This is a photo of Keith Orr in the intensive care unit of a Boston hospital as he recovered from his second heart attack. It’s from Gina Kolata’s article Lessons of Heart Disease, Learned and Ignored, which, if you read it, I promise will get your heart beating just a bit faster.

A new study out of Boston’s Harvard “did not find a health benefit from greater adherence to an low‐carbohydrate diet (LCD) overall after myocardial infarction (MI).” Indeed, it found that those who ate lower-carb diets (in the range of 42% of calories) with more animal foods died sooner:

Low Carbohydrate Diet From Plant or Animal Sources and Mortality Among Myocardial Infarction Survivors, Journal of the American Heart Association, 22 September 2014

Researchers analyzed data from 2258 women who took part in the Nurses’ Health Study and 1840 men from the Health Professional Follow‐Up Study. All had survived a first heart attack.

There was an increased risk both to those who started eating low-carb before their heart attack, and to those who changed to eating low-carb after their heart attack:

Eating low-carb all along:

• 33% higher risk for death from any cause
• 51% higher risk for cardiovascular-related death

Increased low-carb eating after heart attack:

• 33% higher risk for death from any cause
• 53% higher risk for cardiovascular-related death

What were low-carbers eating?

“Participants with the highest total LCDSs [low-carb diet scores] had greater intake of red meat and high‐fat diary and less consumption of dietary fiber.”

They pointed a finger at saturated fat:

“In our analyses, associations with animal‐based LCDs were attenuated after additionally adjusting for saturated fat intake. This suggests that the higher mortality may be due, in part, to saturated fat intake in the animal‐based LCDs.”

The weird thing is, they went into this study assuming a low-carb diet would prevent heart attacks. Instead, they found it promoted them:

“We hypothesized that greater adherence to an LCD in the period following MI is associated with lower mortality.”

Low-carb diets assist weight loss in the short-term. But there is not a lot of investigation into the diet’s long-term effects. It may turn out that people eating low-carb die earlier with better numbers.