Cutting out just over two teaspoons of sugar a day can make your body younger, research suggests.

The University of California found that removing 10g of sugar daily can reverse a person’s biological clock by 2.4 months.

The study found that people who eat less sugar are biologically younger, despite their chronological age.

Researchers looked at the food records of 342 women aged 39 years old on average and took saliva samples to measure their biological age using an internal clock.

Over the course of a lifetime, chemical “tags” are added to a person’s DNA which can be used to measure how well a body is ageing. More tags, means the clock is ticking faster and a person is biologically older.

The scientists found that the healthier people ate, the slower their internal clock was ticking, but sugar had a detrimental effect even if people ate well otherwise. Each gram of added sugar was associated with an increase in their internal age.

Dr Barbara Laraia, professor in the Food, Nutrition and Population Health programme at UC Berkeley, said: “Given that epigenetic patterns appear to be reversible, it may be that eliminating 10 grams of added sugar per day is akin to turning back the biological clock by 2.4 months, if sustained over time.

“Focusing on foods that are high in key nutrients and low in added sugars may be a new way to help motivate people to eat well for longevity.”

The NHS recommends that adults in Britain should consume no more than 30 grams of free sugars a day, which is roughly the equivalent of seven sugar cubes.

Women in the study were consuming more than double the recommended limit on average at 61.5g, although some ate as much as 316g daily.

A bar of milk chocolate has about 25 grams of added sugar, while a can of cola has about 39 grams. Cutting out 10g is the equivalent of abstaining from two chocolate digestives each day or about two and a half teaspoons of sugar.

For the study, researchers scored the women’s diets to see how they compared to a Mediterranean-style diet rich in anti-inflammatory and antioxidant foods and then to a diet linked to lower risk for chronic disease.

They also looked at levels of important nutrients such as Vitamins A, C, B12 and E, folate, selenium, magnesium, dietary fibre and isoflavones.

Adherence to any of the diets was significantly associated with lower epigenetic age, with the Mediterranean diet having the strongest association.

Cause of so many problems

The researchers examined sugar intake separately and found that consuming foods with added sugar was associated with accelerated biological ageing, even in the presence of an otherwise healthy diet.

Dr Dorothy Chiu, of UC San Francisco (UCSF) Osher Center for Integrative Health, said: “The diets we examined align with existing recommendations for preventing disease and promoting health, and they highlight the potency of antioxidant and anti-inflammatory nutrients in particular.

“From a lifestyle medicine standpoint, it is empowering to see how heeding these recommendations may promote a younger cellular age relative to chronological age.”

Eating too much sugar is known to lead to a string of conditions including heart disease, stroke, Type 2 diabetes, liver disease, obesity, and tooth decay.

Experts said the study might help explain why sugar causes so many problems.

Prof Elissa Epel, of the Department of Psychiatry and Behavioral Sciences at UCSF, said: “We knew that high levels of added sugars are linked to worsened metabolic health and early disease, possibly more than any other dietary factor. 

“Now we know that accelerated epigenetic ageing is underlying this relationship, and this is likely one of many ways that excessive sugar intake limits healthy longevity.”

The research was published in the journal Jama Network Open.