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Exercise can boost your body's fat-burning abilities, but it's less important than what you eat.
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Having a lot of body fat doesn't just make it harder to fit into your jeans. Too-high levels are tied to serious health risks like high blood pressure, diabetes, heart disease and even some types of cancer, per the American Heart Association. But what's the best way to bring your body fat levels down into the healthy range?


Trying to lose body fat can sometimes feel complicated. But there are a variety of solutions that can help with getting leaner. Here's a look at why some of us end up with excess fat along with the best ways to lose body fat for good.

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The Skinny on Body Fat

Before diving into the best ways to lose fat, it helps to understand a little bit about how we gain fat in the first place — and what our bodies do with it. We need some body fat for our bodies to function properly, but too much can cause health problems. Basically, fat storage happens when we consume more calories than our bodies need.

When we eat, our bodies release the hormone insulin. Insulin helps the body's cells absorb glucose — or blood sugar — and fatty acids from food to be used as energy, explains board-certified obesity medicine physician Jaime Harper, MD. Any extra calories that ‌don't‌ need to be used as energy get saved in our fat cells for later.

Fat storage is an evolutionary mechanism that helped our ancestors survive in times of famine: When there wasn't much food around, the body could stay fueled by burning through its fat stores. We still burn fat the same way today whenever we use up more energy than we take in.


"When we haven't eaten in a few hours or begin to exercise, the body's hormonal state signals to fat cells to release some fat for energy," says Georgie Fear, RD, CSSD, author of ‌Lean Habits for Lifelong Weight Loss‌.

Enzymes break down stored fat into fatty acids and other components, which are then released from the cell and taken up by other cells to burn for energy. Burning the fatty acids produces water and carbon dioxide, which exit the body through our urine, sweat and breath. Over time, that adds up to body fat — and pounds — lost.


Losing Weight vs. Losing Fat

When most people say that they want to lose weight, what they really mean is that they want to lose ‌fat‌. The body's total weight is made up of water, muscle, bones and fat, Dr. Harper explains. Fat is the squishy stuff that sits beneath the surface of the skin and around your body's organs and makes your jeans feel tight. It's also what ups the risk for serious health problems, especially when the fat accumulates around your internal organs (what's known as "hard fat").



The thing is, there are ways to lose weight that don't involve losing much actual fat. Sweating a lot, for instance, can cause you to lose several pounds of water weight.

"But it's just fluid weight. In that case, fat and weight loss aren't the same thing," says Anis Rehman, MD, associate program director of the Endocrine Fellowship at Southern Illinois University School of Medicine.


As soon as you consume the lost fluids, your weight will bounce right back up to its usual number. But in order to actually get leaner and improve your health, you need to lose body fat.

What Is the Science Behind Fat Loss?

When a person takes in more calories than their body needs for energy, the extra energy is stored in fat or adipocyte cells for later use. That energy, or fat, can be broken down and used when a person burns more calories than they are storing, explains David Nazarian, MD, director of Weight Loss Clinic Los Angeles.


Experts call this process lipolysis, where fat from the body's adipocyte cells is broken down and used for energy. When your body senses that you're using more energy than you're taking in, fat-targeting hormones and enzymes including epinephrine, norepinephrine, cortisol, glucagon and growth hormones begin metabolizing the fat so it can be used as an energy source, Dr. Nazarian says. Over time, this can lead to weight loss.

How Does Fat Leave the Body?

Fat loss happens when you consistently take in fewer calories than you need for energy, forcing the body to turn to its fat reserves to keep you fueled. After the fat is broken down, the body is left with metabolic byproducts, or waste, that need to leave the body. These byproducts make their exit via sweat or urine, or through carbon dioxide when you breathe out, according to the Cleveland Clinic.



Which Part of the Body Loses Fat First?

Despite claims that say otherwise, you can't target excess fat in certain parts of the body (like your belly or butt). Instead, fat loss tends to happen little by little, all over the body.

