Low-Fat Diets Are Not the Most Effective for Weight Loss

Low-fat yogurt, low-fat dressing, low-fat muffins… if you’re trying to lose weight, these foods might seem like they should make up a huge portion of your diet. Less fat means fewer calories, and consuming fewer calories leads to weight loss, right?

It turns out, that’s not entirely true.

Why a Low-Fat Diet Isn’t Best for Weight Loss

For years, nutritionists touted the benefits of a low-fat diet, or consuming 20 to 30 percent of your daily calories from fat. But a recent study found that low-fat diets may not be the most effective way to lose weight.

“Fat contains more than twice the number of calories than carbohydrates and protein, so it has naturally been a target [for weight loss], but this message is ineffective,” Dr. Deirdre Tobias explains. “Taking the focus off of total fat, and shifting to achieving an overall healthy, high-quality diet may be the ideal strategy for long-term weight-loss success.”

Dr. Tobias worked on a team with researchers from Brigham and Women’s Hospital and the Harvard T.H. Chan School of Public Health to examine a variety of weight-loss strategies. Among the trials that were reviewed, the team discovered that both high-fat diets and low-carbohydrate diets led to significantly greater weight loss than low-fat diets.

“A low-fat diet may lead people to avoid several choices for healthy high-fat foods, like nuts, vegetable oils, and avocados. It can give too much leeway to make poor choices, like opting for processed foods, refined grains, and sugar,” Tobias explains.

Know Your Fats

So what kinds of fats should you go for? “The majority of fats that come from minimally processed whole foods are good for us in moderate quantities,” says Andy De Santis, RD, and a nutrition blogger from Toronto, Canada. “Most of the foods that contain these types of fats also contain a variety of other very healthy compounds, vitamins and minerals.”

The “good” fats DeSantis refers to include both monounsaturated and polyunsaturated fatty acids. These are most noted for their role in heart health. Replacing less healthy fats, such as saturated and trans fats, with these unsaturated fats from whole-food sources, may offer several health benefits.

The “good” fats De Santis refers to include monounsaturated fatty acids, which like all fats, help your body absorb fat-soluble vitamins A, D, E, and K. Polyunsaturated fats include omega 3 and omega 6 fatty acids. When consumed in a healthy ratio, these fatty acids can help support healthy cholesterol and blood pressure levels, and may reduce your risk of various chronic conditions.

Some of the best sources of these fats are fatty fish like salmon, herring, and mackerel, avocados, whole eggs, olive oil, safflower oil, avocados and avocado oil, pistachios, almonds, walnuts, flaxseed, and olives.

“These types of fats are strongly linked with health benefits and positive health outcomes and the fats most of us should strive to consume more of,” says De Santis.

The Dietary Guidelines for Americans 2015–2020 recommend that about one in every four calories* should come from fats to ensure the body gets enough of those fat-soluble vitamins — preferably from healthy fats.

(*total fat intake is 25 to 35 percent of calories (1 in 4) for most age groups).

Skip Saturated Fat (Mostly)

Even though healthy fats aren’t the enemy, many experts feel there are some kinds of fats that should be avoided — especially the man-made trans fats linked to an increased risk of heart disease. “Saturated fats are linked to poor heart health outcomes, and should be limited,” Dr. Tobias says. “Choosing low- and reduced-fat dairy products and limited red and processed meats will cut back a significant amount of saturated fat in your diet.”

That’s not to say you have to avoid saturated fat all together. “You should aim for no more than 10 percent of your caloric intake to be derived from saturated fats,” says De Santis. “So, if you are consuming 2,000 calories a day, that equals to 22 grams of saturated fat daily.”

The key is to be mindful when it comes to choosing the types of food you eat. So while you may want to skip that packaged donut or greasy slice of pizza, you can opt to cook with coconut oil — made up of about 90 percent saturated fat — which may boost levels of good cholesterol.

Losing Weight Without Going Low Fat

So how do you strike the best balance when it comes to how much fat you consume? “The safest and smartest way to lose weight and maintain the loss is to make slight reductions of your food intake across all of the macronutrients,” says De Santis.

“Theoretically, this can be as simple as cutting out that 500 calorie Starbucks drink they have every day. For others, it may involve slightly reducing portion sizes at meals. Essentially, you need to consume slightly fewer calories than you were before in order to lose weight.”

Instead of obsessing over exact calories, an effective and long-term weight loss plan should focus on a well-rounded diet. You should aim for a diet rich in whole grains, fruits, and especially vegetables. For protein, chicken, eggs, and fish are great options, as are plant-based sources like quinoa, hemp, tofu, tempeh, and the combination of whole grains and legumes.

Be Smart About Your Weight Loss

Granted, everyone’s path to weight loss is an individual journey. But there are some basic best practices we all can apply to our daily lives, primarily focusing on filling up on whole, healthy foods, being aware of portion sizes and getting plenty of regular exercise. And, stresses De Santis, don’t restrict food from your diet just because it has fat in it.

“Weight-loss solutions differ greatly based on the way a person eats,” he says. “But it is never wise to eliminate healthy foods from your diet just because they contain fat, especially from healthy sources.”

Low-fat yogurt, low-fat dressing, low-fat muffins…if you’re trying to lose weight, these foods might seem like they should make up a huge portion of your diet. Less fat means fewer calories, and consuming fewer calories leads to weight loss, right?

It turns out, that’s not entirely true.

Why a Low-Fat Diet Isn’t Best for Weight Loss

A recent study published in The Lancet Diabetes & Endocrinology found that low-fat diets aren’t the most effective for weight loss.

Dr. Tobias worked on a team with researchers from Brigham and Women’s Hospital and the Harvard T.H. Chan School of Public Health to examine a variety of weight loss strategies. Among the trials that were reviewed, the team discovered that both high-fat diets and low-carbohydrate diets led to significantly greater weight loss than low-fat diets. Tobias explains, “A low-fat diet may lead people to avoid several choices for healthy high-fat foods, like nuts, vegetable oils, and avocados. It can give too much leeway to make poor choices, like opting for processed foods, refined grains, and sugar.”

Even though healthy fats aren’t the enemy, many experts feel there are some kinds of fats that should be avoided. “Saturated fats are linked to poor heart health outcomes, and should be limited,” Dr. Tobias says. “Choosing low- and reduced-fat dairy products and limited red and processed meats will cut back a significant amount of saturated fat in your diet.”

Instead of obsessing over exact calories and specific amounts of fats, carbohydrates and protein, an effective and long-term weight loss plan should focus on a well-rounded diet. You should aim for a diet rich in whole grains, fruits, and especially vegetables. For protein, chicken, eggs, and fish are great options, as are plant-based sources like quinoa, hemp, tofu, tempeh, and the combination of whole grains and legumes. Don’t worry so much about labels. Instead, think more about eating foods and you won’t even have to give a second glance to products with labels such as “low-fat,” “high-fiber,” etc.