Doctor explains why you can't lose body fat - and 'it's nothing to do with calories'

A health expert has explained why you are probably struggling to lose body fat - and he says it has nothing to do with your calorie intake, but rather your insulin resistance levels. Speaking to host Steven Bartlett on a recent episode of his hit podcast show, Diary of a CEO, Dr Robert Lustig shared the reason why he thinks counting calories is pointless.

Dr Robert Lustig is a Professor of Paediatric Endocrinology and an expert on the impact sugar has on our health. He is the author of bestselling books such as, ‘Fat Chance’, ‘Metabolical’, and ‘The Hacking of the American Mind’.

Lustig says sugar intake is a "big problem" and is a primary factor in finding it hard to lose weight. Explaining why it is "poison" to our bodies, he said fructose (a component of sugar) is metabolized similarly to alcohol.

He warns how excessive consumption of sugar, like alcohol, can have detrimental effects on the body. According to the NHS, adults should have no more than 30g of free sugars a day.

Lustig said consuming more than the recommended amount of sugar can have negative effects on health. These could include metabolic, systemic, mental, and societal complications.

"We also know that if you have high sugar consumption it's got multiple detrimental effects, such as mental health problems, cognitive decline and early death. We also know it's the primary driver of Attention Deficit Disorder (ADD).

"The problem is that sugar is addictive." Alarmingly, he added: "If you consume one sugared beverage per day, your risk of diabetes goes up by 29%."

Other shocking stats the endocrinologist mentioned in the podcast include:

• Obesity is projected to become the norm by 2050.

• The percentage of obese people globally has doubled in the last 28 years.

• Metabolic syndrome can reduce life expectancy by 15-20 years.

• Sugar consumption has tripled worldwide in the last 50 years.

However, reducing sugar intake, even without weight loss, can help improve metabolic health and cognitive function. If actively trying to lose weight and body fat, Lustig says calorie counting 'isn't an efficient method'.

He explains that your body's response to food is more important than whatever calories you are taking in. In particular, this is because he says excessive sugar consumption can trigger insulin resistance, which can lead to weight gain and difficulty losing weight.

"Virtually everybody who counts calories loses a little bit of weight and then they plateau and then they get um you know tired of their diet and the weight comes rushing back," Lustig added. "90% of people who try to diet through caloric restriction regain and sometimes yo-yo back even higher."

He went on to say how yo-yo dieting is caused by insulin resistance, as opposed to calorie restrictions. According to the NHS, insulin is an energy storage hormone in the body.

Its primary function is to reduce the rise in blood glucose caused by eating or drinking. It is also the primary driver of obesity, diabetes, and metabolic syndrome.

Lustig warns refined carbohydrates and sugar can cause insulin levels to increase. He says the "best way to lose weight" is to reduce insulin levels.

To do this, you would need to cut out refined carbohydrates and dietary sugar. By doing so, the expert says your insulin resistance will improve and you'll lose weight easier.

In regards to the healthiest foods to eat, the professor says anything that has come out of the ground or from animals who eat foods from the ground is best. Added sugar makes food metabolically detrimental, even if it contains vitamins and minerals, he added.