It’s one of the most common weight loss requests.
But targeting fat loss from specific areas of the body — whether your thighs or belly — is ‘simply not possible’, a leading weight loss scientist has claimed.
Ads for exercises, pills and supplements often claim they will blitz fat in one part of the body.
Dr Nick Fuller, an author and lecturer in the treatment and management of obesity at the University of Sydney, labelled targeted fat-loss — or ‘spot reduction’ — a ‘myth’.
Instead, factors out of your control, such as genes, gender and age, as well as how much fat and muscle a person has, dictates the areas and order in which our bodies store and lose fat, he said.
Dr Nick Fuller (pictured), an author and senior lecturer in the treatment and management of obesity at the University of Sydney , said factors outside of our control influence the areas and order in which our bodies store and lose fat
Studies have also shown genes can account for up to 60 per cent of where body fat is distributed, Dr Fuller argued. Gender and age may also play a role, with changes to muscle mass, metabolism and hormone levels impacted by the ageing process. ‘Women tend to lose weight from their face, calves and arms first because they impact childbearing the least, while holding onto fat stored around the hips, thighs and buttocks,’ he added
Writing in The Conversation, he added: ‘Our muscles can’t directly access and burn specific fat stores when we exercise.’
Instead, they use a process called lipolysis to convert triglycerides — harmful fats in the blood — into free fatty acids and a compound called glycerol, ‘which then travels to our muscles via our bloodstream’.
‘As a result, the fat stores we’re using for energy when we exercise come from everywhere in our bodies – not just the areas we’re targeting for fat loss,’ he said.
Additionally, research suggests that working out specific muscles has little impact on reducing fat in that area.
One 2015 study of 45 women who followed a weight-loss diet found that those who also performed abdominal exercises saw no greater improvement in reducing belly fat compared to those who only dieted.
Iranian researchers concluded that ‘there were no significant differences between the groups’.
Studies show that genes, gender and age all influence where people put on and lose fat.
Genes can account for up to 60 per cent of where body fat is distributed, meaning that where a person’s parents store fat is often a marker of where they will as well, Dr Fuller said.
Gender also plays a role. For example, women store more fat than men — to support pregnancy and breastfeeding — and tend to lose weight from their face, calves and arms first, as this has the least impact on childbearing, according to Dr Fuller.
Age influences where the body stores fat, with post-menopausal women and middle-aged men tending to put on fat around their stomach, which they struggle to shift, he said.
Additionally, pills and supplements that claim to blast fat are not supported by substantial evidence, Dr Fuller claimed — even if ads claim they are back by clinical trials and scientific evidence.
Two recent studies by researchers at the University of Sydney, which examined more than 120 trials of herbal and dietary supplements that claim to aide weight loss, found there was ‘insufficient evidence’ behind the claims.
Therefore, spot reduction is a ‘myth’ and it is impossible to control where the body loses fat from, he said.
Instead, people can only try to achieve overall fat loss, which will change body shape and help with long-term weight management, Dr Fuller added.
Dr Fuller, author of Interval Weight Loss and Interval Weight Loss for Life, said: ‘This is because your metabolic rate — how much energy you burn at rest —is determined by how much muscle and fat you carry.’
Someone with a higher muscle mass will have a faster metabolic rate than those who are the same weight but have a higher fat mass, he said.
Those seeking to look slimmer should lose weight in ‘small, manageable chunks’ that they can sustain, with every period of weight loss followed by time spent maintaining weight, until a goal weight is achieved, he said.
A lack of exercise, combined with unhealthy diets, has been blamed for the growing obesity epidemic in the UK.
Latest NHS data shows 26 per cent of adults in England are obese and a further 38 per cent are overweight but not obese.
They are also high among children, with a quarter of children in reception classes in England now considered overweight, and one in ten obese.
A landmark study published in May revealed the UK’s bulging waistline is stripping billions of pounds from the cash-strapped NHS each year, with twice as much spent on obese patients as on those of a healthy weight.
Costs per patient rise drastically the more people weigh, as they ‘collect obesity-related conditions’ such as type 2 diabetes, cancer and heart disease, according to research involving nearly 2.5million people.