5 Ways Science Shows That Sugar Causes Weight Gain

March 7, 2021

by Cathe Friedrich

The human tongue loves and craves foods that are high in sugar, but sugar doesn’t always love you back! What’s the problem with sugary foods? Eating a diet high in sugar and refined carbohydrates is linked with weight gain and poor metabolic health. Of course, a high-sugar diet isn’t the only cause of weight gain and obesity, but it’s a strong contributor.

According to Johns Hopkins, several studies show a link between consuming more sugar and obesity. A diet high in sugar may increase the risk of type 2 diabetes and cardiovascular disease. In fact, scientists have identified several ways in which a diet high in sugar causes weight gain. Let’s look at five that are backed by science.

Sugar Increases Insulin Levels Causing Weight Gain

Sugar is a double whammy for your health. When you consume refined carbohydrates or sugary foods, you get a rapid rise in blood sugar because your gut absorbs these foods quickly and this causes insulin to spike and then insulin stays in your bloodstream longer.

Why is this a problem? When your insulin level is high, it’s difficult for your body to burn fat and it’s easier for your body to store it instead. As you store more body fat, your cells become more resistant to insulin and your pancreas has to produce more insulin as your cells aren’t responding as well to the insulin it already makes. More insulin means more weight gain—but it gets worse.

Eventually, your pancreas wears out from producing so much insulin and you become prediabetic or diabetic. When you cross the threshold into diabetes, your risk for other health problems, including cardiovascular disease, kidney damage, blood vessel disease, and retinal damage goes up.

Sugary Foods Won’t Fill You Up

Sugar and refined carbs won’t fill you up as much as whole foods that are high in fiber. When you eat refined foods, you don’t get the same satiety signals as you do with healthier, more nutrient-dense fare. Liquid sources of sugar, like soft drinks, are particularly unfilling, as liquid calories don’t suppress appetite as much as solid food. When you don’t get the necessary signals to stop eating, you eat more than normally would. Over time, this leads to weight gain.

Plus, there’s some evidence that sugary foods activate reward centers in the brain that make you want to keep noshing. There is some truth behind the idea of sugar addiction. Your brain gets a burst of dopamine when you eat ultra-processed carbohydrates and food high in sugar.

What can you do to break the sugar cycle? The best approach is to replace sugar and refined carbs with nutrient-dense, fiber-rich foods like fruits and vegetables and a source of protein, since protein is the most satiating macronutrient.

Sugar Pushes Healthier Fare Out of Your Diet

When you munch on cookies and drink soft drinks, you eat empty calories and that leaves less room for healthier fare. Grabbing packaged foods that are high in sugar becomes an ingrained habit that’s hard to break. The empty calories add up to more body fat, and the more excess fat that accumulates, the harder it is to take off. It’s a vicious cycle.

The good news? If you start gradually cutting back on sugar today by increments, you’ll wean yourself off of sugary foods. Most people have more success when they do it slowly. For example, add one less packet of sugar to your tea or coffee each week and let your taste buds adapt. You’ll reach the point that adding as much sugar as you did before will overwhelm your taste buds.

It’s Easy to Drink Sugar

Another reason sugar leads to weight gain is most of the beverages people drink contain added sugar. Studies show that people don’t consider the calories they drink, but they still count toward weight gains and accumulation of body fat. Those three soft drinks or sugar-sweetened teas you have in a day add up to extra calories without the satisfaction that solid food offers.

Ditching sugar-sweetened beverages is a good first step anyone can take to reduce calorie consumption and the risk of obesity. Plus, it’s often more painless to eliminate sugary beverages than to overhaul the rest of your diet. One step at a time!

Wean Yourself Off of Sugar Slowly

Your taste buds and brain adapt to the diet you feed them. If you feed your body sugary fare, you’ll crave sugary foods. Only by eliminating these foods from your diet slowly and giving your taste buds a chance to adapt will your desire to eat sugar dwindle. The result? You’ll be healthier and have more sustained energy if you wean yourself off of sugar. Do it in increments and it’ll be more manageable.

The Bottom Line

Now that you know how sugar leads to weight gain, what steps will you take to lower the sugar content of your diet? Make a step-by-step plan to replace the sugar and ultra-processed carbohydrates you eat with whole foods and sugar-free beverages, like unsweetened coffee, tea, and water. Then, watch your weight drop and your energy level soar! It’s one of the most powerful steps you can take for your health and well-being.

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