Added sugars are found in processed and sugar-sweetened foods and beverages. The average daily sugar consumption in the United States is 19 teaspoons (76 grams) for men and 15 teaspoons (60 grams) for women. Almost half of adults in the U.S. drink sugar-sweetened beverages, like soda, daily.
The Dietary Guidelines for Americans recommend limiting added sugar consumption to less than 10% of total daily calories—about 12 teaspoons of added sugar or less for a 2,000-calorie diet.
Eating too much sugar can contribute to inflammation and lead to chronic conditions, including type 2 diabetes, cardiovascular (heart and blood vessel) diseases, inflammatory bowel disease (IBD), and other inflammation-driven diseases.
The immune system protects the body against health threats like pathogens (disease-causing bacteria and viruses), overuse, injury, and toxic chemicals. Inflammation results from the immune response; it’s how the immune system communicates with other cells to help the body heal.
Inflammation can appear in different ways. It can be:
- Local (in one area) or systemic (affecting the whole body)
- Acute (short-term) or chronic (long-term)
- Low-grade (not detectable in tests), which is not severe inflammation but is long-lasting
Short-term inflammation is important for healing. Once the body has eliminated the health threat, inflammation resolves. However, when inflammation becomes chronic, it can cause organ dysfunction and damage.
Chronic Inflammation Causes and Diagnosis
Chronic inflammation can occur for many reasons. Some infection-causing bacteria or viruses are resistant to medications, meaning they remain in the body, promoting inflammation. Another cause of chronic inflammation is autoimmune disease, which occurs when the body cannot recognize its own cells and has an immune response to eliminate them.
Chronic inflammation can also be metabolic inflammation (meta-inflammation). This occurs due to metabolic imbalances such as excess abdominal fat (commonly known as belly fat) or conditions like high blood fat levels, prediabetes, and diabetes.
To measure chronic inflammation, healthcare providers may perform a blood test to look for these common inflammation markers: C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, and serum amyloid A.
High sugar consumption can contribute to inflammation in several ways, such as promoting insulin resistance, increasing abdominal fat, and decreasing gut health.
Contributes to Insulin Resistance
Insulin is a hormone the body produces to lower blood sugar levels. Regularly eating high amounts of sugar causes excessive insulin production. This can cause the cells to become less responsive to insulin over time, leading to insulin resistance, which is associated with inflammation.
Increases Abdominal Fat
Regularly eating high amounts of sugar can increase abdominal fat, which can cause inflammation. A large study showed that drinking more sugar-sweetened beverages, such as soda, was associated with increased abdominal fat.
Other research has shown people with increased abdominal fat are likely to have higher levels of inflammatory markers, including CRP.
Disturbs the Gut Barrier
Eating too much sugar can reduce beneficial bacteria and increase harmful bacteria in the gut, disrupting the gut barrier. This barrier is selective; it allows certain substances to enter the bloodstream while keeping others out. When the barrier cannot function properly, unwanted substances can enter the bloodstream, leading to low-grade inflammation.
Chronic inflammation can increase the risk of or worsen several health conditions. Sugar-induced inflammation is associated with conditions like:
Prediabetes and Diabetes
A research review found that regularly drinking sugar-sweetened beverages increased the risk of prediabetes. These participants also had an increased risk of high CRP levels.
Another study showed that sugar-sweetened beverage consumption was associated with seven inflammatory molecules but not CRP. Two of these markers were linked to a significant increase in the risk of type 2 diabetes.
Cardiovascular Diseases
Several research reviews found that drinking high amounts of sugar-sweetened beverages is associated with a higher risk of cardiovascular (heart and blood vessel) conditions. These include hypertension (high blood pressure), stroke, and death from heart disease.
Inflammatory Bowel Disease (IBD)
Inflammatory bowel disease (IBD) is characterized by inflammation in the gut. Diet can greatly influence the course of the disease. One large study found that daily consumption of more than one sugar-sweetened beverage increased the risk of Crohn’s disease, which is a type of IBD.
Another study showed that participants who drank more than seven sugar-sweetened beverages weekly were at increased risk of high inflammatory markers, including CRP, compared to people drinking two or fewer sugar-sweetened beverages weekly. Excess consumption of these beverages also caused more frequent emergency visits.
Rheumatoid Arthritis (RA)
Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation and pain. It is more prevalent in women.
