What Does Sugar Do To Your Body

Sugar can sweeten your morning coffee and make that bowl of after dinner ice cream really hit the spot. But what does sugar do to your body and what happens if you eat too much sugar? As with so many things in life, sugar in small doses is usually pretty harmless.

The problem is when you have too much sugar. And if you think you’re someone who feeds that sweet tooth a little too much, you’re not alone. The American Heart Association reports that the average American (adult, teen, and child) consumes about 17 teaspoons of added sugar a day — about two to three times the recommended amount for most people. Over the course of a year, that’s about 60 pounds of sugar.

You can probably imagine that 60 pounds of sugar is too much, and that it’s probably not great for your overall health. Too much sugar circulating in your bloodstream can damage blood vessels, cells, and other tissue.

A 2022 study published in Frontiers in Immunology also suggests that excessive sugar intake can raise levels of inflammation, which can affect brain health and function, increase risks of cancer and other chronic diseases, and interfere with healthy immune function. That means you may have a harder time fighting off infections.

So how bad is sugar, really? Not so bad… in moderation. In fact, sugar is an essential part of a healthy diet. It just depends on how much you consume and what type of sugar is in your diet.

The type of sugar our bodies use for energy is called glucose. The body converts the carbohydrates you eat into glucose — the fuel that keeps you going. Your brain needs glucose to concentrate and your muscles need it to keep you moving. So yes, your body needs sugar.

But glucose doesn’t automatically get stored in your body’s fuel reserves, waiting for you to hit the treadmill or the club for some jogging or dancing, respectively. Glucose needs insulin, a hormone produced by the pancreas, to “unlock” cells in order for glucose to enter and be used for energy later. For people with type 2 diabetes, the body doesn’t produce enough insulin (or any at all) or the body no longer responds to insulin — a condition known as insulin resistance.

When you have a deficit of insulin or you’re experiencing insulin resistance, blood glucose levels rise. And if too much blood glucose circulates for a long period of time, you may develop type 2 diabetes and face many of the complications it brings on, including:

• Diabetic neuropathy (damage to the nerves, usually in the hands and feet)

• Diabetic retinopathy (damage to the tiny blood vessels in the eyes)

• Heart disease

• Kidney disease

• Stroke

While glucose is the body’s main source of energy, most of the glucose the body needs can be obtained from eating whole foods, including fruit, vegetables, whole grains, etc. As a result, you don’t really need the kind of added sugar that shows up in processed foods.  The World Health Organization (WHO) refers to added sugars, as well as sugars naturally present in foods such as honey and fruit juices, as "free sugars.” And in a 2023 report, the WHO recommended reducing the consumption of these free sugars to help prevent a range of health problems, such as tooth decay and obesity (along with obesity-related problems such as type 2 diabetes and heart disease).

A 2023 report in the journal Nutrients suggests that there is little evidence that a high-sugar diet offers any health benefits, but a considerable body of research points to the many health dangers of excessive sugar consumption. Among the health problems cited in the report are type 2 diabetes, high blood pressure, eye problems, peripheral neuropathy (which can cause sores that don’t heal on your feet) and non-alcoholic fatty liver disease.

The researchers also noted that added sugars may be particularly problematic for people with mood disorders and other conditions such as attention-deficit hyperactivity disorder (ADHD). That’s because sugar can interfere with healthy brain chemistry. It can trigger the release of excess dopamine production, which can act like a stimulant and affect mood and attention levels.

Naturally occurring sugars, such as fructose, are what make apples, berries, and other fruits so sweet and tasty. But drinking fruit juice instead of eating the actual fruit doesn’t provide the same health benefits, and the body is impacted differently. In particular, fruits contain fiber, which is important for digestive health and managing your cholesterol and blood sugar levels, among other advantages. Fruit juices don’t contain helpful fiber and often contain added sugars and sweeteners, such as high fructose corn syrup.

Your body digests foods with fiber much more slowly than products such as fruit juices or sodas. The sugar from those sweetened drinks hits your body in a hurry, while the sugar released by your apple or orange enters the bloodstream more slowly. As a result, the sugar from the sodas and fruit juices are converted into calories more quickly and are more likely to contribute to weight gain. Eating foods with fiber also helps you feel fuller sooner and longer.

Turning away from free sugars in the form of soft drinks, sports drinks, sweetened coffee drinks, candy, cakes, and other sweets can require more discipline than many of us possess, especially when you’re with people who are happily getting their sugar fix. Just try to keep in mind that these foods, while sweet and tasty, tend to be low in nutritional value.

Consuming added sugars can have adverse effects on one's overall health. One serious effect is the increase in risk of developing type 2 diabetes, which can then lead to other chronic and debilitating diseases such as kidney disease, circulatory issues, and eye problems. Sugar intake is also implicated in tooth and gum diseases, and in obesity.

The 2015-2020 U.S. Department of Agriculture (USDA) Dietary Guidelines for Americans recommends that individuals make added sugars no more than 10% of their daily calories. If you consume about 2,000 calories a day, that means no more than 200 calories should come from added sugars. That’s about 12 teaspoons of sugar.

The American Heart Association recommends even less sugar in the diet, with no more than 6% of calories coming from added sugars.

If you can cut down on your sugar intake, you might find yourself benefiting from a healthier eating pattern and weight loss. Sugar affects the hormones that control hunger and satiety, which means that sugar consumption can actually trigger the desire to eat more comfort food. That can lead to weight gain, while conversely, less sugar consumption may lead to you eating less and losing weight.

Cutting down on your sugar doesn’t have to be a grueling feat. Taking on the goal often comes down to simple swaps, like drinking sparkling water instead of soda. A few strawberries can be just as satisfying as a bowl of strawberry ice cream, with their natural sugars and fiber to keep you satisfied. And once you get in the habit of relying on healthy snacks like nuts, yogurt, and dried fruit, you may not experience much of those old sugar cravings.

Making healthy diet choices that don’t include large amounts of sugar might mean you’ll have to take a closer look at food labels. You may be surprised how much sugar is in ketchup and other condiments, as well as bread (yes, bread!) and other foods that you might not consider especially sugary.

When you do check out those food labels, remember that sugar comes in many forms, often in words ending in “-ose.” Think of lactose, the naturally occurring sugar in milk and other dairy products. Others include maltose, which comes from the grain malt, and sucrose, the main ingredient in table sugar.

A little sugar can give you a quick boost in energy and alertness. You’ve probably experienced a sugar rush or two in your life. But then comes the sugar crash, along with difficulty concentrating and finding energy to get on with your day.

Those are short-term effects of overdoing it on sugar. Over time, too much sugar can cause some serious health problems related to increased inflammation or damage to your blood vessels and circulatory system.

If you can satisfy your sweet tooth with natural sugars — and even those in moderation — rather than simple sugars like those in table sugar or processed foods, you may be able to avoid serious health problems and chronic diseases, all while savoring some of life’s sweetest rewards.