Carbs Affect Death Risk More Than Fat

A large, 18-country study suggests that it is not the fat in your diet that’s raising your risk of premature death; it’s too many carbohydrates --especially the refined, processed kinds of carbs -- that may be the real killer.

The research also found that eating fruits, vegetables and legumes can lower your risk of dying prematurely. But three or four servings a day seemed to be plenty. Any additional servings didn’t appear to provide more benefit, sbs.com.au reported.

People with a high fat intake -- about 35% of their daily diet -- had a 23% lower risk of early death and 18% lower risk of stroke compared to people who ate less fat, said lead author Mahshid Dehghan. She’s an investigator with the Population Health Research Institute at McMaster University in Ontario.

The researchers also noted that a very low intake of saturated fats (below 3% of daily diet) was associated with a higher risk of death in the study, compared to diets containing up to 13% daily.

At the same time, high-carb diets -- containing 77% carbohydrates on average -- were associated with a 28% increased risk of death versus low-carb diets, Dehghan said.

“The study showed that contrary to popular belief, increased consumption of dietary fats is associated with a lower risk of death,” she said.

“We found no evidence that below 10% of energy by saturated fat is beneficial, and going below 7% may even be harmful. Moderate amounts, particularly when accompanied with lower carbohydrate intake, are probably optimal,” she said.

These results suggest that leading health organizations might need to reconsider their dietary guidelines, Dehghan noted.

Dr. Christopher Ramsden, a clinical investigator with the US National Institute on Aging, also said that, “There’s a lot more information that’s needed. They did a great job and they’re going to have a lot more coming out of it for years to come, but it’s hard to get it down to recommendations regarding food at this point.”

“It really highlights the need for well-designed randomized controlled trials to answer some of these questions,” Ramsden added.

The researchers noted that their study did not look at the specific types of food from which nutrients were derived.

 Creating a Balance

“For example, eating a healthy carb, like an apple, is more nutrient-dense and better for you than eating a bag of processed potato chips,” he said.

Current global guidelines recommend that 50% to 65% of a person’s daily calories come from carbohydrates, and less than 10% from saturated fats, the researchers said.

Dehghan suggested that “the best diets will include a balance of carbohydrates and fats, approximately 50 to 55% carbohydrates and around 35% total fat.”

For this study, Dehghan and her colleagues tracked the diet and health of more than 135,000 people, aged 35 to 70, from 18 countries around the world, to gain a global perspective on the health effects of diet.

Participants provided detailed information on their social and economic status, lifestyle, medical history and current health. They also completed a questionnaire on their regular diet, which researchers used to calculate their average daily calories from fats, carbohydrates and proteins.

The research team then tracked the participants’ health for about seven years on average, with follow-up visits at least every three years.

High-carbohydrate diets have been linked with increases in both blood cholesterol and in the chemical building blocks of cholesterol, Dehghan said.