(RxWiki News) For years, people have heard they should not eat saturated fat. This kind of fat is found in butter, cheese, meats and other heavier foods. But the wisdom of that advice may be changing.
A recent research analysis found that a high intake of saturated fat did not actually appear to be linked to an early risk of death, even from heart disease or cancer.
A slightly higher risk of death, including from heart disease, did exist for high intakes of meat.
But cheese, butter and other dairy products high in saturated fat seemed to have no impact on a person's risk of death.
"Ask your family doctor about a healthy diet."
This study, led by Therese O'Sullivan, PhD, of the School of Exercise and Health Science at Edith Cowan University in Western Australia, looked at whether saturated fat intake was related to a person's likelihood of dying.
The researchers looked for all studies between 1952 and 2012 in four major medical research databases related to consumption of foods high in saturated fat and risk of death.
They identified 26 studies that had sufficient data on the participants' diets and included statistics on the participants' deaths by cancer, cardiovascular problems or any cause at all.
The types of foods the researchers looked for in studies included dairy products, meat products, oils, chocolate, lard, butter and cheese.
The two countries who produced the most studies were the US, where 12 studies had originated, and Japan, where seven had originated. The researchers analyzed all the data from all 26 studies together.
The number of participants in the studies varied from 162 participants to 764,343 participants. Follow-up time ranged from five years to 41 years.
The researchers found that individuals who ate high amounts of milk, cheese, yogurt or butter were at no higher risk for death than those who ate small amounts of these foods.
Eating high amounts of meat and processed meat, meanwhile, was linked to a higher risk of death in most studies.
A high intake of meat in general was linked to a 17 percent greater risk of death. A high intake of processed meat was linked to a 21 percent greater risk of death.
Meat and processed meat intake were also linked to a slightly higher risk of death from cancer or from cardiovascular disease.
However, in extracting data from the studies, the researchers wrote that they primarily included data from red meat when the data included different meat options.
The quality of the studies included varied considerably in terms of how long the researchers' follow-up period was, how they collected data on participants' diets and what other non-diet factors the researchers took into account that might also influence a participants' risk of death.
"Early guidelines regarding intake of saturated fat, which remain largely unchanged today, lacked a strong evidence base," the authors wrote.
The authors explained that these guidelines had come from researchers' assumptions about the way cardiovascular diseases were caused.
Researchers previously believed that eating unsaturated fats instead of saturated fats would lower individuals' total cholesterol levels and therefore reduce their risk of heart disease.
"This is now thought to be an oversimplification of the multiple processes that influence the impact of dietary composition on human health," the researchers wrote. "Our review is unable to support a strong recommendation regarding restricting intake of foods high in saturated fat for the prevention of mortality."
This study is a welcome confirmation that past guidelines have led consumers astray, according to Deborah Gordon, MD, a dailyRx expert who specializes in nutrition.
"As a nation we have followed those assumptions down a long and winding road of increasing obesity, diabetes and cardiovascular disease as we have eschewed saturated fat and replaced it with its poor cousin: sugary or deep-fried carbohydrates," Dr. Gordon said.
"The authors have provided a valuable tool as nutritionally-minded health providers work to undo the damage that has been done," she said. "Their work is only a start, however."
Dr. Gordon said more needs to be done to educate consumers about what constitutes a truly healthy diet.
"We will make significant improvements in our general and individual health only with a major overhaul of dietary guidelines and the consumption patterns they influence," she said. "This study is a wonderful contribution to the major overhaul."
"We can assure people to limit their processed meat, but to feel comfortable eating red meat and dairy fat as they will not increase their mortality or risk of cardiovascular disease," Dr. Gordon said.
"Yet our current risks of cardiovascular disease, cancer and obesity-associated morbidity are not acceptable risks," she said. "We will have to turn far from the guidelines of recent decades toward consumption of sustainably-raised real and unprocessed foods before we reduce disease and death risks."
This study was published July 18 in the American Journal of Public Health.
The research was funded by the National Health and Medical Council.
One author has previously received a Dairy Innovation Australia grant for a different study.