Call it the middle-aged spread or a beer belly, but most of us experience increased girth around our mid-section as we age. Now science has found a reason. A newly discovered type of fat cell precursor appears around middle age, causing increased belly fat no matter how much we diet and exercise.
According to Study Finds, researchers at the City of Hope Medical Center and UCLA found that 80% of the fat cells identified in middle-aged mice were new. This contests the old theory that existing fat cells simply enlarge with age.
For the study, the scientists examined the fat cells of 12-month-old mice, who are roughly the equivalent in age to 40-year-old humans, and discovered an entirely new type of fat cell precursor called CP-A that appears during middle age and multiplies rapidly, transforming into mature fat cells.
The same CP-A cells were identified in humans, and they increased with age, peaking during middle age and then declined in later years. Our bodies begin making these new fat cells when we hit our 40’s and they occur mainly in the deep belly fat that surrounds our organs, also known as visceral fat.
The team also found that a cell receptor called LIFR, or leukemia inhibitory factor receptor, drives the CP-A cells. When this receptor was blocked with drugs, it prevented the visceral fat expansion in the mice.
The discovery, published in Science, could lead to new pathways of prevention of age-related obesity, which in turn can lead to metabolic disorders. Visceral fat contributes to metabolic syndrome, a cluster of conditions that increases the risk of heart disease, stroke, and diabetes. These conditions include high blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol levels.
Studies have shown that individuals with higher amounts of visceral fat have an increased risk of premature death, regardless of their overall body weight. This highlights the critical importance of monitoring and managing abdominal fat.
In some cases, medical interventions may be necessary. Medications that target visceral fat or its metabolic pathways could offer new hope for individuals struggling to manage this dangerous type of fat. Ongoing research into the role of CP-A cells and the LIFR receptor may provide novel therapeutic options, according to Science Daily.
"Our findings highlight the importance of controlling new fat-cell formation to address age-related obesity," said Wang. "Understanding the role of CP-As in metabolic disorders and how these cells emerge during aging could lead to new medical solutions for reducing belly fat and improving health and longevity,” said Qiong (Annabel) Wang, Ph.D., the study's co-corresponding author and an associate professor of molecular and cellular endocrinology at City of Hope's Diabetes & Metabolism Research Institute.