"Fat cells are distributed throughout our bodies and are typically lost throughout the body at the same time rather than in specific places," Dr. Nazarian explains.

How Much Body Fat Is Healthy?

No two bodies are exactly alike, and everything from your age to your hormones and genetics all play a role in how much body fat you have — and how easy or difficult it is to get leaner. Men also tend to have less body fat than women, and athletes generally have less body fat than non-athletes.

Here's a look at what's considered a healthy body fat percentage, according to the American Council on Exercise (ACE):

Body Fat Norms for Women

  • Acceptable:‌ 25-31%
  • Fitness:‌ 21-24%
  • Athletes:‌ 14-20%
  • Essential:‌ 10-13%

Body Fat Norms for Men

  • Acceptable:‌ 18-24%
  • Fitness:‌ 14-17%
  • Athletes:‌ 6-13%
  • Essential:‌ 2-5%

Losing Fat Through Diet

Our body fat has many functions, one of which is to serve as a backup source of energy for when food is scarce. So it makes sense that cutting your overall calorie intake is one of the most effective ways to burn fat.

How much should you cut your calories, exactly? Most experts recommend trying to eat 250 to 500 fewer calories per day. "That will enable you to lose 1/2 to 1 pound a week," says Fear. However, you may not lose weight at this exact rate because of other factors at play (which we'll get to a bit later).


Also, it might be tempting to slash your intake by more than that, especially if you're trying to jumpstart your weight loss or want to see results fast. But the move could actually backfire: "It can induce compensatory changes in your body, such as burning fewer calories when you exercise, along with lower levels of thyroid and sex hormones," Fear says.

Not to mention that extremely low-cal diets are hard to sustain, because they tend to leave most people feeling hungry and deprived.

It's worth noting that not all experts support this "calories in, calories out" theory. Instead, some subscribe to the carbohydrate-insulin model of obesity, which says eating highly processed carbohydrates (think: packaged snack foods, white bread, pastries and other desserts) causes hormonal changes in the body that encourage it to store more fat and increase appetite, which leads to overeating, according to a July 2022 paper in the European Journal of Clinical Nutrition.

Another theory is that overweight and obesity are caused by inflammation in the body, which results from eating inflammatory foods such as fatty cuts of red meat, refined sugary foods and excess alcohol, according to the Harvard T.H. Chan School of Public Health.

What's the Best Fat-Burning Diet?

Calories aside, what about the foods themselves — can certain types of diets help you lose more body fat than others? The keto diet, for instance, is often touted as the best way to lose weight, because cutting your carbs super low encourages the body to switch to burning fat for fuel.

Low-Carb Diets

Indeed, research has shown that low-carb diets are more effective for weight loss than low-fat diets — at least for the first six to 12 months, per a July 2019 review in ‌StatPearls‌. "They can reduce how hungry you feel, which some people find as a helpful tool that enables them to eat less," Fear says.


But the fat-loss benefits are less clear beyond the one-year mark, according to the Mayo Clinic. And there could be other risks: A six-year study of 25,000 people published April 2019 in the ‌European Heart Journal‌ found that people who ate the lowest-carb diets had a 32 percent higher chance of dying from any cause compared to those who ate the most carbs.

In short? Low-carb diets might be helpful for losing fat at first, but they may not be a healthy, sustainable way of eating in the long term for most people.

Carbohydrate-Insulin Model

For those who subscribe to the carbohydrate-insulin model of obesity, dietary changes for weight loss are more about quality than quantity. According to an August 2018 paper in JAMA Internal Medicine, people should do the following to lose fat:

  • Eat fewer refined grains (i.e. white bread, pasta and rice; packaged snacks; desserts), potato products and added sugars
  • Prioritize non-refined carbs such as nonstarchy veggies, veggies and non-tropical whole fruits (apples, pears, berries, peaches, etc.)
  • Choose whole-grain foods such as whole barley, quinoa and traditionally fermented sourdough made from stone ground flour)
  • Opt for foods with healthy fats, such as nuts, seeds, avocado and olive oil
  • Eat an adequate amount of protein, including plant-based sources (think: tofu, beans, nuts and seeds)

The authors also note it's important to reduce your exposure to chemicals that can interfere with the body's hormones by drinking filtered water, using glass instead of plastic food containers and avoiding "obesogenic" food additives such as certain preservatives and artificial sweeteners and colors.

