Gaby
When you picture a smoker, you might imagine a slim, Audrey Hepburn–style figure. But a new study found that even thin smokers can carry a surprising amount of unhealthy belly fat—specifically, visceral fat.
Many people believe smoking suppresses appetite, and that quitting will lead to weight gain. But researchers say that idea is misleading. Even people who keep a relatively low weight can still accumulate a considerable amount of deep abdominal fat. In other words, a flat stomach can hide a dangerous reserve of fat.
What Scientists Discovered
People who don’t tend to gain weight but who have smoked for many years still risk building up significant reserves of the most harmful type of fat—visceral fat. This fat wraps around the internal organs in the abdomen and is much harder to shift than subcutaneous fat. It’s also linked to a higher risk of heart attacks, diabetes, and dementia.
To test the connection between lifelong smoking and visceral fat, researchers at the University of Copenhagen used a statistical method called Mendelian randomization (MR). This approach helps identify causal relationships by grouping individuals according to genetic differences.
The team applied MR to data from European genetic studies that looked at how smoking affects fat distribution. That included a large study of 1.2 million people who had recently started smoking and more than 450,000 lifelong smokers. Another study examined fat distribution in 600,000 participants.
First, the researchers identified which genes were associated with smoking habits and with fat distribution. They then used that genetic information to compare where fat accumulated in smokers versus non-smokers.
The scientists also accounted for other factors that contribute to fat buildup, such as alcohol consumption and socio-economic status. They found that the effect of smoking on abdominal fat concentration was independent of those factors.
Dr. Herman D. Carrasquilla, the lead author of the study, said, “These results underscore the importance of large-scale efforts to prevent smoking across the population, as they may also help reduce abdominal visceral fat and all associated chronic diseases.”
The findings were published in the journal Addiction.
By the way, HouseWife previously took an in-depth look at what visceral fat is and why it poses a danger.
