What Causes a 'Skinny With Belly Fat' Body Shape and What to Do About it

Bodies come in all shapes and sizes, and there's no "ideal" body type or shape. But if you consider yourself to be skinny with extra belly fat, there are some health risks you should know about.

Many people simply look at their body mass index (BMI) or the number on the scale to determine if they're at a healthy body weight. But even if these numbers are in the "healthy" range, having excess fat around your middle puts you in danger for certain health problems.

Keep reading to find out what causes belly fat, why it's so dangerous and how to get rid of it even if you don't really need to lose weight overall.

Medically, people who have a BMI in the healthy range but carry excess belly fat are considered to have normal-weight obesity.

"Those with normal-weight obesity have BMIs that are considered normal but their bodies contain more fat than muscle — higher body fat percentages," says Shanna Levine, MD, owner of NYC's Goals Healthcare.

Contributing factors to this condition include the following, according to Dr. Levine and a January 2022 article in the ​International Journal of Environmental Research and Public Health​:

• Lack of consistent exercise
• Eating an unhealthy diet
• Smoking
• Alcohol consumption
• Genetic factors

Research has also pointed to stress and sleep deprivation as additional causes of belly fat.

In a September 2016 article in ​Nutrition Reviews​, researchers estimated that as many as 30 million Americans may have normal-weight obesity. It can be tricky to diagnose, though, unless you dig deeper than the number on the scale.

"I've seen a person weigh in at 124 pounds with a body fat percentage of 47," says NASM-certified personal trainer Russell Matmon, owner of Pump Fitness in Monroe, New Jersey. "Your weight and body fat don't always match up how you would think."

Researchers are still working to determine what body fat percentage qualifies as "obesity" when overall weight is considered normal, according to the Mayo Clinic.

But when it comes to belly fat, a waist measurement larger than 35 inches for people assigned female at birth or 40 inches for people assigned male at birth is considered unhealthy, according to the National Heart, Lung, and Blood Institute, meaning that it puts you at higher risk for health problems (more on that next).

Not all fat is created equal. Excess fat around your middle is more dangerous than excess fat in other parts of your body, according to Harvard Health Publishing. This visceral fat — the hard fat that lies deep in the abdominal cavity and wraps around your organs — is metabolically active, producing chemicals that are associated with a host of diseases.

These chemicals include proteins called cytokines, along with other hormones, which can cause low-level inflammation and lead to illness.

According to Harvard Health Publishing and a September 2019 article in ​Nature Medicine​, this type of fat is connected to an increased risk for:

• Hypertension
• Heart attack
• Type 2 diabetes
• Metabolic syndrome

Research has also linked too much belly fat to asthma, dementia and cancer.

People who have normal-weight obesity are known colloquially as "skinny fat." In the ​Nutrition Reviews​ article mentioned above, those individuals have a very high cardiometabolic risk (aka the risk for developing diabetes or heart problems) — similar to those with severe obesity.

And a January 2014 article in ​Progress in Cardiovascular Disease​ confirmed that people with coronary artery disease who are of normal weight but have excess belly fat actually have the highest mortality risk when compared to people with other patterns of fat distribution.

Normal-weight obesity also has a very high chance of leading to metabolic obesity in people with normal body weight, according to the ​Nutrition Reviews​ article. This is when an individual of appropriate weight (per BMI) has actual changes related to metabolic syndrome, such as excess visceral fat, hyperinsulinemia or insulin resistance, high cholesterol, high blood pressure and an increased risk for type 2 diabetes.

Although genetics play a role in your body shape, there are certain lifestyle changes that can help you get rid of excess belly fat and lower your chances of a related health issue.

Someone with normal-weight obesity likely isn't overeating, but the quality of the calories they're consuming is probably poor. Eating too many processed foods and refined carbs — including white bread and pasta, chips, sweets and fast foods — will cause sharp spikes in blood sugar and raise triglyceride levels, which will lead to a bigger belly bulge, according to Harvard Health Publishing.

