If You Can't Seem to Lose Belly Fat, Experts Ask, "Are You Eating Too Much Sugar?"

When we eat, the pancreas produces insulin. Eating sugar (or any carbohydrate) will cause insulin levels to increase, explained weight-loss physician Linda Hodges, DO. Insulin's job is to take the sugar from food and bring it into the brain and muscle cells that use it as fuel, explained Vera Tarman, MD, an addiction physician who works with people who struggle with food and sugar addiction.

Insulin helps keep your blood sugar in a certain range, and when you eat sugar, it requires more insulin to complete that task. "If one is constantly over-consuming sugar, insulin levels can eventually remain high all the time," Dr. Hodges explained.

Why are high levels of insulin bad for weight loss? Jason Fung, MD, a nephrologist (kidney specialist) who specializes in obesity told POPSUGAR that the issue with weight gain isn't too many calories, it's "too much insulin." Eating sugar causes insulin levels to rise, which signals your body to store fat.

"Refined sugar overwhelms our natural hormonal treatment of sugar and the body (through insulin spikes) takes the excess sugar and parks it into the abdomen," Dr. Tarman explained. That's why insulin is known as the 'fat-storing hormone," she said.

Fat stored inside the abdomen beneath your abdominal muscles around your organs is known as visceral fat. This type of fat can not only lead to inflammation, Hodges said, but Dr. Tarman added that visceral fat "is the visual warning of illnesses such as diabetes and heart disease to come." Eating too much sugar and gaining visceral fat can create what doctors call metabolic syndrome, which could not only lead to the diseases previously mentioned, but also high cholesterol, Alzheimer's, and cancer, Dr. Tarman explained.

Aside from raising insulin levels, another thing to be mindful of is that sugary foods and beverages, and refined carbs tend to be calorie-dense, yet very low in nutrients, explained Melissa Morris of Exercise.com, an ACSM-certified exercise physiologist and nutrition and applied kinesiology professor at the University of Tampa. As an ISSN-certified sports nutritionist, Morris explained that since sugary foods don't offer the protein, fiber, and healthy fats to make us feel satiated, it's easy to over-consume them, increasing our daily calorie intake, which can lead to weight gain and belly fat.

High levels of insulin in the blood also block leptin signals (the "I'm full" hormone) to the brain, explained Susan Peirce Thompson, a psychology professor with a PhD in brain and cognitive science, in a previous interview. Your brain doesn't see that you're full, so when you eat sweet treats, it thinks you're starving and increases cravings and hunger, making you eat more.

Since eating sugary foods and refined carbs raises insulin levels, and high levels of insulin signal the body to store fat, Dr. Fung said that keeping your insulin levels low by limiting these types of foods and focusing on lean protein and healthy fats is a simple way to help lower your overall body fat percentage, reducing belly fat.

Registered dietitian Claire Virga, MS, reminded us that there's a big difference between added sugars like white sugar and maple syrup, and natural sugars, such as those found in fruit, vegetables, and complex carbohydrates. "Natural sugars are packaged with fiber and other important micronutrients. Fiber helps to blunt our blood sugar response to these foods, which promotes a stable rise in blood sugar," Virga explained. "Unrefined sugars from complex carbs like vegetables get broken down over time and there is little excess sugar to be stored as it gets used for fuel," added Dr. Tarman.

In contrast, added sugars are typically found in foods and beverages with little to no fiber like candy, baked goods, and soda. "These are the foods which promote the rapid increase in blood sugar and insulin and subsequent fat storage," Virga explained. "When you eat refined carbs (think highly-concentrated large amounts of sugar — more than your brain needs or can use) the insulin has to spike to mop up the extra sugar. More gets sent to the fat cells; the belly fat cells," Dr. Tarman said.

Registered dietitian and NYC-based certified diabetes educator Rachel Stahl, MS, CDN, pointed out that refined sugars can come from many sources. "Whether it's granulated white sugar, high-fructose corn syrup, or something that sounds fancier, such as beet juice concentrate or raw sugar, these are all added sugars," Stahl explained.

OK, so hold up. While fresh fruit is delicious, you cannot live on bananas and apples alone! Sometimes eating pie or chocolate (or both!) is a non-negotiable. Eating sugar can bring us joy and is often a part of celebrations and social gatherings. That's good for our mental health, which is equally as important as our physical health. Plus, giving up sugar entirely can feel too rigid, and could lead to binge-eating later. So, can you still eat sugar and lose belly fat?

According to the American Heart Association, women should limit added sugar intake to six teaspoons per day (approximately 100 calories). "That means on a 2,000-calorie day, sugar consumption should be 25 grams," suggested registered dietitian Anika Christ, RD, with Life Time.

Virga and Christ agree that most people know sugar is found in foods like candy and cookies but added sugars are hidden in so many processed foods. "Check food labels closely and you'll find added sugar in things like sauces, dressings, cereals, yogurt, juices, nut butters, and dried fruit," said Virga. So be on the lookout and try to limit your daily added sugar intake to 25 grams.

Dr. Tarman said to focus on whole foods that are naturally sweet like fruit and veggies to satisfy your cravings, because the less refined sugar and simple carbs you eat, the more weight you will lose.