High-Fiber Diet

Another approach says the best fat-burning diet is simply high in fiber. Fiber is a nutrient found in plant-based whole foods including fruits, vegetables, beans, nuts, seeds and whole grains like oatmeal and brown rice. A February 2015 randomized trial in the Annals of Internal Medicine that followed 240 people for a year found that just aiming to eat 30 grams of fiber each day was enough to help them burn fat.

Fiber-rich foods tend to be more filling but also lower in calories than low-fiber foods, and they also tend to be less processed.

Anti-Inflammatory Diet

If you want to burn fat by reducing inflammation, on the other hand, an anti-inflammatory diet encourages eating fruits, vegetables, high-fiber whole grains, legumes (beans, peas) and healthy fats such as avocados, olive oil, nuts, seeds and fatty fish like salmon and mackerel. Beverage-wise, this diet includes tea and coffee while limiting alcohol, according to the Harvard T.H. Chan School of Public Health.

Intermittent Fasting

When‌ you eat may also play a role. "I recommend intermittent fasting to my patients, having them eat for eight hours and fast for 16 hours," Dr. Harper says. (This is one approach to intermittent fasting, but there are others, such as eating during a 12-hour window and fasting during the other 12 hours, or eating normally five days per week and restricting calories the other two days.)

Indeed, intermittent fasting has been shown to help with weight loss better than simply restricting calories throughout the day, according to a 50-week study of women with overweight and obesity published November 2018 in ‌The American Journal of Clinical Nutrition‌.

"In a fasting state, the body doesn't release the hormone insulin. Without insulin, the body doesn't store fat and instead breaks down fat you already have for energy," Dr. Harper explains.

Is Intermittent Fasting Only Effective While on a Caloric Deficit?

Successful weight loss happens when your body uses more calories than you take in. Intermittent fasting can help you curb your calorie intake and encourage your body to burn more fat, but traditional healthy eating patterns can too.

Losing Fat Through Exercise

Paying attention to what and how much you eat is the most important factor when it comes to fat loss. But you can torch additional calories — and get more fat-burning bang for your buck — by adding in regular exercise. "Literature shows that a combo approach of diet and exercise is best," Dr. Rehman says.

Indeed, research shows that physical activity alone isn't usually enough to encourage fat loss: A landmark review of 80 studies in October 2007's ‌Journal of the American Dietetic Association‌ found that exercising alone — without diet changes — leads to minimal weight loss at best. And research done since then has backed up this position.

But exercise ‌is‌ a great way to support eating for fat loss — and it could help you reach your goal a little faster. "If we eat 1,800 calories a day and use 1,800 calories a day, then burn an additional 200 calories from exercise, the body will turn to stored fat for energy since there's no leftover glycogen stores from what we've eaten," says Richard Wilcock, certified strength and conditioning specialist and owner of Flagship Fitness.

Should You Do Cardio or Weights While on a Calorie Deficit?

Both cardio and weight-training should have a place in your weekly workout routine when you're cutting calories to lose fat.

Cardio burns more calories than strength-training, thus leading to quicker fat loss. Weight-training doesn't burn as many calories (30 minutes of strength training burns around 100 calories), but it'll help you preserve or even gain lean muscle mass. That's important, because the more muscle tissue you have, the higher your calorie burn will be (even when you're at rest!), according to the Mayo Clinic. And the more calories you're burning, the fewer excess calories will potentially end up being stored as fat.

What Exercises Reduce Body Fat?

So, what are the best fat-burning exercises? If you're looking to burn the most calories in the shortest amount of time, high-intensity interval training (HIIT) — like alternating jogging with sprinting — might be the way to go.