One study found that drinking more than one serving of sugar-sweetened soda daily increased the risk of seropositive rheumatoid arthritis (a form of the disease confirmed with antibodies) compared to drinking none or less than one soda daily.
Depression
Depression is one of the most common mental health conditions, and diet is thought to be a contributing factor.
A research review showed that high sugar-sweetened beverage consumption increased the risk of depression. Participants who drank 2 cups of soda daily had a 5% higher risk of depression compared to non-soda drinkers.
In addition to increasing inflammation risk, high sugar consumption is associated with decreased brain function, dental caries, high uric acid levels (which can cause gout or kidney stones), and fatty liver.
Added sugar is not considered the same as sugar naturally found in foods such as fruits, vegetables, and dairy.
Many studies report that fruit and vegetable consumption improves inflammation. One research review also showed that regularly eating fruits and vegetables decreases CRP and TNF-α levels. The Dietary Guidelines for Americans recommend consuming at least three servings of vegetables and two servings of fruits per day to support health.
Other foods and dietary patterns can also worsen inflammation. These include:
- Ultra-processed foods: These foods are high in sugar, as well as saturated and trans fats, which can contribute to inflammation.
- Low-fiber diet: Fiber supports blood sugar control, weight management, and digestive health, which can help prevent inflammation. A diet containing more processed foods is likely to be low in fiber, which may cause higher levels of inflammatory markers.
- Diet lacking essential nutrients: A balanced diet of nutritious foods provides many antioxidant vitamins, minerals, and compounds that help remove harmful substances that can contribute to inflammation. A diet lacking these nutrients can lower your defenses against inflammation.
- High glycemic index diet: Foods with a high glycemic index can cause a sudden increase in blood sugar levels, contributing to insulin dysfunction, abdominal fat, and inflammation over time. Choosing low glycemic index foods can help stabilize your blood sugar levels.
The Dietary Guidelines for Americans recommend limiting sugar intake to 10% of daily calories. If you consume 2,000 calories, you should limit your sugar intake to 50 grams (12 teaspoons).
The American Heart Association recommends consuming less sugar. It suggests limiting sugar intake to 36 grams (9 teaspoons) or 150 calories for men and 25 grams (6 teaspoons) or 100 calories for women.
Here are a few tips to reduce your added sugar intake:
- Read Nutrition Facts labels: When buying packaged foods, check the Nutrition Facts label to see the sugar content per serving and the Daily Value percentage. You can choose products that show 5% or less for added sugars.
- Plan your meals: Planning ahead can help ensure you use low-sugar alternatives when you’re busy and don’t have time to consider the sugar content of food.
- Consume your highest sugar sources less often: Most people’s biggest source of added sugar is sugar-sweetened beverages. One can of soda has more than 40 grams of sugar. If you drink two sodas daily, consider reducing it to one to reduce your sugar intake significantly. From there, try having only one soda per week or only enjoying one occasionally.
- Choose unrefined sugar sources: Satisfy your sugar cravings with naturally sweet foods, like fruit, which contain natural sugars and other nutrients that can benefit your health.
A balanced diet rich in nutrient-dense foods can support your body by preventing chronic inflammation. Foods and lifestyle changes that can help prevent and manage inflammation include:
- A balanced diet: A diet rich in nutritious foods containing fiber, vitamins, minerals, antioxidants, and heart-healthy unsaturated fats can help prevent inflammation. Eating more whole grains, fish, fruits, vegetables, nuts, seeds, and legumes while limiting processed foods can help create a balanced and nutritious diet.
- Regular physical activity: Exercise has been shown to reduce levels of inflammatory markers. The World Health Organization recommends that adults get 150 minutes of aerobic exercise and do strength training twice weekly to support overall health.
- Sleep: Lack of sleep and low-quality sleep can contribute to inflammation. Research shows that sleep-related conditions are associated with a higher systemic inflammation index.
Nutrition may prevent or worsen inflammation. A nutrient-dense can help prevent inflammation, while a diet high in sugar, ultra-processed foods, saturated and trans fats, and processed meats can contribute to inflammation.
High-sugar diets can contribute to insulin resistance, increase abdominal fat, and weaken the gut barrier, all of which can contribute to inflammation. You can reduce sugar intake by checking Nutrition Facts labels, meal planning, and opting for natural sugars, like fruits.
