Why We Should All Stop Tracking Our Dietary Fat Intake, According to RDs

Most of us have probably lived through enough diet-related trends to realize that there's reason to be wary when an entire food group gets demonized. Fat is a perfect example. For years, no- and low-fat everything was being touted as the healthiest possible option. But we've got news for you: fats are an important part of a healthy diet. Not only do they keep you full, but they also play a huge role in keeping your whole body (and brain) in good working order. If you're curious about how much fat you should be aiming for each day, we're here to help. (Though, spoiler alert, you probably don't need to worry about counting it.)

To find out exactly how much fat you should be eating per day, PS spoke to Avigdor Arad, PhD, RDN, CDE, the director of nutrition and physiology at the Tel Aviv Sourasky Medical Center and the former director of the Mount Sinai Physiolab. According to Dr. Arad, the limit does not exist — well, kind of.

"What we know is that what's more important is the type of fat we're eating, and not so much the quantity," he tells PS. "As long as you stay within a normal, healthy calorie load, and you're a person who can process and metabolize and use fat very effectively, then you can eat a lot of fat as long as it's the healthy kind of fat." What does that mean for you? Let's break it down.

Avigdor Arad, PhD, RDN, CDE, the director of nutrition and physiology at the Tel Aviv Sourasky Medical Center and the former director of the Mount Sinai Physiolab.

To help you remain within a "healthy calorie load," as Dr. Arad says, and leave room in your diet for other nutrients (including two other important macronutrients: protein and carbs), the World Health Organization (WHO) recommends adults limit their total fat intake to 30 percent of their total calorie consumption or less. For example, if you're eating about 2,000 calories per day, that means you should get a maximum of 600 calories from fat each day. Because there are nine calories in each gram of fat, that equates to about 67 grams of fat.

In their most recent guidelines, the WHO also set recommended maximums for two types of fats: saturated fat and trans fat. The organization says no more than 10 percent of total calorie intake should come from saturated fats (i.e. 200 calories in a 2,000-calorie-per-day diet) and no more than 1 percent of total energy intake from trans fats (i.e. 20 calories in a 2,000-calorie-per-day diet).

To understand how much fat you should eat per day, it helps to be familiar with the different types of fats.

Mono- and polyunsaturated fats: Monounsaturated fats (found in nuts, avocados, and vegetable oils) and polyunsaturated fats (found in salmon and walnuts) are considered "healthy fats," according to Dr. Arad. (One type of polyunsaturated fats you've likely heard of, for example, is omega-3s.) They can be beneficial for your health, including improving blood cholesterol levels, easing inflammation, boosting heart health, and more, according to the Harvard TH Chan School of Public Health. Generally speaking, people who follow vegan and Mediterranean diets typically consume more olive oil, nuts, and seeds, and as a result, "they have a higher intake of polyunsaturated and monounsaturated fats," Dr. Arad says.

Saturated fats: Saturated fats are typically found in animal byproducts like beef and chicken, and in coconuts. Depending on who you ask, you'll get mixed opinions on whether saturated fat is good or bad for you. Researchers used to believe that saturated fats caused heart disease, but the papers establishing this link have since been reexamined by nutrition experts, and now, they've largely concluded that saturated fats have no effect on cardiovascular disease, cardiovascular mortality, or total mortality. Larger governing bodies like the WHO and USDA have maintained the recommendation to consume no more than 10 percent of your daily total calories via saturated fat.

Trans fats: Trans fats are "a byproduct of processing food and mainly heating up or applying heat to vegetable oil — this is the worst kind of fat you can put in your body," Dr. Arad explains. Research shows that trans fats negatively affect your vascular system and can increase risk of stroke, heart disease, and heart attacks, he says. The good news is that trans fats have been almost entirely eliminated from the US food supply. In fact, the WHO has called for a worldwide ban on trans fats in the global food supply because of their negative health effects. Previously, trans fats could be found in processed foods such as baked goods made with vegetable oil, potato chips, fried foods, and some dairy-free coffee creamers, according to the Mayo Clinic. They're also found naturally in some animal products like milk, butter, cheese, and meats, according to the FDA.

First, fat is easy for the body to store, which means it's easy for the body to use for energy. "We have been eating fat for as long as we [have] existed . . . so the body is accustomed to processing fat very well," Dr. Arad explains. Your body's first choice for fuel is a quicker energy source called glycogen, but once those reserves run out, it depends on fat to keep you going — whether that's to push through a tough workout or just stay alert through your workday. Plus, fats take longer to digest than carbs, they also help you feel fuller longer after a meal, according to the University of Chicago Medicine.

Some of the important vitamins you get from food (including A, D, E, and K) are fat-soluble, which means that the body absorbs them much better when they're eaten along with fats. Fats from avocados, olive oil, fish, and meat, for example, are "packed with essential nutrients and vitamins that the body needs to maintain health and longevity," Dr. Arad explains.

Last but absolutely not least, fats are necessary for your body to function; they act as messengers and start chemical reactions that help control growth, immune function, reproduction, and other aspects of basic metabolism, according to the National Institute of General Medical Sciences. Omega-3 fatty acids and omega-6 fatty acids, for example, are two essential fats that you need to get from your diet and affect important processes such as cardiovascular function.

Fat is a healthy and important part of your diet, and as long as you're taking care to eat nutritious, whole foods, you probably don't need to worry about how much fat you're eating. Fat can be a quite substantial part of your diet and you can still be very healthy, Dr. Arad says. There's no specific amount of fat you should consume per day, Dr. Arad explains, "because some people can eat 80, 100, 200 grams of fat a day, as long as it's the healthy kind."

If you're still concerned about how much fat you're eating or want more personalized nutrition guidance, speak with a registered dietitian or your doctor, who can give you more specific guidance and help.

Lauren Mazzo was the senior fitness editor at PS. She is a certified personal trainer and fitness nutrition specialist through the American Council on Exercise. Prior to joining PS, she worked for six years as a writer and editor for Shape Magazine covering health, fitness, nutrition, mental health, sex and relationships, beauty, and astrology.

Tamara Pridgett was an associate editor with PS Fitness. She's a NASM-certified personal trainer and Precision Nutrition level 1 coach, and was a Division 1 All-American sprinter.