Couch potatoes may no longer be able to hide behind the excuse of their genes making them overweight.
Scientists have confirmed even people who are naturally overweight because of their DNA can slim down by exercising.
A study on nearly 20,000 people found regular jogging was the best way to ‘blunt’ the effects of genes which raise the risk of obesity.
Lacing up and going for a jog was effective for reducing people’s height-to-weight ratio (BMI), body fat percentage and the size of their hips.
Scientists at the National Taiwan University studied the impact of exercise on 18,424 Chinese people between the ages of 30 and 70.
The team measured people’s bodies, noted how much exercise they did and looked at their DNA to see if they were naturally more likely to be obese.
More than 400 genes have been linked to being overweight, by affecting people’s appetites, their metabolisms or the way their bodies store fat.
‘Regular jogging mitigated the genetic effects on body mass index, body fat percentage, and hip circumference,’ said Dr Wan-Yu Lin, study author.
‘Mountain climbing, walking, exercise walking and international standard dancing also attenuated the genetics effects on BMI.’
People in China are significantly less fat than those in the UK and US – the country has an obesity rate of just seven per cent among over-15s, according to the Organisation for Economic Co-operation and Development (OECD).
In the UK this rate is 26.9 per cent and the US 38.2 per cent.
Past research has suggested this is because people in China spend less time sitting down, are more active, and eat more carbohydrate and less fat.
As well as the BMI, body fat and hip size, the Taiwanese scientists also measured people’s hip-to-waist ratio and their genetic risk scores (GRS), which dictate the role their DNA plays in obesity.
And they considered the effects of 18 different types of exercise on helping people to slim down.
Dr Lin added:
‘Among the 18 kinds of self-reported regular exercise, six mitigated the genetic effects on at least one obesity measure.
‘Across all five obesity measures, regular jogging consistently presented the most significant interactions with genetic risk scores.’
The team claimed, however, that cycling, swimming, the video game Dance Dance Revolution and Qigong – a tai chi-like martial art – do not have the same effect.
‘Cycling, stretching exercise and qigong usually require less energy expenditure than the six exercise that demonstrate interactions with GRS,’ said Dr Lin.
‘Exercises in cold water such as swimming can especially stimulate appetite and food intake.
‘Dance Dance Revolution, a computer game based on dancing with music videos, is not as formal as international standard dancing.
‘These reasons may possibly explain why these five popular exercises cannot mitigate genetic susceptibility to obesity measures.’
The research was published in the journal PLOS Genetics.