Desserts and other things causing obesity

David Allison, a University of Alabama biostatistician, invited 19 other scientists in the United States, Canada and Italy, to work on the report.

Photo: Desserts and other things causing obesity

They looked at more than 100 studies on potential contributors to obesity besides diet and exercise, and concluded there was at least some support for 10.

Inadequate sleep. (Average sleep amounts have fallen, and many studies tie sleep deprivation to weight gain.)

- Endocrine disruptors, which are substances in some foods that may alter fats in the body.

- Nice temperatures. (Air conditioning and heating limit calories burned from sweating and shivering.)

- Fewer people smoking. (Less appetite supression.)

- Medicines that cause weight gain.

- Population changes in the United States. (More middle-agers and Hispanics, who have higher obesity rates.)

- Older birth moms. (That correlates with heavier children).

- Genetic influences duringpregnancy.

- Darwinian natural selection. (Fat people outsurvive skinny ones).

Not that people necessarily should try to alter these factors, Allison said. For example, "we would never recommend that people start smoking to reduce their body weight."

The same for medications that can lead to weight gain, though doctors may want to consider alternatives if a patient piles on pounds.

School nutrition expert who is past president of the Obesity Society, the leading group of researchers in the field, according to the AP.