Pedestrians walk across the street near Times Square in a 2007 photo. (Lucas Jackson/Reuters)

NEW YORK (Reuters Health) -
If the trends of the past three
decades continue, it's possible that every American adult could
be overweight 40 years from now, a government-funded study
projects.

The figure might sound alarming, or impossible, but
researchers say that even if the actual rate never reaches the
100-percent mark, any upward movement is worrying; two-thirds
of the population is already overweight.

“Genetically and physiologically, it should be impossible”
for all U.S. adults to become overweight, said Dr. Lan Liang of
the federal government's Agency for Healthcare Research and
Quality, one of the researchers on the study.

However, she told Reuters Health, the data suggest that if
the trends of the past 30 years persist, “that is the direction
we're going.”

Already, she and her colleagues point out, some groups of
U.S. adults have extremely high rates of overweight and
obesity; among African- American women, for instance, 78
percent are currently overweight or obese.

The new projections, published in the journal Obesity, are
based on government survey data collected between the 1970s and
2004.

If the trends of those years continue, the researchers
estimate that 86 percent of American adults will be overweight
by 2030, with an obesity rate of 51 percent. By 2048, all U.S.
adults could be at least mildly overweight.

Weight problems will be most acute among African-Americans
and Mexican- Americans, the study projects. All black women
could be overweight by 2034, according to the researchers, as
could more than 90 percent of Mexican-American men.

All of this rests on the “big assumption” that the trends
of recent decades will march on unabated, Liang acknowledged.

“This is really intended as a wake-up call to show what
could happen if nothing changes,” she said.

Waistlines aren't the only thing poised to balloon in the
future, according to Liang and her colleagues. They estimate
that the healthcare costs directly related to excess pounds
will double each decade, reaching $957 billion in 2030 —
accounting for one of every six healthcare dollars spent in the

U.S.

Those financial projections are based on Census data and
published estimates of the current healthcare costs attributed
to excess weight — and they are probably a “huge
underestimate” of what the actual costs will be, Liang said.

The findings highlight a need for widespread efforts to
improve Americans' lifestyles and keep their weight in check,
according to the researchers. Simply telling people to eat less
and exercise more is not enough, Liang noted.

Broader social changes are needed as well, she said — such
as making communities more pedestrian-friendly so that people
can walk regularly, or getting the food industry to offer
healthier, calorie-conscious choices.

“It really needs to be more than an individual effort,”
Liang said. “It needs to be a societal effort.”

SOURCE: Obesity, online July 24, 2008.