"Fat loss is all about using more energy than you consume, so whichever exercise burns the most energy would be the best for fat loss," says Wilcock. "HIIT is very efficient. You can burn a lot of energy in a short amount of time — say, around 500 calories in a 45-minute session."

What's more, interval workouts could keep your body in a calorie-torching state even after you're done exercising. One February 2012 study in the ‌International Journal of Sport Nutrition and Exercise Metabolism‌ found that subjects who completed sprint intervals continued burning fat for up to an hour after the sprints were over.

Keep in mind, these exercises will help you burn fat all over your body. Despite the fact that you might want to get leaner in one specific area, that's not how fat loss works, say Dr. Rehman. Endless crunches won't burn away belly fat, and tons of squats won't burn fat around your thighs.

When to Exercise for Fat Loss

Another tip: If you can, consider working out first thing in the morning before eating breakfast. Because your body's glycogen levels are bottomed out from not eating since the night before, it'll turn to your stored fat for energy pretty quickly, which can boost your fat-burning overall.

In fact, one October 2019 study in the Journal of Clinical Endocrinology and Metabolism found that subjects who exercised before breakfast burned double the amount of fat compared to those who worked out later in the day, after eating.

Sleep for Fat Loss

Sleeping doesn't burn tons of calories. But getting enough rest still plays an important role in reaching and maintaining your weight-loss goals, experts say, because it can affect your ability to stick with healthy habits.

"Sleep loss or poor sleep quality seems to lead to weight gain or difficulty losing weight," says Michael Grandner, PhD, director of the Sleep and Health Research Program at the University of Arizona and lead scientific advisor at Sleep Reset.

Why Is Sleep So Important for Losing Weight?

"Sleep and weight are more closely related than people think," says Dr. Grandner. That's in part because sleep is involved in helping the body regulate basic processes related to metabolism, immune function, stress management and cardiovascular function. When you fall short on shut-eye, "all of these elements can get disrupted, and all of them play roles in weight management," Dr. Grandner explains.

Sleep deprivation can directly affect your behavior as well. Disturbed sleeping patterns drive us to take in more calories, mainly through snacks rich in refined carbohydrates and fat, per an April 2022 review in ‌Nutrients‌. "Lack of sleep predisposes people to be up later at night, which tends to lead to over-consumption of unhealthy foods at a time when your body doesn't really need the extra calories," says Dr. Grandner.

On the flip side, simply getting an adequate amount of sleep can help you eat less and make it easier to reach your weight-loss goals. One February 2022 ‌JAMA‌ study found that adults with overweight consumed 270 fewer calories per day when they went from sleeping 6.5 hours per night to 8.5 hours. That alone could translate to a weight loss of roughly 28 pounds in a year.

How Do You Burn Fat While Sleeping?

You don't exactly lose weight during sleep. Sleep isn't a major fat burner because your body doesn't use as much energy while you're snoozing. But it still requires calories to carry out basic functions like breathing or maintaining your body temperature, which are happening around the clock.

"Our bodies are constantly in need of energy, and our bodies do burn fat while we sleep. But the rate is slower, since our metabolism and energy needs are lower when sleeping," Dr. Nazarian says.

It's important to note, though, that the hormones that influence appetite (such as ghrelin and leptin) are reset during proper sleep. So getting enough sleep helps indirectly with fat burning by helping to regulate your appetite.

Gut Health for Fat Loss

It's no secret that the health of your microbiome — the community of bacteria living in your gut — play a major role in your health overall, including your weight. "There is more and more evidence showing that overweight individuals have different composition of gut bacteria than lean individuals," says Felix Spiegel, MD, a bariatric surgeon at Memorial Hermann in Houston, Texas.

Here's why: Certain types of bacteria have been shown to be more efficient at breaking down food particles in the gut and help absorb more calories, increasing the chance for obesity. People with obesity have a higher proportion of these more efficient gut bacteria, Dr. Spiegel explains, while people who do not have overweight have higher concentrations of less efficient gut bacteria, and in turn, absorb fewer food particles in their gut.

