Losing weight makes you look and feel better, and it could add some smarts, too.

A new study suggests obesity may speed up the decline of thinking and memory.

Researchers studied more than 6,000 middle-aged British men and women and found people who were obese and had high blood pressure, or other poor health conditions, showed a 23% faster decline in memory and thinking skills than others.

Researchers collected the participants' body mass index and metabolic measurements. Their cognitive skills, such as memory, reasoning and verbal skills, were also tested three times over a decade until 2009.

Of all the participants, 60% (350) were classified as obese and metabollically abnormal (identified as having two or more risk factors: high blood pressure, low good cholesterol, high blood sugar and/or high levels of fats in the blood).

The metabolically normal obese individuals also experienced a more rapid decline, the study said.

Leader author Archana Singh-Manoux, with the research institute INSERM in Paris and the University College London in the U.K., cautioned that the study doesn't condone "metabolically healthy obesity."

The study was published online Tuesday in the journal Neurology.