Vitamins, Minerals and Dietary Supplements
What is valine? Why do we need it?
Valine is an essential amino acid. It belongs to a special
group of amino acids called branched-chain amino acids (BCAAs),
which are needed to help maintain and repair muscle tissue.
Valine also helps prevent muscle proteins from breaking down
during exercise.
While there is still some question as to whether valine and
other branched-chain amino acids improve exercise performance
or enhance the effects of physical training, supplements may
be beneficial under certain conditions. Some studies have
shown that valine and other BCAAs prevent muscle loss at high
altitudes and may prolong physical endurance under extreme
heat. People with liver and kidney failure may also benefit
from valine supplementation. In addition, a trial published
in 1988 found that BCAA supplements help patients with Lou
Gehrig's disease maintain muscle strength; other studies
have refuted these findings, however.
How much valine should I take?
The recommendad daily dosage of valine and other branched-chain
amino acids is 25-65mg per pound of body weight. Most diets
provide an adequate amount of BCAAs. Competitive athletes
sometimes take larger amounts up to four grams of valine
(and 11 grams of BCAAs overall) per day.
What are some good sources of valine?
What forms are available?
All protein-containing foods have some amount of valine/BCAAs.
The best sources include red meat and dairy products such
as eggs, milk and cheese. Whey protein and egg protein supplements
are other good sources. Valine is usually sold in conjunction
with other amino acids.
What can happen if I don't get enough
valine? What can happen if I take too much? Are there any
side-effects I should be aware of?
Only individuals who are deficient in protein would become
deficient in valine. However, since most Western diets provide
more than enough protein, valine deficiency is extremely rare.
High intake of valine and other BCAAs could cause these substances
to be converted into other amino acids (or to fat for storage).
Individuals with kidney or liver disease should not consume
large amounts of valine or other BCAAs without first contacting
a qualified health care practitioner.
At the time of this writing, there are no known drug interactions
with valine.
References
- Blomstrand E, Ek S, Newsholme EA. Influence
of ingesting a solution of branched-chain amino acids on
plasma and muscle concentrations of amino acids during prolonged
submaximal exercise. Nutrition 1996;12:48590.
- Freyssenet D, Berthon P, Denis C, et al.
Effect of a 6-week endurance training programme and branched-chain
amino acid supplementation on histomorphometric characteristics
of aged human muscle. Arch Physiol Biochem 1996;104:15762.
- Kelly GS. Sports nutrition: A review of
selected nutritional supplements for bodybuilders and strength
athletes. Med Rev 1997;2:184201.
- Tandan R, Bromberg MB, Forshew D, et al.
A controlled trial of amino acid therapy in amyotrophic
lateral sclerosis: I. Clinical, functional, and maximum
isometric torque data. Neurology 1996;47:12206.
- Van Hall G, Raaymakers JSH, Saris WHM,
Wagenmakers AJM. Supplementation with branched-chain amino
acids (BCAA) and tryptophan has no effect on performance
during prolonged exercise. Clin Sci 1994;87:52.