You likely know that a fatty diet is bad for you, but that may all depend on what kind of fats you're talking about.
A new study from Canada found that trans fats may be linked to an increased risk of both heart disease and death. Saturated fats, however, may not be linked to either or to an increased risk of stroke or type 2 diabetes.
"For years everyone has been advised to cut out fats," said lead study author and dietitian Russell de Souza, RD, ScD, an assistant professor of epidemiology at McMaster University in Ontario, Canada, in a press release. "Trans fats have no health benefits and pose a significant risk for heart disease, but the case for saturated fat is less clear."
Gabriela Pichardo-Lafontaine, MD, an internist at Scott and White Healthcare in Round Rock, TX, explained why saturated fats aren't necessarily bad, despite what the public may have been told about them.
"Your body needs some fat from food," Dr. Pichardo-Lafontaine told dailyRx News. "It’s a major source of energy. Saturated fats from animal and vegetable sources provide a number of important health benefits. In fact, your body cannot function without saturated fats."
According to Dr. de Souza, current dietary guidelines recommend limiting trans fats to less than 1 percent and saturated fats to less than 10 percent of the total number of calories consumed daily.
Saturated fats are found in many animal products, including butter, cows' milk, meat, salmon and egg yolks. Palm oils and chocolate also contain saturated fats.
Trans fats, however, are industrially produced from plant oils in a process known as hydrogenation. They are typically found in margarine, snack foods and packaged baked goods.
Dr. de Souza and team looked at 50 studies on the topic to determine the link between fat types and health outcomes in US adults.
No link was found between a high intake of saturated fat and death from all causes, or between saturated fat and heart disease, stroke or type 2 diabetes.
The picture was very different for trans fats, however.
A high intake of trans fats was linked to a 34 percent increased risk of death from all causes, a 21 percent increased risk of developing heart disease and a 28 percent increased risk of death from heart disease.
No link was found between trans fats and type 2 diabetes or stroke.
"Many have now realized that it's the trans fat found in margarine, vegetable shortening, and partially hydrogenated vegetable oils that is the true villain, causing far more significant health problems than saturated fat ever could," Dr. Pichardo-Lafontaine said.
Dr. Pichardo-Lafontaine recommends a balanced diet consisting of grains, fruits, vegetables, proteins, dairy and even some fats to reduce the risk of heart disease, stroke and type 2 diabetes.
This study was published in the August issue of the BMJ.
The World Health Organization funded this research. No conflicts of interest were disclosed.