August 2, 2005 NEW YORK TIMES
Yoga May Help Minimize Weight Gain in Middle Age
By NICHOLAS BAKALAR
Practicing yoga may be one way to prevent middle-aged spread, according
to the findings of a new study.
Although the connection appears to be indirect, yoga practitioners are
apparently able to avoid - or at least minimize - the one-pound-a-year of
gained weight that most people endure between the ages of 45 and 55.
The researchers used data from more than 15,000 men and women ages 53 to
57, who reported their weight at age 45 and their current weight.
The subjects were also asked to report whether they engaged regularly in
three specific recreational activities - walking, weight lifting, and yoga -
and whether they participated in two broader categories of activity,
moderate and strenuous exercise. The researchers assessed the diet of the
study participants using a detailed food questionnaire.
Practicing yoga for 4 or more years, for at least 30 minutes once a week,
was associated with a 3.1-pound lower weight gain among people who were
normal weight at age 45. The yoga practitioners who were overweight at 45
lost an average of 5 pounds, as opposed to an average gain of 13 pounds in
overweight nonpractitioners. Being overweight was defined as having a body
mass index of 25 or greater.
Dr. Alan R. Kristal, the lead author on the study and associate director
of the cancer prevention program at Fred Hutchinson Cancer Research Center,
emphasized that yoga was not a magic weight control technique. "There are
many weight control strategies," he said. "But none allows you to escape the
laws of thermodynamics. If you consume more energy than you expend, then it
will be stored as fat."
But, he added, yoga offers "a safe and comfortable way for people who
have never been physically active to begin regular physical activity."
Unsurprisingly, the study found significant differences in lifestyle
between those who practiced the discipline and those who did not. Yoga
practitioners engaged in more physical activity apart from yoga than did
nonpractitioners. Longtime participants had an 11 percent lower energy
intake from fat and a 45 percent higher energy intake from fruits and
vegetables.
Participants who practiced yoga also ate more, consistent with their
higher exercise levels. But even after statistical adjustments were made to
account for this, the difference in weight gain between practitioners and
nonpractitioners persisted.
The authors conceded that their study, published in the July/August issue
of Alternative Therapies, has many limitations. Although there were more
than 1,000 people in the study who did some yoga, almost half did less than
30 minutes at a session, while normal yoga sessions usually last 60 to 90
minutes. Only 132 of these people maintained the practice longer than four
years.
In addition, the study depended on self-reports, which are not always
reliable. And the researchers pointed out that the yoga practitioners in
their survey were in better overall health than nonpractitioners
Observational studies like theirs, they said, are difficult to interpret,
and well-designed clinical trials are the best way to determine yoga's
effect on weight control.
Nevertheless, the researchers offered several possible mechanisms for an
indirect connection between yoga and weight maintenance. Even though yoga by
itself would not meet minimum requirements for daily exercise, they pointed
out, it does improve exercise capacity.
Moreover, for a sedentary person, yoga can be the beginning of more
strenuous physical activity. Yoga practitioners consistently report that
they feel "more connected" to their bodies, which may reduce food intake by
helping enhance awareness of satiety and increase sensitivity to being too
full.
Finally, yoga promotes a sense of well being, and encourages commitment
and discipline, qualities helpful in making lifestyle changes and sticking
to them, the researchers said. "In that context," Dr. Kristal said, "some of
the benefits of yoga practice may help people with some of the more
difficult aspects of weight loss."
