The study - published in The Lancet Public Health - analysed the diets of 15,400 participants in the U.S. to estimate how many calories they got from carbohydrates, fats, and protein. And, for those that are basing their low carb diet on a high meat and fat content to replace the lack of fuel-giving carbohydrates, the news is even grimmer, according to The Guardian.
The most popular diets such as Atkins are said to be so promising for the weight loss and preventing some of the diseases but now the fact comes from a United States study that if you are going to switch the meat-based meal with plant-based meal, that is comparatively more healthy. They looked at 15,428 adults ages 45-64 years in four different communities in the US between 1987 and 1989.
People whose diet was made up of less than 40 per cent and or more than 70 per cent carbohydrates had a higher mortality risk.
They found that 50-year-olds eating a moderate carb diet, with half their energy coming from carbohydrates, had a further life expectancy of 33 years, which was four years longer than those on low-carb diets and one year longer than those who ate a high-carb diet.
"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", Seidelmann said.
Replacing meat with plant-based fats (such as avocados and nuts) and proteins (such as soy products and lentils) reduces the risk of mortality, Seidelmann and her team found. The participants had to self-report their diets, based on which the researchers estimated the proportion of calories they got from carbohydrates, fats, and protein.
Those who had a moderate carb intake had four years added to their life expectancy compared to those with very low carb consumption, and one year more than those with high consumption. "Current guidelines have been criticized by those who favor low-carb diets, largely based on short term studies for weight loss or metabolic control in diabetes, but it is vital to consider long-term effects and to examine mortality, as this study did", said Nita Forouhi, Program Leader of the Nutritional Epidemiology program at the University of Cambridge.
Researchers also found that replacing carbohydrates with protein and fat from animal sources was associated with a higher risk of mortality than moderate carbohydrate intake whereas replacing with plant-based foods was linked to a lower risk of mortality.
The researchers then pulled data from seven other studies, as well as their own study, to perform a separate analysis involving more than 432,000 people in 20 countries. What's more, earlier studies have not addressed the source or quality of proteins and fats consumed in low-carb diets.
Co-author Walter Willett, a professor at the Harvard School of Public Health, said: 'These findings bring together several strands that have been controversial.
All participants reported consuming 600 to 4,200 kcal per day for men and 500 to 3,600 kcal for women, with those with particularly high or low caloric intake excluded from the analysis. For a long time, we have heard about the bad effects of sugar, and advice on the benefits of eating low-carb diets. Although carbohydrates are technically not an essential nutrient (unlike protein and fats), a certain amount is probably required to meet short-term energy demands during physical activity and to maintain fat and protein intakes within their respective sweet spots.