SHE'S SEXY. She's smiling. She's coming your way. And then she leans forward,
peers at your beer belly and purrs: "I like men. I just hate their guts."
Men in Britain have been getting this message a lot lately. The temptress is
a pouty Budweiser model who peers from bus posters and magazine pages-and she
has plenty to say. "I don't chase men who can't run away," teases one ad.
"Men who neglect themselves will never have a body like mine," taunts
another. These slights are all part of Budweiser's campaign to make British
men fret about their beer bellies-and reach for a 100-kilocalorie Bud Light,
a brew newly available in Britain.
If you live in the US, don't laugh. Light beers-which are lower in calories
than most regular beers-already make up about 40 per cent of the American
beer market and are gaining ground in Australia and mainland Europe. Industry
marketers pin the trend on a growing desire to live healthier, thinner lives.
But will avoiding your regular pint or two of full-strength beer really
portend a sleeker, sexier you? As it turns out, the answer is as murky as the
dregs at the bottom of a keg.
To be sure, pure alcohol packs calories: about 7 kilocalories (kcal) per
gram, compared with 9 kcal for fat and 4 kcal for carbohydrates and protein.
A pint of beer holds about 170 kcal-just shy of the amount in a packet of
crisps-while a glass of red wine or port contains roughly 90 kcal. These
liquid calories-which include sugars or fats to sweeten the sip-add up. It
would make sense, then, if regular drinkers have been found to weigh more
than teetotallers.
Except they haven't.
True, the beer belly exists, but it's wrongly named. It's just fat carried
where men carry it best-around the mid-section. And true, one study has found
that people who gulp down more than six non-wine (in this study, mostly beer)
alcoholic drinks per week have significantly higher waist-to-hip ratios than
people sipping wine with the same volume of alcohol, a finding that is
usually put down to lifestyle differences between beer and wine drinkers. But
when you compare drinkers with non-drinkers, the vast majority of
epidemiological studies show that moderate drinkers weigh the same-or even
less-than those who abstain.
In the most widely cited study, published in 1991, Harvard University
epidemiologist Graham Colditz and his colleagues scrutinised alcohol intake
and weight change in 138 000 men and women. The data had been collected by
questionnaire since 1980 as part of two ongoing studies-the Nurses Health
Study and the Health Professionals Follow-up Study-designed to find out how
lifestyle affects health in the long-term. It showed that men who drank
moderate amounts of wine or beer gained no more weight over the years than
men who did not. Women who similarly indulged actually appeared to suffer
less middle-aged spread, with a body mass index about 15 per cent lower than
non-drinkers. Similarly, a 1993 British health survey found that moderate
female drinkers were about half as likely to be obese as non-drinkers.
Several short-term diet studies have echoed these findings: people who
temporarily added alcohol to their diets usually lost pounds.
"It comes as a shock, doesn't it, to see that people who drink more don't
weigh more?" marvels John Crouse, a medical researcher at Wake Forest
University in Winston-Salem, North Carolina, and author of one alcohol study.
"Some people would say that's a great stroke of luck." Luck it might be, but
finding a good explanation for what has come to be known as the alcohol
paradox has had researchers stumped for decades.
One wistful theory was that the calories in alcohol just didn't count. After
all, several studies show that people who drink secrete less insulin, a
hormone that promotes the synthesis and storage of fat. But a 1996 study put
paid to the idea that alcohol calories are somehow different to regular
calories.
For four months, 48 volunteers consumed the same number of calories each day,
with one half receiving five per cent as ethanol in a grape-flavoured drink,
and the other half receiving the same proportion as a carbohydrate powder
dissolved in the same drink.
Each volunteer spent two months on the alcohol diet and another two on the
carbohydrate diet. At the end of these periods, each person spent 24 hours
working, eating, sleeping and just hanging out in a whole-body calorimeter-a
room rigged with equipment to monitor everything that goes into a person
(food, liquids, air) and everything that comes out (faeces, urine and
respiratory gases). On average, the same number of calories were burnt by
each person, and the same number were stored as fat, regardless of whether
they had consumed alcohol, says research physiologist William Rumpler of the
US Department of Agriculture in Beltsville, Maryland, who ran the study. His
disappointing conclusion: a calorie is just a calorie, even when it's lolling
inside a good Cabernet.
