Eating a low carb diet could shorten your life, according to new research

Eating a low carb diet could shorten your life

Although most runners won’t be following a low-carb diet, as a nation, cutting carbs seems to be a trend in recent years, with many people believing a low-carb diet to be the key to weight loss.

In a large study of 15,400 people aged 45-64 in the US, researchers set out to investigate what effect a high, or low carb diet had on mortality.

The study, published in The Lancet Public Health, took place over 25 years’. At the beginning of the study, and six years later, participants filled out questionnaires determining the food and drink they consumed, along with their portion sizes. From this, scientists were able to estimate the proportion of calories they got from carbohydrates, fats and protein.

Related: New study shed light on how a runner’s diet affects menopause 

Based on the questionnaire, researchers divided participants into four different groups:

- The moderate carb group, who got 50-55% of their energy from carbohydrates (in line with current UK dietary guidelines).

- The extra-low-carb group, who got less than 30% of their energy from carbs.

- The low-carb group, who got 30-40% of their energy from carbs.

- The high-carb group, who got more than 65% of their energy from carbs.

After studying the data 25 years later, researcher estimated that, from the age of 50, people in the moderate carb group were, on average, expected to live for another 33 years. This was four years more than the extra-low-carb group, 2.3 years more than the low-carb group, and 1.1 years more than the high-carb group.

Eating a low carb diet could shorten your life

Researchers also found that what the carbs were replaced with on the plate makes all the difference. Eating more beef, lamb, pork, chicken and cheese in place of carbs was linked with a higher mortality rate. In contrast, replacing carbohydrates with plant-based products was found to reduce the risk of mortality.

Related: 7 ways to fit more plant-based food into your diet 

Dr Sara Seidelmann, who led the research said: “Low-carb diets that replace carbohydrates with protein or fat are getting widespread popularity as a health and weight-loss strategy.

“However, our data suggests that animal-based low carbohydrate diets, which are prevalent in North America and Europe, might be associated with shorter overall life span and should be discouraged.

“Instead, if one chooses to follow a low carbohydrate diet, then exchanging carbohydrates for more plant-based fats and proteins might actually promote healthy ageing in the long term.”

Of course, as with all research, there are limitations. Firstly, the findings are based on self-reported data, which might not be accurate. Also, as participants were only asked about their diets at the beginning of the study and six years into it, it’s hard to conclude their diets had not changed in the subsequent 19 years.