The types of bacteria in your gut aren't fixed, though. Healthy eating patterns, like a Mediterranean-style diet, can promote higher numbers of bacteria that may support weight loss, per a January 2021 study in ‌Nutrients‌. So, too, can engaging in regular moderate exercise, according to another ‌Nutrients‌ study from November 2021. Even the act of losing weight itself seems to increase the number of beneficial bacteria in the gut, a January 2022 ‌Gut Microbes‌ review concluded.

Experts still have a lot to learn about the relationship between gut health and weight, and it's hard to say for certain which strains of bacteria could be the most helpful for weight loss, Dr. Spiegel points out. But engaging in gut-friendly habits as a whole seem to be helpful, so consider the following when you're working toward losing fat:

  • Eat a diverse, plant-based diet
  • Include foods high in probiotics like yogurt
  • Avoid artificial sweeteners
  • Practice good oral hygiene
  • Get the recommended seven to nine hours of sleep each night
  • Exercise regularly
  • Limit alcohol
  • Manage your stress

Fat Loss for Men vs. Women

Women and men lose body fat in the same way, but sex can affect how quickly (or slowly) a person is able to lose fat. Men have higher levels of the hormone testosterone, which promotes the growth of lean muscle tissue and can make fat loss quicker and easier. One August 2018 study in ‌Diabetes, Obesity, and Metabolism‌ found that when subjects ate the same low-calorie diet for eight weeks, male subjects lost an average of 26 pounds while female subjects lost an average of 22.

Sex also determines ‌where‌ your body is most likely to store much of its fat. "For men, the main area is the stomach. For women, it's the breasts, bum and thighs," says Wilcock.

That's not to say that women can't lose body fat or reach their desired body fat percentage. But they might have to work a little bit harder.

The Cleveland Clinic recommends women do 30 minutes of resistance training at least twice a week to boost muscle mass. And of course, pay close attention to how many calories you're taking in. While everyone's calorie needs are a little different, women may need to eat between 1,200 and 1,800 calories daily to lose weight. But keep in mind that the right number depends on a wide variety of factors, including your age, current weight and activity level.

Measuring Fat Loss

When you're trying to lose fat, it helps to know where exactly you're starting from. While a typical bathroom scale can tell you how much you weigh, it's not the best tool for figuring out your body fat percentage or tracking your fat loss.

For that, you'll need body fat calipers. This handheld device is designed to measure the thickness of skin at the biceps, triceps, low shoulder blade and hip, which experts can use to calculate your body's percentage of fat. Since it's tough to take accurate skinfold measurements at home, your best bet is to have it done by a personal trainer or health practitioner.

Calipers aren't the only tool for measuring body fat, but they're widely considered to be the simplest and least expensive, per the ACE. The problem is, while calipers are fairly accurate, they're not foolproof.

If you're looking for a super precise measurement, consider getting a dual X-ray absorptiometry (DEXA) scan. These scans send small electrical currents through the body to give a super accurate analysis of a person's weight, body fat, muscle mass and water. "It's considered the gold standard in measuring body composition, but it is expensive, not convenient and it does give off a small dose of radiation," Dr. Harper says.

A body composition scale — either at home or in a doctor's office — is a useful alternative and can be fairly accurate depending on the quality of the scale.


You can use's Body Fat Calculator to help determine how much body fat you have/want to lose.

Bottom Line: The Best Way to Burn Fat

Our bodies store fat when we take in more energy than we use up. So in order to lose fat, we need to reverse that process.

By using more calories than you take in, your body will burn fat from its fat stores to cover the rest of your energy needs. Eating a lower-calorie diet is one way to make that happen, but you might also consider changing when you eat (intermittent fasting) and the quality of the foods you're taking in (fewer processed fare and more nutritious, high-fiber and anti-inflammatory foods).