Rumpler's studies did confirm that the body deals with alcohol unusually
quickly. That makes sense since alcohol is treated by the body as a poison,
and liver enzymes immediately convert it into the more benign acetate. But
this really just amounts to normal metabolism on fast-forward, Rumpler says,
and it doesn't magic away calories.
Another hypothesis for why alcohol may not wreck your waistline is that
drinkers cut back on their food-consciously or subconsciously-in an attempt
to compensate for the liquid calories. "The whole mystery may come down to
the fact that people in epidemiology studies don't report their alcohol and
food intake accurately," says William Lands, a senior adviser at the National
Institute on Alcohol Abuse and Alcoholism near Washington, DC.
Notwithstanding the current epidemic of Western obesity, humans and other
animals are remarkably adept at regulating their calorie intake. "If you eat
more and more mashed potatoes, you eat less and less of other foods," says
Lands. "What happens when you drink more and more alcohol? We really don't
know."
Rumpler, for one, hopes to find out. His lab plans to launch a study in
February that will provide people with all their food for four months.
Halfway into the study, the researchers will add alcohol to the participants'
diets-and then check to see if they cut back on food, and if so which foods
and how much. "Hopefully, we can solve this paradox once and for all,"
Rumpler says.
If researchers do discover that people atone for alcohol calories by eating
less, it probably won't be happening during the actual headiness of
intoxication. That lowers inhibitions-including any resolve to nibble
sparingly, according to a study published in February in The American Journal
of Clinical Nutrition. In that study, biologists Margriet
Westerterp-Plantenga and Christianne Verwegen of Maastricht University in the
Netherlands served 52 people alcohol (wine or beer), fruit juice or water 30
minutes before lunch once a week for five weeks. The diners were then given a
scientific salad lunch-a plate piled with precise amounts of cold pasta,
beans, ham and other foods. A weighing scale resting under the plate-and a
hidden observer counting every bite chewed-determined how much of the lunch
each volunteer consumed. Those who knocked back alcohol beforehand ate more
food, ate more quickly, and took longer over lunch than their peers.
Which leaves at least one more plausible explanation for why drinkers tend to
be slimmer than non-drinkers: perhaps they are just more svelte to begin
with. Overweight women-those at least 4.5 kilograms heavier than the
recommended weight-may pile on the pounds as a result of drinking, while thin
women don't, according to a 1995 study by nutrition researcher Beverly
Clevidence at the US Department of Agriculture. On the surface, that finding
seems to contradict the diet studies which mostly suggest that temporarily
downing alcohol makes you lose weight. But dig deeper, and all becomes clear.
Although the earlier studies found that on average people lose weight when
they drink, the few obese volunteers in the studies actually gained weight.
Why might heavier drinkers be at a disadvantage? One idea is that alcohol
affects insulin levels differently in thin and obese people. On average,
people who drink alcohol secrete less insulin. But at least one study has
found no such effect in obese women, says physiologist Loren Cordain of
Colorado State University in Fort Collins. Researchers don't know why.
In fact, Cordain adds, until scientists understand far more about alcohol
metabolism, you might as well enjoy whatever beer you prefer-in moderation.
"Short of overdoing it, you can drink anything you please, even if it's light
beer," he says.
Whether your brew will attract a Bud Light girl is another thing altogether.
Kathryn S. Brown is a science writer based in Columbia, Missouri Further
reading: "Alcohol, calories, and appetite" by William E. M. Lands, Vitamins
and Hormones, vol 54, p 31 (1998) "Ethanol and lipid metabolism" by Lawrence
Feinman and Charles S. Lieber, American Journal of Clinical Nutrition, vol
70, page 791 (1999)
From New Scientist, 27 November 1999.
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