Food fight about butter? Study says subbing in plant-based oils could reduce risk of death

The study, published on Thursday in JAMA Internal Medicine, revealed that "substituting butter with plant-based oils, particularly olive, soybean and canola oils, may confer substantial benefits for preventing premature deaths."

Using data collected from three cohort studies spanning 33 years, researchers assessed diets from "food frequency questionnaires" done every four years.

The study was done by the Department of Epidemiology at the Harvard T.H. Chan School of Public Health in Boston along with other Boston institutions. The Department of Public Health at the University of Copenhagen in Denmark also took part.

Total mortality was the primary outcome, and mortality due to cancer and CVD were secondary outcomes, the study said.

"Deaths were identified through systematic searches of state vital records and the National Death Index, supplemented by reports from next of kin and postal authorities," the study noted. "Using these methods, we achieved more than 98% completeness in mortality follow-up for the cohorts."

Lauren Manaker, a registered dietitian in South Carolina, told Fox News Digital she's not surprised by the study results.

"We are already aware that consuming excessive amounts of saturated fats is not something that supports our health - and butter is a source of saturated fat," said Manaker, who was not involved in the new research. 

But chef Andrew Gruel, who owns the American Gravy restaurant group in California, recently told Fox News Digital that he believes butter is better than it's perceived.

"The idea that butter is inherently bad for you comes from outdated dietary advice rooted in the mid-20th century push against saturated fats," Gruel said.

Gruel added, "Butter's saturated fat - about 7 grams per tablespoon - does raise LDL ('bad') cholesterol, but it also raises HDL ('good') cholesterol, which can offset some of the risk. Plus, not all LDL is created equal."

He said, "Butter increases the more significant, less harmful LDL particles than small, dense ones tied to artery clogging."

"If you want to have a heart attack, that's the right step to take," Willett, who co-authored the new study, told Fox News Digital.

Willett also said the idea that seed oils are bad "is a complete myth."

"There's no evidence to support that," he said.

Willett pointed out that it's worth noting the new study doesn't mean "somebody should never use butter."

"What we're really talking about is what people do on a daily basis," he said.

Manaker agreed with that.

"This doesn't mean that you have to avoid butter like it's poison," she said.