Instead: "Pack your diet with healthy, fiber-rich foods like fruits and vegetables, healthy fats and lean protein," says Dr. Levine. "Daily fiber goals of 25 to 30 grams a day will decrease daily blood sugar and aid in fat loss."

If this is more fiber than you normally eat, drinking more water is also essential, she says, to keep your digestion on track.

If you're the type who likes to follow a specific diet plan, consider the Mediterranean diet. This way of eating puts the focus on whole grains (think: brown rice, oatmeal, bulgur) rather than refined carbs and spotlights fruits, vegetables and healthy fats like olive oil and avocado.

An August 2019 paper in the ​Journal of Hepatalogy​ found that a lower-carb Mediterranean diet was more effective at reducing belly fat than a diet lower in fat.

Regular exercise is important for everyone, even if weight loss isn't your goal. Stomach fat is very responsive to exercise, per Harvard Health Publishing.

According to the Department of Health and Human Services' ​Physical Activity Guidelines for Americans​, adults should aim for at least 150 minutes of moderate-intensity physical activity each week along with at least two strength-training sessions.

Indeed, an April 2014 study in the ​Journal of Sports Sciences​ found that cardio combined with resistance training had greater results concerning decreased body fat mass and increased lean muscle than with just cardio alone.

So, including regular weight training each week in your routine is a must. The CDC recommends getting started with at least one set of 8 to 12 repetitions of an exercise that addresses every major group performed twice weekly. As the weeks progress and you feel stronger, move to heavier weights and/or more sets.

Weight training helps you build muscle, which in turn helps your body burn more fat and look more toned, according to the American Council on Exercise. But take note that "There's no such thing as spot reduction," says Matmon. "Just because you do abdominal exercises doesn't necessarily mean you'll lose fat in your stomach. But you can definitely tighten and tone that area with some awesome core workouts."

Matmon believes that the core and lower back should be the strongest part of your body. Along with working the rest of your muscles, his favorite core exercises to help shed belly fat and tone up are:

• Planks
• Dead bugs
• Leg swings
• Hollow body holds
  

Rotate through these four exercises three times for 1 minute each, with a 30-second break in between each one. Do them once a day.

High-intensity interval training (HIIT) workouts involve repeated bursts of high-intensity activity followed by lower-intensity recovery times, according to the American College of Sports Medicine, such as alternating sprinting for 30 seconds with walking for 15 seconds.

A June 2017 article in ​Obesity Reviews​ found that short-term HIIT workouts can lead to a reasonable amount of body composition improvements without even losing weight, despite minimal time commitment.

And just a quick note that HIIT is a more advanced workout method, so if you're brand new to cardio, spend a few weeks improving your fitness before introducing high-intensity intervals.

"You can do any of these workouts in the privacy of your own home, but I always recommend you have a trainer with you to make sure you do them correctly, especially if you're just starting out," says Matmon.

Lack of shut-eye (that is, getting less than seven hours a night) could contribute to a larger waistline. Indeed, an April 2022 randomized controlled trial in the ​Journal of the American College of Cardiology​ found that sleep restriction leads people to eat more and increases the risk for abdominal obesity.

This was a small study, of only 12 people, but it builds on previous research in this area that links a shortage of zzzs with more belly fat.

Make slumber a priority by following these healthy sleep habits:

• Turn off screens (think: TV, phones) at least an hour before bed and do something relaxing before you hit the hay, like showering or reading a book
• Make sure your bedroom is cool, dark and quiet
• Avoid caffeine and alcohol for a few hours before bedtime
• Get at least 15 minutes of direct sunlight in the morning
• Exercise regularly (but not too close to bedtime)
• Go to bed and wake up at the same time every day

Being stressed can increase belly fat because it triggers the hormone cortisol, which tells your body to store fat in your abdominal area.

Different habits help relieve stress for different people, so try a few of these go-tos to see what works best for you:

• Yoga
• Meditation
• Exercise
• Coloring
• Spending time with loved ones
• Breathing exercises
• Spending time outside