Expert warns smoking can increase belly fat

In a twist, cigarettes can actually cause an increase in belly fat – so no more smoking ‘to stay thin’. 

New research suggests smoking can increase visceral fat which is linked to a higher risk of heart disease, diabetes, stroke, and dementia.

The study, published in the journal Addiction, found both starting smoking and lifetime smoking may increase the amount of unhealthy fat deep inside the abdomen.

Visceral fat is hard to see, meaning smokers can have a flat stomach and still have unhealthy amounts of it, which raises the risk of serious illness.

Researchers from the University of Copenhagen in Denmark used a form of statistical analysis called Mendelian randomisation (MR) to determine whether smoking causes an increase in abdominal fat.

The analysis combines the results from different genetic studies to look for causal relationships between exposure, smoking, and outcome, increased abdominal fat.

Then the researchers looked at results from European ancestry studies of smoking exposures and measures of body fat distribution, in the form of waist-hip ratio and waist and hip circumferences.

The smoking study looked at 1.2 million people who started smoking and over 450,000 lifetime smokers, and the body fat distribution study included over 600,000 people.  

First, the researchers used previous genetic studies to identify which genes are linked to smoking habits and body fat distribution. 

Then they used this genetic information to determine whether people with genes associated with smoking tend to have different body fat distributions.

The findings showed that starting to smoke and smoking over a lifetime might cause an increase in belly fat, as seen by measurements of waist-to-hip ratio. 

They also found that the type of fat that increases is more likely the visceral fat, rather than the fat just under the skin.

Lead author Dr Germán Carrasquilla said: ‘Previous studies have been prone to confounding, which happens when an independent variable affects the results. Because our study design uses genetic variations, it does a better job of reducing or controlling for those variables. 

‘The influence of smoking on belly fat seems to happen regardless of other factors such as socioeconomic status, alcohol use, ADHD, or how much of a risk-taker someone is.

‘From a public health point of view, these findings reinforce the importance of large-scale efforts to prevent and reduce smoking in the general population, as this may also help to reduce abdominal visceral fat and all the chronic diseases that are related to it. 

‘Reducing one major health risk in the population will, indirectly, reduce another major health risk.’

Follow Metro across our social channels, on Facebook, Twitter and Instagram

Share your views in the comments below