How Sugar Causes Inflammation—and What You Can Do About It

Most people know that fresh, unprocessed foods—like berries, olive oil, salmon, and leafy greens—help our body stave off chronic inflammation (aka what happens when our body's "fending off" response persists and leaves us in a constant state of alert). It's no secret that chronic inflammation can be detrimental to our health: It's been linked to many diseases, including cancer, heart disease, diabetes, depression, arthritis, and Alzheimer's.

But does sugar cause inflammation? Here, we speak with a registered dietitian to discuss the effects of added sugar on the body. While many foods contain sugar, it's added sugars that can lead to chronic inflammation. In this article, we refer to added sugars as sugar.

How Much Sugar Causes Inflammation?

Studies have shown that a high daily intake of sugar (beyond what's recommended) can have inflammatory effects on the body. But how much sugar is too much sugar? "According to the Dietary Guidelines for Americans, we should keep our intake of added sugars to less than 10 percent of our total daily calories as part of a healthy diet," says Samantha Bartholomew, MS, RDN.

Ten percent of your total calories equals 200 calories of added sugars a day in a typical 2,000-calorie diet—or about 12 teaspoons of added sugar. For reference, a standard 12-ounce can of soda has about 126 calories of sugar.

The American Heart Association is more conservative, recommending between 100 to 150 calories per day (about six to nine teaspoons or 32 to 36 grams of added sugar).

How Sugar Causes Inflammation

Several foods can heighten inflammation, and sugar is one ingredient near the top of that list. Here are the top ways sugar causes inflammation in the body.

Creates AGEs

When protein or fat combines with sugar in our blood, it produces compounds called Advanced Glycation End Products (AGEs) via a process called glycation. AGEs also form when cooking food at high temperatures (like frying or grilling) through the Maillard reaction.

While your body works to eliminate AGEs, if too many develop or are consumed, the body can't keep up with the rapid accumulation. High levels of AGEs can harm cells in the body and lead to health issues, including inflammation.

Additionally, when combined with a high-fat diet, sugar leads to excess CML production. CML [N(ε)-(Carboxymethyl)-Lysine] is a significant AGE that can stimulate inflammation in the brain, which may lead to neurological disorders.

Allows Bacteria to Enter the Blood

Too much sugar can affect our gut health and cause our guts to become more permeable. This allows bacteria and other inflammatory particles to more easily enter our blood. Our immune system—in an effort to fight off the bacteria—then attacks the body's tissues, which leads to inflammation.

Increases Cholesterol

Sugar and other inflammatory foods cause our "bad" (LDL) cholesterol to rise, and because the body wants to heal, it triggers an inflammatory response to combat the increased cholesterol levels. The increased inflammation leads to more C-reactive protein (CRP), a common indicator that the body is experiencing inflammation or infection.

However, some studies show that CRP also helps regulate inflammation in addition to indicating its presence. This creates a cycle of sorts: Too much sugar increases LDL cholesterol, which causes inflammation, which increases CRP levels, which affects the body's ability to control inflammation.

Leads to Insulin Resistance

It's well known that eating too many added sugars can cause weight gain, which leads to excess body fat. In turn, this can result in insulin resistance, which prevents your body from adequately processing glucose.

Insulin resistance also triggers the body to increase production of the MCP1 protein, which then activates inflammatory cells. This reaction to insulin resistance and the increase in pro-inflammatory cells can lead to low-grade inflammation in the body.

Tips for Reducing Sugar Intake

According to Bartholomew, the key to avoiding inflammation is to educate yourself on your daily sugar intake (particularly when it comes to foods that don't need it), curtail it, and find suitable sugar replacements. Follow these tips for reducing your sugar intake.

• Read labels. "Start by reading ingredient labels," Bartholomew suggests. The FDA has implemented a revised Nutrition Facts label with a separate line item for added sugars.
• Add less (or no) sugar. Cut back on how much sugar you add to your morning coffee (start with half the amount) and other drinks. Avoid adding syrups and sugar to foods like pancakes, cereal, or oatmeal.
• Increase water intake. Limit how much soda, sports drinks, and juice you drink each day. Replace with water to stay hydrated all day long.
• Eat fresh fruit. Try adding sliced fruit to your cereal, oatmeal, and yogurt instead of sugar. Plus, eating fresh fruit as a snack will help satisfy your sweet tooth without affecting your daily added sugar intake.
• Add extracts to recipes. Use vanilla or almond extract when baking to help curb the amount of sugar. Other options include citrus flavors and spices like nutmeg to add flavor.
• Try sugar substitutes. Bartholomew also recommends swapping sugar for a natural replacement like honey or agave. "Added sugars can be more easily avoided when you have the right tools," Bartholomew says. This way, when your sweet tooth strikes, you'll be armed with an ingredient that won't leave your palette feeling deprived.
• Skip high-sugar desserts. While a nightly piece of pie is tempting, replace it with other options like baked cinnamon apples or dark chocolate (at least 70 percent cacao). You'll enjoy a sweet treat after dinner minus the added sugars.