Eat Fat, Be Fit
New research suggests butter, beef, and bacon might not be so bad after all. What’s their place in a healthy runner’s diet?
Runners like to follow the rules. And for decades, nutrition rules put a strict limit on saturated fat. After all, as far back as the 1960s, experts have decreed that eating foods high in saturated fat, such as eggs, red meat, and full-fat dairy, will increase your risk of heart disease. So runners took heed, all but banishing those foods from their diets.
But a string of news-making studies has flipped that idea on its head. One of those headline-catchers, published in the Annals of Internal Medicine early last year, reviewed 76 existing studies and found no association between saturated fat and heart disease. Another earlier study review published in 2010 came to a similar conclusion. The new emerging thought: “Saturated fat may not be the demon that it was made out to be,” says Jeff Volek, Ph.D., R.D., associate professor in the department of kinesiology at the University of Connecticut.
Before you go celebrate this news with a round of bacon cheeseburgers, there’s a catch. Just because these study reviews didn’t find an association doesn’t mean there isn’t one. Many of these studies were observational–meaning, they were not designed to find direct cause and effect. They also rely on participants to self-report their diets, and often, these reports can be inaccurate.
What researchers do know through randomized, controlled clinical studies–the gold standard of research methods–is this: “Saturated fat raises LDL levels,” says Penny Kris-Etherton, Ph.D., R.D., distinguished professor of nutrition at Penn State University. Because LDL can contribute to plaque deposits in arteries, “it is one of the two major risk factors for cardiovascular disease.” Kris-Etherton goes on to explain that when you substitute “good” polyunsaturated fats (found in fish and vegetable oils, such as canola) for saturated fat, LDL levels go down and so do incidences of heart disease. The evidence for this is found in study after study.
There are other reasons to avoid going hog-wild on saturated fat: High-fat diets have been linked to some cancers, and processed meats like bacon and sausage may increase diabetes risk. That’s why the American Heart Association recently updated its guidelines–the group recommends limiting saturated fat to five or six percent (down from its previous target of seven percent) of total calories–or about 11 to 13 grams a day on a 2,000-calorie diet.
While all that might seem to squash any hope of welcoming butter back into your diet, it’s not all bad news. Saturated fat actually boasts some benefits. For example, certain medium-chain saturated fats, like lauric acid (plentiful in coconut oil), have the potential to be immediately burned for energy rather than stored. Besides, taking out saturated fat has a strange effect: It lowers levels of the so-called “good cholesterol,” HDL, which sweeps LDL out of the bloodstream. “What the research comes down to is that all foods fit into a healthy diet–in moderation,” says sports dietitian Heather Fink, R.D. “Runners are active and health conscious, so they’re prone to restricting those foods. They don’t have to,” she says. It’s about looking at the total food versus a single nutrient. Some foods higher in saturated fat are really nutritious–and excluding them means you miss out. For example, red meat contains iron, zinc, and protein. Whole milk is an excellent source of bone-building calcium and vitamin D, two nutrients many runners fall short on. Grass-fed beef and dairy also provide conjugated linoleic acids, which have been linked to weight loss. Besides, there’s a “yumminess” factor (and yes, that counts for something). Full-fat foods are more flavorful and satisfying, which can reduce your appetite, says Volek.
A varied diet that incorporates natural whole foods–including some sources of saturated fat–can supply a range of nutrients that keep you in top running form and health. So go ahead. Enjoy that chicken thigh with the skin. Spread some butter (the real stuff!) on your toast. Add a slice of cheddar to your sandwich. As long as you’re first reaching for plenty of vegetables, fruits, whole grains, and lean protein, you’ll be doing your body–and your running–good.
Eggs: They’re rich in choline, a nutrient that plays a key role in memory. (2 g sat. fat per egg)
Chicken thigh: Dark meat is high in immune-boosting zinc. (3 g sat. fat per thigh)
Macadamia nuts: One ounce has 60 percent of your daily quota for manganese. (3 g sat. fat per ounce)
Red meat: It’s a good source of energy-supplying B12. (3 g sat. fat per 3.5 ounces)
Whole-milk yogurt: It’s full of probiotics linked to weight loss. (5 g sat. fat per cup)
Cheddar cheese: A slice packs 20 percent of daily calcium needs. (6 g sat. fat per ounce)
Coconut oil: It contains fat that has the potential to be burned quickly. (12 g sat. fat per tablespoon)