusion for a prolonged period of six hours, protein synthesis only increases from the 30 minute to the two-hour mark. After two hours, protein synthesis rates almost immediately return to baseline. Unbelievably, protein synthesis rates remain at baseline levels from the two hour to the six hour marks, even with the same level of hyperaminoacidemia (2).

Large bursts of hyperaminoacidemia every four hours or so (to stimulate synthesis in a phasic manner), coupled with a prolonged low-level hyperaminoacidemia (to chronically inhibit breakdown) may be the best way.

Consider the "pros" and "cons" of the bodybuilder's two main sources of protein:

• Whey protein intake (30g) produces large transient hyperaminoacidemia. After an hour, blood amino acids are elevated by about 300%. After two hours, about 92%. After four hours, you're back to baseline. This is ideal for increased protein synthesis but does nothing for protein breakdown (3,4).

• Casein protein intake (30g) produces moderate but prolonged hyperaminoacidemia. After two hours, blood amino acids are elevated by about 32% and after four hours by about 35%. After seven hours, blood amino acids are still elevated. This is ideal for prevention of protein breakdown but does nothing for protein synthesis (3,4).

Enter Milk
Milk protein is composed of 80% casein and 20% whey. Milk is interesting in that, believe it or not, the whey and casein fractions are absorbed separately. In one study, subjects consumed skimmed milk and were evaluated over the course of eight hours. With milk-protein ingestion, there's a rapid rise in blood amino acids within one hour (probably as a result of the whey fraction), a plateau from one to three hours (a combination of simultaneous whey and casein absorption), and then there's a progressive decline over the course of the next eight hours. However, blood amino acids are still elevated at the eight hour point as a result of the casein fraction. (5).

A combination of ingredients that promotes two large bursts of hyperaminoacidemia every four hours (leading to two bursts of synthesis — one at bedtime and one four hours later) and a prolonged low-level hyperaminoacidemia (to inhibit breakdown).

For the second burst of fast protein and hyperaminoacidemia that we want about four hours into our slumber. So the simplest way to do this would be to make a big shake/meal before bed, consume half at bedtime and the other half in the middle of the night.

To summarize this little bedtime story:

• About halfway through the night your body runs out of muscle-building fuel and leaves you in a catabolic state. To prevent this, it's a good idea to get some protein before bed.

• A better and more-affordable choice is plain old cottage cheese and/or a blend of proteins like those found in Low-Carb Grow!

[size=85]References
Written by John Berardi
1) Meek, SE, et al. Diabetes. 47(12): 1824-1835, 1998.
2) Bohe, J, et al. Journal of Physiology. 532(2): 575-579, 2001.
3) Dangin, M, et al. Am J Physiol Endocrinol Metab. 280:E340-E348, 2001.
4) Boirie, Y, et al. Proc Natl Acad Sci USA. 94:14930-14935, 1997.
5) Bos, C, et al. British Journal of Nutrition. 81, 221-226, 1999.[/size]