Further proof that moderation is the key to optimal health, a recent study by medical doctors at Brigham and Women’s Hospital in Boston has found that both low-carb and high-carb diets are linked to an increased risk of early death.
The study, published in The Lancet, followed 15,428 adults in the U.S. between the ages of 45 and 64 who had filled out a dietary questionnaire between 1987 and 1989 when they enrolled in a Atherosclerosis Risk in Communities (ARIC) study. They then combined that data with carbohydrate intake data from seven other studies.
After following up with them a median of 25 years later, there were 6,283 deaths. Not only did they find that the rate of deaths increased in those who got over 70% of their dietary energy from carbohydrates, they found that those who were on low-carb diets (less than 40%) also experienced an increase in mortality rates. The “sweet spot” where subjects were at the lowest risk were those who got 50% to 55% of their energy from carbs.
Taking their findings a step further, they found that the type of food those on low-carb diets substituted for carbs also mattered. Mortality increased further when animal-derived proteins and fats replaced carbs and decreased when they were replaced by plant-based fats and proteins.
The team also used their research to calculate life expectancy and found that 50-year-olds with moderate carb intake were expected to live an additional 33 years. Meanwhile those on high-carb diets were expected to live 32 years and those on low-carb diets were expected to live 29 years.
Dr. Sara Seidelmann, who led the research, told CNN that she was motivated to do this study because of the growing popularity of cutting carbs as a healthier way of eating. While research has found that it has short-term weight loss and cardiovascular benefits, she was curious to see the long-term impact. “We need to look really carefully at what are the healthy compounds in diets that provide protection,” she said.
Still, the researchers themselves stress that this is an observational study and correlation does not necessarily mean causation. However, it’s food for thought for anyone considering going on a low-carb diet in the name of their health. And if you do decide to make low-carb a lifestyle, you probably want to moderate your meat intake as well.
