Eggs are in. Eggs are out. Healthy fats are in. Transfats are out. As research evolves about how diet affects our health—and different recommendations seem to come out every week—it can be hard to know what to believe anymore.
“We've been told for decades that eating a low-fat diet is helpful for heart disease and stroke prevention," says Dr. Brad Jacobs, MD, and chair of Pharmaca's Integrative Health Advisory Board. "It turns out we were wrong. Now, a lot of the data is showing that a low-fat diet is no better for us, and can actually lead to more weight gain and more risk of stroke, diabetes, heart disease." The rationale is people on a low fat diet typically replace fat calories with carbohydrates (grains, bread, pasta) which causes surging levels of sugar in the body, inflammation and even more hunger.
Dr. Jacobs cites three studies published this year that show that low-fat diets aren’t doing us any good. “The thought is that certain types of fatty acids are actually helpful—like the polyunsaturated and monounsaturated fats that you find in avocados, olive oil, nuts and fish oils.”
First, the body needs fat and cholesterol to help our brains form the myelin sheaths that protect our neurons, says Dr. Jacobs. He adds that fat is also vital to many of our body’s cellular processes. In addition, new research is showing that saturated fats, like those found in vegetable and dairy products, can help increase the good part of our low-density lipoprotein cholesterol (LDL, normally thought of as the “bad” cholesterol).
Yup, LDL isn’t all bad news. LDL is actually made up of two different types of cholesterol: type A, the lighter, bigger cholesterol particles, and type B, which are smaller and more dense. Type B is the one linked to health problems, and is the one that increases when we eat too many simple carbohydrates. Type A, on the other hand, seems to increase through intake of fat.
Cholesterol aside, Dr. Jacobs says, there are a few other reasons why low-fat diets can stifle weight loss efforts and create other health problems as a result. “When you go on a low-fat diet, you have to replace those calories with something—either with more protein or more carbs,” he says. “Fat makes you feel satisfied and full, so low-fat diets may cause you to eat more calories because your brain never registers that feeling of satisfaction.”
Finally, foods that are marketed as “low fat” are often filled with salt and sugar to make up for the absence of fat. Make sure you’re reading labels, Dr. Jacobs says, to ensure there’s not a lot of other bad stuff in place of fat.
To make sense of it all, Dr. Jacobs offers these good eating rules of thumb.
Fill your plate first with vegetables. “Vegetables are good for you in abundance because they have lots of fiber, and lots of anti-inflammatory and antioxidant nutrients,” he says. “Studies show that if you eat seven servings of vegetables each day, you reduce your chance of dying from heart disease, cancer and all other causes of mortality of by 42 percent! Even if you can’t get in seven, every serving helps lower that risk.”
Make sure refined carbohydrates don’t take up more than one-quarter of your daily calorie intake. For a woman on a typical 2,000 calorie diet, that means no more than 500 calories, or 125 g. And, says Dr. Jacobs, “You want carbs that take a long time for your body to digest, so the sugar enters your bloodstream slowly rather than all at once. Simple carbs immediately get converted into sugar and increase your insulin levels.” That throws your blood sugar out of whack, and can affect our energy and hunger levels—and make it hard to eat healthy.
Limit saturated fat from animals. The European Perspective Investigations into Cancer (EPIC) study showed that consumption of more than 8 oz of red meat—especially processed meats—lead to a greater incidence of cancer and death. So, while your body needs a little saturated fat now and then, the emphasis is on a little.
Choose healthy sources of fats. Dr. Jacobs recommends avocado, fish, nuts and nut oils, olive oil and coconut oil as the best place to get the fat your body needs to feel full and perform best.