Why even slim women risk obesity

Australian researchers have issued what could be a wake-up call for young women who are complacent about weight gain.

New evidence suggests that rates of weight gain are established by the time women are 18-23 years old.

So even those with a healthy BMI, but who are consistently putting on some weight in their early 20s, could be set on a dangerous trajectory.

Those who smoke, or who are divorced, separated or widowed are particularly prone to weight problems as they age.

The researchers suggest opportunistic screening of young women could identify those who are likely to run into difficulty by the time they hit 40.

A gain of more than 200g per year is considered higher than optimal, they say.

Data from their 16-year study of 4881 women with a healthy BMI at baseline showed 59% remained in the healthy BMI category, 29% transitioned to overweight and 11% became obese.

Mean rates of weight gain were 0.19kg/year (for those who remained healthy weight), 0.84kg/year (for those who became overweight) and 1.74kg/year (for those who became obese).

In adjusted models, women with higher education were 50% more likely to remain a healthy weight than those with lower education.

Interestingly, women who drank up to two standard alcoholic drinks per day were 25% more likely to maintain a healthy weight than those who never or rarely drank.

“Understanding the individual characteristics [that enable women to maintain a healthy BMI] in the face of current obesogenic environments could help to address one of the most important contemporary public health challenges: obesity prevention,” write the researchers, led by Professor Wendy Brown, University of Queensland.

The study was published in the American Journal of Preventive Medicine and presented at the European Congress on Obesity in Portugal this week.