Also indexed as: Protein [Whey]
What is it?
Whey protein is a mixture of some of the proteins naturally found in milk. The major
proteins found in whey protein include beta-lactoglobulin and alpha-lactalbumin. Whey protein
has one of the highest protein digestibility-corrected amino acid scores (PDCAAS; a measure of
protein bioavailability) and is more rapidly digested than other proteins, such as casein
(another milk protein). 1
Alpha-lactalbumin is a whey protein high in the amino acid tryptophan, which the body uses to make the
neurotransmitter serotonin. A double-blind study found that supplementing the diet with
alpha-lactalbumin helped improve scores on a memory test in people who were vulnerable to
experiencing problems with stress.2 The researchers speculated that the
alpha-lactalbumin raised brain serotonin levels in these subjects, which may have improved
their tolerance to stress.
Where is it found?
During the process of making milk into cheese, whey protein is separated from the milk.
This whey protein is then incorporated into ice cream, bread, tinned soup, infant formulas,
and other food products. Supplements containing whey protein are also available.
Whey protein has been used
in connection with the following conditions (refer to the individual
health concern for complete information):
Who is likely to be deficient?
People who do not include dairy foods in their diets do not consume whey protein. However,
the amino acids in whey protein are available from other sources, and a deficiency of these
amino acids is unlikely.
People who do not include dairy foods in their diets do not consume whey protein. However,
the amino acids in whey protein are available
from other sources, and a deficiency of these amino acids is unlikely. In fact, most Americans
consume too much, rather than too little, protein.
How much is usually taken?
Some benefits of whey protein have been demonstrated with as little as 20 grams per day.
For athletes in training a commonly used
amount is 25 grams of whey protein per day, and shouldn’t exceed 1.2 grams per 2.2
pounds body weight. Most clinical research has used similar amounts of whey protein.
Are there any side effects or interactions?
People who are allergic to dairy products
could react to whey protein and should, therefore, avoid it.3 As with protein in
general, long-term, excessive intake may be associated with deteriorating kidney function and
possibly osteoporosis. However, neither kidney
nor bone problems have been directly associated with consumption of whey protein, and the
other dietary sources of protein typically contribute more protein to the diet than does whey
protein. The possibility that certain proteins in milk may contribute to the development of
diabetes in children is controversial. But since whey proteins include some of the same milk
proteins, people who are avoiding milk because of concerns about the risk of diabetes should
not consume whey protein either.
At the time of writing, there were no well-known drug interactions
with whey protein.
References
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1. Dangin M, Boirie Y, Guillet C, Beaufrere B. Influence of the protein
digestion rate on protein turnover in young and elderly subjects. J Nutr
2002;132:3228S–33S [review].
2. Markus CR, Olivier B, de Haan EH. Whey protein rich in
alpha-lactalbumin increases the ratio of plasma tryptophan to the sum of the other large
neutral amino acids and improves cognitive performance in stress-vulnerable subjects. Am J
Clin Nutr 2002;75:1051–6.
3. Wal JM. Cow's milk proteins/allergens. Ann Allergy Asthma Immunol
2002;89(6 Suppl 1):3–10.
Copyright © 2006 Healthnotes, Inc. All rights reserved.
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The information presented in Healthnotes is for informational purposes
only. It is based on scientific studies (human, animal, or in vitro), clinical
experience, or traditional usage as cited in each article. The results reported may not
necessarily occur in all individuals. For many of the conditions discussed, treatment with
prescription or over the counter medication is also available. Consult your doctor,
practitioner, and/or chemist for any health problem and before using any supplements or before
making any changes in prescribed medications. Information expires March 2007.