Back in the 1980s and 90s, low-fat diets were trendier than paleo, keto and Whole30 diets combined. Open up any lifestyle magazine and you’d find low-fat recipes and weight-loss success stories. The reasoning — that less fat in your food would translate to less fat in your body — seemed intuitive. And the idea that you could eat any food, and as much as you wanted, as long as it was low-fat or nonfat, was irresistible.
Inevitably, a slew of products marketed as non- or low-fat hit grocery store shelves. Middle-aged adults may recall gorging on entire packages of fat-free cookies or large bags of pretzels because, hey, it’s OK, the fat content is low. However, it became clear that calories still counted for losing weight and good nutrition really mattered for staying healthy.
Eventually, although they didn’t disappear, the Pritikin diet and other low-fat plans with a lot of buzz faded in popularity. Even so, low-fat plans that focus on nutritious foods can work well. Here’s what healthy low-fat eating looks like today.
What makes a diet qualify as low-fat?
“A well-accepted definition of a low-fat diet is one in which no more than 30 percent of calories come from fat,” says Jill Weisenberger, a Virginia-based registered dietitian nutritionist and author of “Prediabetes: A Complete Guide.” However, the fat content is much lower in certain plans, she points out.
“Usually, the range you see is 20 to 30 percent fat,” says Carrie Dennett, a Seattle-based registered dietitian nutritionist. “There’s no consistent range.”
What are some popular low-fat diets?
A breakdown of nutritional content for a typical day’s meals is provided for every plan in U.S. News Best Diets. Ornish and TLC (Therapeutic Lifestyle Changes) are two top diets identifying themselves as low-fat. Two Ornish versions (16 percent or 11 percent fat), TLC (22 percent fat), Macrobiotic (17 percent fat) and Engine 2 (23 percent fat) clearly fall into the low-fat category. Among these, the Engine 2 and Ornish, in particular, perform well as weight loss diets.
Other ranked plans that aren’t necessarily focused on low-fat food still fall into an at least lower-fat range. Versions of the Mayo Clinic Diet have a fat content of 22 percent, as does Jenny Craig. Fat content for Volumetrics comes in at 24 percent. Biggest Loser has a fat content of 25 percent.
Two DASH (Dietary Approaches to Stop Hypertension) versions have a total fat content of 26 and 27 percent. Two Nutritarian versions are 26 or 29 percent, respectively. Flexitarian is 27 percent fat, while Mediterranean fat content is 29 percent.
What are health benefits of low-fat diets?
People may follow low-fat diets for medical reasons. Digestive disorders such as gastroparesis or gallbladder disease are diagnoses for which low-fat plans are recommended, Weisenberger says. In these conditions, the body is less able to break down or absorb fatty foods. In other cases, eating fatty foods can aggravate diarrhea.
Heart disease prevention is another medical reason to choose a low-fat eating plan. The Ornish diet was created by a physician, Dr. Dean Ornish, founder of the Preventive Research Medicine Institute in Sausalito, California. On Ornish, whole-grain foods such as whole-grain bread or quinoa spaghetti replace refined carbs such as pasta and white bread. Veggies and fruits are emphasized. Low-fat or nonfat dairy replace full-fat dairy.
If you’re looking to reduce your intake of saturated and trans unsaturated fat, Ornish could be an excellent choice. Only 2 percent of calories come from saturated fat and the trans fat content is zero.
Among U.S. News Best Heart-Healthy Diets, Ornish made the top spot in 2019, tying for first place with Mediterranean. A study of heart disease patients found the Ornish program reverses artery blockage. Other research shows that Ornish eating can help lower blood pressure and reduce “bad” LDL cholesterol and total cholesterol.
The TLC diet is ranked No. 4 in Best Heart-Healthy Diets. It was created by the National Cholesterol Education Program, an initiative of the National Institutes of Health, to reduce cholesterol as part of a heart-healthy eating plan. The broad TLC guidelines center on foods such as fruits and vegetables, breads, cereals, pasta and lean meats.
Several studies show that people who followed TLC reduced their blood levels of total cholesterol, LDL cholesterol and triglycerides. The TLC eating pattern is considered safe for children as well as adults, and is sometimes prescribed to kids who develop Type 2 diabetes or high cholesterol.
[See: U.S. News Best Diets Overall.]
Overall, plant-based plans are considered heart-healthy. Macrobiotic diets, which have been around for centuries in many variations, are basically vegetarian, with some nearly vegan. The focus is on natural, organic, locally grown whole foods. There’s a strong philosophical aspect to macrobiotic plans, with some incorporating Buddhism or meditation, and stricter versions discourage cooking with electric stoves or microwaves.
Engine 2 is a low-fat, high-plant diet similar to vegan eating. Engine 2 eliminates vegetable oils and encourages whole plant foods. Whole, intact grains, fruits, vegetables and legumes are Engine 2 staples. Following Engine 2 will definitely limit your total intake of fats and oils.
Low-fat diets may play a role in cancer prevention. A low-fat regimen was associated with reduced incidence of pancreatic cancer in overweight or obese women, according to a large study in the January 2018 issue of the Journal of the National Cancer Institute.
Among older women diagnosed with breast cancer, those who followed a low-fat plan afterward were more likely to be alive 10 years after diagnosis, compared to women who followed a higher-fat plan, according to a study published online in May of 2018 in JAMA Oncology.
Low-fat or low-carb for weight loss?
Whether low-fat or low-carbohydrate diets — such as paleo or Atkins — work better for weight loss is a long-running dietary debate. Recent evidence suggests it’s actually a toss-up between the two.
A study published in the Journal of the American Medical Association in February 2018, pitted a healthy low-fat diet against a healthy low-carb diet. About 610 overweight participants were randomly assigned to follow one or the other over a year. The difference in weight loss was not considered significant, with the low-fat group losing an average of nearly 12 pounds compared with 13 pounds for the low-carb group.
“Low-carb diets usually result in greater weight loss in the first few months,” Weisenberger says. “So, if you follow people for three months to six months (on) either a low-carb or a low-fat diet, it does look like the people on the low-carb diet are losing more weight. But if you follow them out to a year or two, or longer, the weight loss is about the same. There’s a faster initial weight loss but not a greater overall weight loss.”
[See: How to Stop Emotional Eating.]
Trim fat naturally.
Ultimately, the best eating plans focus on food quality versus fat content alone — or the content of any single food group or nutrient — experts agree. Choosing naturally low-fat foods — like a fresh fruit instead of a sugar-free cookie — is a healthy way to cut fat. These swaps cut your sugar intake without neglecting healthy nutrients such as potassium, vitamin C, dietary fiber and folic acid.
Simple changes can easily reduce the fat you consume. Trimming fat helps. When you remove all or some of the fat from dairy foods or from meat, like using 90 percent lean ground beef instead of 80 percent lean ground beef, or you remove chicken skin, you’re also reducing the calories significantly, Weisenberger says. That’s another plus for people managing their weight.
Tweaking how you cook also helps. “Maybe you’re steaming your vegetables instead of roasting them in olive oil,” Dennett says. “And you’re eating lean cuts of meat, and fruits and beans and not adding a lot of fat.”
What works for you?
Some people naturally gravitate to a low-fat diet, just as others are drawn to a low-carb plan, Dennett says. If you’re more comfortable cutting fat than tightly limiting carbs, low-fat might be right for you. Find out what suits you best and aim for healthy, high-quality food in whatever eating plan you choose, she suggests.
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