Scientist Develops Protein Supplement as Possible Muscle-Builder
WASHINGTON (AP) _ A dietary supplement originally developed to help grow leaner cattle now may help athletes get fitter faster.
Everybody who eats protein naturally produces the chemical HMB in their bodies, but Iowa State University scientists discovered how to bottle the substance. Large doses helped male athletes build twice as much muscle as exercise alone, according to research presented to biologists meeting in Washington Monday.
``If you take HMB and a bag of potato chips and sit on a couch, you’re not going to see any effects,″ cautioned Iowa State veterinarian Steven Nissen.
But combined with exercise, 3 grams of HMB a day _ the amount derived if anyone could stand eating 500 grams of meat (about four hefty hamburgers) _ helped men develop more muscle and lose more fat, he said.
Nissen acknowledges there are still lots of unanswered questions about HMB’s effects, but a company the university started to manufacture HMB already is selling it fast. The supplement’s distributor even claims to have sold HMB to some Olympians and professional football players.
Researchers have long touted high-protein diets for athletes, and specifically a protein amino acid called leucine. HMB is a metabolite of leucine, the one Nissen believes causes leucine’s muscle-building effects. A metabolite is a substance produced by or taking part in metabolism.
``We’re becoming more sophisticated″ in searching for muscle-building aids, said Elizabeth Applegate, an expert on dietary fads at the University of California, Davis, who had not yet seen Nissen’s results.
``First we eat meat, then we take amino acids, now we’re taking metabolites of amino acids.″
HMB appears safe, but needs some more research to prove how it affects muscle, added Rick Sharp, sports medicine director for the U.S. Olympic swimming team, who is following Nissen’s research to determine whether to recommend that his athletes take HMB.
The Olympics and other athletic events ban the use of numerous drugs, including muscle-building steroids, but typically do not regulate nutritional supplements that are sold legally and appear to pose no health threat.
Nissen discovered HMB, known chemically as beta-hydroxy methylbutyrate, in 1988 while searching for ways to grow leaner cattle.
A colleague at Vanderbilt University did the first human testing in 1991, finding 10 regular exercisers who took HMB built more muscle than 10 others who took dummy pills.
Then Nissen began demonstrating the results weren’t a fluke.
He unveiled his fifth and largest clinical trial Monday. Forty men ate 3 grams of HMB a day or a placebo while undergoing strenuous exercise for four weeks. The HMB takers increased muscle by 3.1 percent and lost 7.3 percent of body fat, while those on placebo built only 1.9 percent muscle and lost 2.2 percent fat.
He’s now studying HMB in women.
Nissen isn’t sure how HMB works, but it may affect an oddity of exercise: Exercise builds new muscle but simultaneously can break down existing muscle.
Getting the benefit and not the breakdown is ``a very fine balance,″ said the Olympic swim team’s Sharp, who wants to study whether HMB could help swimmers and other Olympic athletes during their intensive training.
Meanwhile, some 30,000 people have ordered HMB since October, including Dallas Cowboys and Denver Broncos football players and members of the Canadian Olympic bobsled team, said Bill Phillips, president of EAS Experimental and Applied Sciences in Denver, which markets HMB.
Human dietary supplements are not federally regulated before their sale, but Nissen hopes to seek Food and Drug Administration approval within 18 months to sell HMB as a nutritional aid for cattle _ as soon as he produces enough to drop the $100 per pound price to one farmers can afford.
And he’s about to study HMB as a medicine, giving it to people in nursing homes to see if it counters the loss of muscle that comes with age and such diseases as cancer.