You can get an extra boost by exercising regularly, especially with interval or strength-training workouts. And you can help support the process by getting adequate sleep and nurturing your gut health.

FAQs About Losing Body Fat

Have more questions about reaching your weight loss goals? We've got answers.

Why Is It So Hard to Lose Weight?

Our bodies are good at maintaining and gaining weight because, historically, that's helped us survive tough times. Remember, our bodies store fat in preparation for possible times of food scarcity. This makes it hard to lose weight.

Plus, some factors (like your genetics, for example) are out of your control. But adopting healthy, sustainable habits — like eating right and being active — can help, as can using metabolic tools like medications if needed.

Big changes aren't easy, of course, and when you try to make too many drastic shifts at once, they can feel overwhelming and become hard to stick with, says Dr. Nazarian. And when that happens, any weight you might've managed to lose will creep back.

The key, instead, is making shifts that you can really live with. That might mean enjoying a moderate portion of dessert when a craving strikes instead of trying to swear off sugar for good, or committing to walking for 30 minutes most days of the week instead of trying to run for an hour every single day. When your healthy habits feel sustainable, you'll be more likely to stick with them and eventually lose weight.

How Do You Lose Body Fat Quickly?

Fat loss happens when you burn more energy than your body takes in. You can speed the process along by drastically cutting your calorie intake or engaging in extreme exercise. This crash-diet approach tends to be hard to keep up, though, and it can result in the loss of lean muscle mass. As a result, "these types of diets aren't usually successful and one gains the weight back," Dr. Nazarian says.

A slow-and-steady approach tends to be more successful. "Healthy weight loss is 1 to 2 pounds per week," says Dr. Nazarian. That can typically be achieved by reducing your calorie intake by around 500 calories per day and making other lifestyle changes, the Mayo Clinic notes.

What Burns the Most Body Fat?

The best way to burn body fat — especially if you want to lose body fat without losing weight — is through a combination of dietary changes and increasing your activity level. There's no one-size-fits-all way to do that. Cardiovascular exercises like walking, running, cycling or swimming can all be effective, but so can high-intensity workouts or intervals if you're pressed for time, Dr. Nazarian notes.

But if you really want to change your body composition for the better, add resistance exercises to your routine to work toward building more lean muscle mass. When combined with diet changes, resistance exercises have been shown to boost metabolism and help you burn more calories, per a January 2018 review in the ‌International Journal of Sport Nutrition and Exercise Metabolism‌.

"Muscle burns fat at a higher rate, and increasing your body's lean muscle mass will cause an increase in metabolism and higher calorie expenditure," says Dr. Nazarian.

At What BMI Do You Start to Lose Muscle Instead of Fat?

Body mass index or BMI is a number that uses height and weight to calculate how much body fat a person has. It may be helpful for your doctor to determine whether you have underweight, overweight or obesity (though experts agree it's not perfect). But: "There is no specific BMI at which muscle loss begins to occur," Dr. Nazarian says.

Why Is It So Hard to Drop 50 Pounds?

It's possible to lose large amounts of weight — and to lose body fat when you have a high body fat percentage — but it takes dedication, patience and time. Because experts recommend aiming to drop just 1 to 2 pounds per week, losing 50 pounds could take several months to a year or more. That might be longer than you'd like, but it's normal — and in fact, it improves the odds that you'll be able to maintain your loss for the long run.

What Are the Causes and Effects of Failing to Lose Weight?

Excess body fat can lead to a number of negative health effects over time. According to the Centers for Disease Control and Prevention (CDC), these may include:

  • High blood pressure
  • High cholesterol
  • Type 2 diabetes
  • Heart disease
  • Stroke
  • Gallbladder disease
  • Osteoarthritis
  • Sleep apnea
  • Some forms of cancer
  • Depression and anxiety
  • Body pain

The good news is, your risk for many of these conditions drops significantly when you lose weight. So consider what sustainable healthy changes you can work on and get started.




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