Trans fats are definitely bad; saturated fat, maybe not so much, say researchers who suggest a reasonable amount of saturated fat in a person's diet may not have associations with health risks.
The same can't be said for trans fats, according to Canadian researchers who reviewed a number of studies; they are associated with increased risk of death from a number of causes, including cardiovascular disease and coronary heart disease.
Saturated fats are found in many dairy products and meat; trans fats are more commonly found in highly processed foods such as margarine, baked goods and snack foods.
"Not all the studies we looked at reached the same conclusion, but generally what we found is that the association between a higher consumption of trans fats and a higher risk for heart disease and [early] death was very consistent," says study author Russell de Souza, a dietitian and professor at McMaster University in Ontario.
Those same studies suggest no similar association between consuming saturated fat and a higher risk for similar health issues, the researchers said, although de Souza counsels caution. He iterates that there is no proof that saturated fat is completely risk-free.
The analysis of a total of 41 studies of saturated fats conducted in countries that include the United States, Canada, the United Kingdom, Sweden, Japan and others has been published in the British Medical Journal.
It also contained an examination of 20 trans fats studies from the United States, China, the Netherlands and Finland.
Most researchers agree on the risks posed by trans fats, and in the U.S., the Food and Drug Administration has given food manufacturers until 2018 to remove foods with trans fats from the nation's supermarket shelves.
There is no similar agreement on saturated fats as yet, and some experts cautioned against taking the latest analysis as declaring them risk-free as compared with trans fats.
"Trans fat remains a definite concern," says Lona Sandon, an assistant professor of clinical nutrition at the University of Texas. "Saturated fats are a little up in the air."
Part of the problem, she notes, is that some saturated fats have been found to be not harmful and possibly even beneficial.
"However, you cannot separate out the healthy types of saturated fats from those that are not so healthy," she explains. "They come packaged together in foods."
