A recent study linked eating more saturated fat with a lower mortality rate. If that sounds like it conflicts with everything you thought was true, here's what you should know.

By Renee Cherry
September 10, 2018
Photo: Arnold Zabert / Getty Images

Saturated fats bring out some strong opinions. (Just Google "coconut oil pure poison" and you'll see.) There's a constant back and forth on whether they're actually all that unhealthy. While conventional wisdom says to limit saturated fat, a recent study has many people questioning whether it deserves its bad rap. The Prospective Urban Rural Epidemiology (PURE) study published in The Lancet found an association between eating saturated fat and living longer. (Related: Is Red Meat *Really* Bad for You?)

Here's what went down: More than 135,000 people from 21 different countries answered food questionnaires about their diets over the course of seven years. Researchers recorded how many subjects died from heart disease, stroke, or another cause. They looked at how total fat intake, and intake of one of three types of fat (monounsaturated, saturated, polyunsaturated) related to mortality. In each case (including saturated fat) eating more of the particular type of fat was associated with lower mortality. Higher saturated fat intake was associated with a lower stroke risk-another point for team sat fat.

Quick refresher: Saturated fats mainly come from animal-based foods. The main gripe with saturated fats is that they have been shown to raise LDL (bad) cholesterol levels. But it's not all black and white. For one thing, there's a huge ongoing debate centered around coconut oil, since it's high in saturated fat but also contains medium-chain triglycerides, which the body can quickly burn for fuel. To further confuse things, one study suggests that eating saturated fats from dairy lowers your risk of cardiovascular disease, while eating saturated fats from meat raises your risk. (Related: Healthy High-Fat Keto Foods Anyone Can Add to Their Diet)

The dietary guidelines in the U.S. side with the thought that you should limit saturated fats in favor of monounsaturated and polyunsaturated fats. The USDA recommends consuming less than 10 percent of calories per day from saturated fats. Say you eat 2,000 calories in a day. That would mean eating 20 grams or less of saturated fat per day. The American Heart Association recommends getting even stricter, with no more than 6 percent of calories from saturated fat per day. That's about 13 grams for a 2,000 calorie diet-the amount found in about 1 tablespoon of coconut oil. According to the PURE study authors, their findings are in line with existing research suggesting that in other countries where nutrition patterns are different, there's no need to be so restrictive. "Current guidelines recommend a low-fat diet (< 30 percent of energy) and limiting saturated fatty acids to less than 10 percent of energy intake by replacing them with unsaturated fatty acids," they wrote. But these recommendations are based on U.S. and European countries where malnutrition isn't a concern. Rather, eating certain nutrients in excess is a factor. So, while adding more fat of any kind could be beneficial to those in undernourished populations, the same might not be true in the U.S.

Most headlines about the PURE study have been along the lines of Red Meat and Cheese Are Actually Good, Guys! But these results shouldn't be taken as definitive proof that the U.S. dietary guidelines need to change, says Taylor Wallace, Ph.D., professor at George Mason University. "I'm kind of wary about saying 30 percent of fat in your diet is OK. I think that we've seen that the type of fat really matters," says Wallace. "I would definitely recommend trying to reduce the amount of saturated fat you get in your diet because we know that high intake of saturated fat can raise your bad cholesterol." In other words, all fats are not created equal. (Here's why it's important to get enough healthy fats.)

So why was more saturated fat associated with a longer life? For one thing, there are plenty of benefits that have been connected to including meat and dairy in your diet. "Dairy is providing your calcium, vitamin D, magnesium, and protein, and red meat is providing a lot of protein and different vitamins and minerals that are all important for bone health," says Wallace. Plus, as the study authors pointed out, adding more saturated fats can have a different result in different areas. "If you look at low-income areas of the world, malnutrition from an inadequate food supply is very prevalent," says Wallace. "If you give a starving population full-fat dairy or unprocessed meat, you would lower the risk of mortality in that population just because you are giving starving people the calories they need to survive." You won't necessarily have the same positive effect in a nourished population.

Once again, the pros and cons of saturated fat prove to be complicated. Sorry, ribeye lovers-this study doesn't suggest that you should ease up on restricting saturated fat, but it might suggest that guidelines established in one country shouldn't necessarily be applied everywhere.