Follow UK Immigration and UK Life: Midlife weight gain is a problem that troubles many men and women once they reach a certain age. Now, scientists claim they are one step closer to understanding the reasons behind it.
According to a report by the UK's Daily Mail on January 3, scientists believe the reason may lie in the fact that one of the two types of fat in the human body becomes less active as we age.
One type is the more familiar white fat, which is found under the skin of the abdomen and thighs and is the result of overeating.
The other type is brown fat, whose job is to generate heat. It does this by boosting metabolism, allowing people to burn off the "bad" white fat.
It has long been known that brown fat exists around the shoulder blades of infants to help them maintain body temperature after birth.
However, until recently, it was believed that this good fat disappeared during infancy because the human body no longer needed it.
New research shows that brown fat continues to exist in adulthood, and women have more brown fat than men.
Now, in a new study, Japanese scientists have discovered that as people age, the heat-generating activity of their brown fat decreases.
This means that brown fat is less active than before, and therefore burns less of the "bad" white fat.
Dr. Gerald Weissmann, editor-in-chief of The FASEB Journal, which published the study, said: "A common complaint is that older people have to work twice as hard at diet and exercise to achieve half the results of younger people."
"Now we have a better understanding of why this happens—our brown fat stops working as we get older."
"Unfortunately, until a way to restart it is developed, we have to be prepared to eat more salads and lean proteins, while also running more on the treadmill than younger people."
In this latest study, Japanese researchers also discovered a potential metabolic switch that could reactivate brown fat.
The report notes that this discovery could pave the way for the development of new treatments for obesity-related conditions such as diabetes, heart disease, high blood pressure, and certain cancers.
Researchers at the University of Shizuoka in Japan obtained these findings by studying two groups of mice.
The first group of mice had their platelet-activating factor receptor (PAFR) gene disrupted, which made them obese. The second group was normal.
The researchers found that the PAFR deficiency caused brown fat to stop working properly, thereby causing obesity due to reduced heat-generating activity.
The report states that many people worry about losing their attractiveness due to midlife weight gain, but it is also harmful to health.
Fat around organs is linked to diabetes and heart disease, and a "pot belly" also increases the risk of heart problems.
It is believed that to maintain a stable weight, people over 45 need to consume 200 fewer calories per day than younger people.
There are various theories about the best way to avoid midlife weight gain.
One study suggests that a low-fat, high-sugar diet might be the key to staying slim, but this diet is only effective if the sugar comes from unprocessed foods containing high fiber.
Another expert, Mary Savard, says a better option is to do 30-45 minutes of moderate-intensity exercise at least five days a week.
