Fat visible under skin emerges as protector of females' brains: Study

Tbilisi, Dec 13 (IANS) The subcutaneous fat that appears under the skin in places such as the hips, buttocks and back of the arms emerges as protective against brain inflammation in females, a new study has shown.

According to the study by the Medical College of Georgia, this brain inflammation in females could result in problems like dementia and stroke, at least until menopause.

However, males of any age are more likely to deposit fat around the major organs in their abdominal cavity, known as visceral adiposity.

As a result, males are considered to be at greater risk for inflammation-related problems, such as heart attacks and strokes before females reach menopause.

"When people think about protection in women, their first thought is estrogen," said Alexis M. Stranahan, PhD, a neuroscientist at the Medical College of Georgia.

"But we need to get beyond the kind of simplistic idea that every sex difference involves hormone differences and hormone exposure," she added.

The researchers experimented on the male and female mice to look at the increase in the amount and location of fat tissue as well as levels of sex hormones and brain inflammation, to learn more about how the brain becomes inflamed.

Since, much like with people, obese female mice tend to have more subcutaneous fat and less visceral fat than male mice.

After further experiments, the researchers found that the subcutaneous fat loss increased brain inflammation in females without moving the dial on levels of their estrogen and other sex hormones, the study revealed.

"When we took subcutaneous fat out of the equation, all of a sudden the females' brains start to exhibit inflammation the way that male brains do, and the females gained more visceral fat," said Stranahan.

She also added that "the females who did not have subcutaneous fat removed but did eat a high-fat diet, showed brain inflammation levels similar to the males".

When subcutaneous fat was removed from mice on a low-fat diet at an early age, they developed a little more visceral fat and a little more inflammation in the fat.

However, Stranahan and her colleagues found no evidence of inflammation in the brain.

Stranahan notes that some consider the reason that females have higher stores of subcutaneous fat to enable sufficient energy stores for reproduction.

"But many questions remain like how much fat is needed to maintain fertility versus the level that will affect your metabolism," she added.