"Long before it's in the papers"
November 01, 2011

RETURN TO THE WORLD SCIENCE HOME PAGE

Wine ingredient may help men cheat some of obesity’s effects

Nov. 1, 2011
Courtesy of Cell Press 
and World Science staff

When obese men take a fairly small dose of the red wine in­gre­di­ent res­ver­a­trol eve­ry day for a month, their me­tab­o­lisms im­prove, a study has found.

The sub­stance had al­so been found to in­crease life­span in some an­i­mal mod­els, but the ju­ry is out on wheth­er it has com­pa­ra­ble ef­fects in peo­ple.

In obese men, its met­a­bol­ic ef­fects ap­pear to be as good as those of se­vere cal­o­rie re­stric­tion, a sharp cut­back in eat­ing al­so as­so­ci­at­ed with in­creased life­span, the re­search­ers said. “We saw a lot of small ef­fects, but con­sist­ently point­ing in a good di­rec­tion of im­proved met­a­bol­ic health” with res­ver­a­trol, said Pat­rick Schrauwen of Maas­tricht Uni­vers­ity in The Neth­er­lands.

The find­ings, pub­lished in the No­vem­ber is­sue of the jour­nal Cell Me­tab­o­lism, are billed as the first to re­port the clin­i­cal ef­fects of the in­creas­ingly trendy sup­ple­ment.

Ear­li­er stud­ies in an­i­mals had shown that res­ver­a­trol pro­tects against the ill ef­fects of a fat­ty di­et and the symp­toms of di­a­be­tes, Schrauwen said. Still, no stud­ies had sys­tem­at­ic­ally ex­am­ined the met­a­bol­ic ef­fects of res­ver­a­trol in hu­mans. To fill that gap, the re­search­ers gave 11 obese but oth­er­wise healthy men a di­etary sup­ple­ment con­tain­ing 150 mil­ligrams of a 99 per­cent pure res­ver­a­trol (trade name resVida) for 30 days while they meas­ured the amount of en­er­gy they ex­pended, the amount of fat they were stor­ing and burn­ing, and more.

The da­ta show that, like cal­o­rie re­stric­tion, res­ver­a­trol sup­ple­ments low­er en­er­gy ex­pend­i­ture and im­prove meas­ures of me­tab­o­lism and over­all health, Schrauwen and col­leagues said. Those changes in­clude a low­er met­a­bol­ic rate, less fat in the liv­er, low­er blood sug­ar lev­els and a drop in blood pres­sure. Tri­al par­ti­ci­pants al­so ex­pe­ri­enced changes in the way their mus­cles burned fat.

“The im­me­di­ate re­duc­tion in sleep met­a­bol­ic rate was par­tic­u­larly strik­ing,” Schrauwen said. In the case of obes­ity, it’s not to­tally clear wheth­er burn­ing few­er cal­o­ries is a good or a bad thing, he added, but the findings do sug­gest that par­ti­ci­pants’ cells were op­er­at­ing more ef­fi­cient­ly, as they do fol­low­ing cal­o­rie re­stric­tion.

Those met­a­bol­ic ef­fects of res­ver­a­trol al­so came with no ap­par­ent side ef­fects, ac­cord­ing to the re­port.

Schrauwen said they chose to study obese people giv­en their in­creased risk for type 2 di­a­be­tes. In fu­ture stud­ies, he hopes to ex­plore the ef­fects of res­ver­a­trol in peo­ple who have al­ready pro­gressed to di­a­be­tes. Res­ver­a­trol sup­ple­ments are widely avail­a­ble, but more work is needed to es­tab­lish wheth­er they in­deed have the po­ten­tial to over­come the met­a­bol­ic aberra­t­ions as­so­ci­at­ed with obes­ity and ag­ing, ac­cord­ing to the re­search­ers. “I don’t see a rea­son for par­tic­u­lar cau­tion, but we do need long-term stud­ies,” Schrauwen said.

* * *

When obese men take a fairly small dose of the red wine ingredient resveratrol every day for a month, their metabolisms improve, a study has found. The substance had also been found to increase lifespan in some animal models, but the jury is out on whether it has comparable effects in people. In obese men, its metabolic effects appear to be as good as those of severe calorie restriction, a sharp cutback in eating also associated with increased lifespan, the researchers said. “We saw a lot of small effects, but consistently pointing in a good direction of improved metabolic health” with resveratrol, said Patrick Schrauwen of Maastricht University in The Netherlands. The findings, published in the November issue of the Cell Press journal Cell Metabolism, are billed as the first to report the clinical effects of the increasingly trendy supplement. Earlier studies in animals had shown that resveratrol protects against the ill effects of a fatty diet and the symptoms of diabetes, Schrauwen said. Still, no studies had systematically examined the metabolic effects of resveratrol in humans. To fill that gap, the researchers gave 11 obese but otherwise healthy men a dietary supplement containing 150 milligrams of a 99 percent pure resveratrol (trade name resVida) for 30 days while they measured the amount of energy they expended, the amount of fat they were storing and burning, and more. The data show that, like calorie restriction, resveratrol supplements lower energy expenditure and improve measures of metabolism and overall health, Schrauwen and colleagues said. Those changes include a lower metabolic rate, less fat in the liver, lower blood sugar levels and a drop in blood pressure. Trial participants also experienced changes in the way their muscles burned fat. “The immediate reduction in sleep metabolic rate was particularly striking,” Schrauwen said. Of course, in the case of obesity, it’s not totally clear whether burning fewer calories is a good or a bad thing. It does suggest that participants’ cells were operating more efficiently, as they do following calorie restriction, he explained. Those metabolic effects of resveratrol also came with no apparent side effects, according to the report. Schrauwen said they chose to study obese individuals given their increased risk for type 2 diabetes. In future studies, he hopes to explore the effects of resveratrol in people who have already progressed to diabetes. Resveratrol supplements are widely available, but more work is needed to establish whether they indeed have the potential to overcome the metabolic aberrations associated with obesity and aging, according to the researchers. “I don’t see a reason for particular caution, but we do need long-term studies,” Schrauwen said.