‘Eating too much salt causes obesity’
British scientists found that every extra gram of salt that a person eats each day increases their risk of obesity by 25 per cent.
Even when they took into account the total amount of food individuals ate, salt still seemed to be a major factor in a person’s weight.
Doctors have known for some time that salt consumption is linked to high blood pressure, making it a risk factor for heart disease.
But this is the first study of its kind that links salt directly to obesity.
The researchers, led by Prof. Graham MacGregor of Queen Mary University of London, said they could not be sure exactly why salt has such a profound impact.
But they suspect that it modifies the metabolism, altering the way the body absorbs fat.
Writing in the journal Hypertension, the scientists said: “These results suggest that salt intake is a potential risk factor for obesity independent of energy intake.”
But other professionals urged caution, saying the findings were unreliable because people in the study self-reported how much they ate.
The research used data for more than 450 children and 780 adults from the UK National Diet and Nutrition Survey 2008/2009 to 2011/2012.
Experts analysed urine samples over 24 hours and calculated calorie intake from a four-day diary.
The results showed that salt intake in urine was higher in people who were overweight or obese, with an extra gram of salt a day leading to a more than 20 per cent increase in the chance of being heavy.
MacGregor, who is chairman of Consensus Action on Salt and Health, said: “The food we eat is now the biggest cause of ill health through its high salt, fat and sugar content added by the food industry.
“High blood pressure and obesity both lead to the development of cardiovascular disease, stroke, heart attacks and heart failure, which are the commonest causes of death and disability in the UK.
“Obesity also predisposes to type 2 diabetes, which further increases the risks of cardiovascular disease and can lead to severe complications.
“Such an epidemic will cripple the British National Health Service (NHS) if the increase in these diet related issues are not stopped immediately.”
The NHS suggests we eat no more than 6g salt a day – but the latest statistics show we are eating far more than we require, at 8.1g per day on average.