American Heart Association
Repeatedly losing and regaining weight, known as weight cycling
or yo-yo dieting, may increase the risk of death from heart disease among postmenopausal
women who were of normal weight at the start of the study, according to
research presented at the American Heart Association's Scientific Sessions
2016.
"Weight cycling is an emerging global health concern
associated with attempts of weight loss, but there have been inconsistent
results about the health hazards for those who experience weight cycling
behavior," said Somwail Rasla, M.D., study lead author and internal
medicine resident at Memorial Hospital of Rhode Island, Alpert Medical School,
Brown University, in Providence, Rhode Island.
Researchers classified self-reported weight history from 158,063 post-menopausal women into four categories: stable weight, steady gain, maintained weight loss, and weight cycling. During a follow-up of 11.4 years, they found:
Women considered "normal-weight" at the start of the
study who lost and regained weight had about three and a half times higher risk
for sudden cardiac death than women whose weight remained stable.
Weight cycling in the normal-weight women was also associated
with a 66 percent increased risk for coronary heart disease deaths.
No increase in either type of death occurred among overweight or
obese women reporting weight cycling.
Similarly, no increase in death occurred among women who reported
that they gained weight but did not lose it or, in the opposite scenario, that
they lost weight without gaining it back.
Evidence indicates that being overweight in midlife increases
the risk of dying from two types of heart disease.
In the first type, coronary
heart disease, the blood vessels to the heart become blocked by fat and other
substances, decreasing blood flow to the heart.
In the second type, sudden
cardiac death, the heart's electrical system abruptly stops working, causing
death. It is unclear whether losing and regaining weight in adulthood also
increases the risk of death from these heart diseases, so the investigators
looked at this relationship among postmenopausal women.
The study has several limitations. First, the study was observational,
therefore it could only show association and not a cause and effect
relationship. In addition, the study relied on self-reports, which could be
inaccurate.
Since sudden cardiac death occurred relatively infrequently, the
cases that did occur could have resulted from chance. Finally, the study
included only older women.
"More research is needed before any recommendations can be
made for clinical care regarding the risks of weight cycling, since these
results apply only to postmenopausal women and not to younger-aged women or
men," Rasla said.
In the United States and worldwide, heart disease is the leading
cause of death. Obesity is a major risk factor, along with high blood pressure
and cholesterol, diabetes, physical inactivity, poor diet, and smoking. One way
to lower your risk factors is by following the American Heart Association's
Life's Simple 7 program, which recommends:
(1) manage blood pressure;
(2)
control cholesterol;
(3) reduce blood sugar;
(4) get active;
(5) eat better;
(6) maintain normal weight; and
(7) stop smoking.
This study is funded by the National Heart Lung and Blood
Institute.