Added sugar drives chronic, low-grade inflammation. It signals the body to make pro-inflammatory molecules. It forms harmful AGEs, loosens the gut wall and adds body fat. That slow burn is tied to obesity, diabetes and heart disease.
It’s no secret that sugar is bad for you. It rots your teeth, packs on pounds around your belly, and gives you zero nutrition. Sadly, these are the least of sugar’s crimes. The biggest reason to stop eating sugar is that it is one of the most pro-inflammatory foods. Current research suggests that chronic, body-wide inflammation is associated with many modern diseases, like obesity, diabetes, and heart disease. So what role does a high-sugar diet play in chronic inflammation? In this article, we’ll dig into this and much more.
- So, what is inflammation?
Inflammation is part of the body’s natural healing process.
Acute inflammation develops quickly in response to an injury or infection. This type of inflammation tends to be good. It’s your body’s way of trying to fight off more damage while it jump-starts healing. It usually lasts a few days to a few weeks.
Chronic inflammation is long-term inflammation that lasts for months or years. It has several causes, including unhealthy lifestyle factors like diet. Over time, chronic inflammation can raise your risk of serious diseases.
Some foods, like sugar, can also cause inflammation in the body, which is normal. However, eating too many inflammatory foods may cause chronic low-grade inflammation. This can cause serious health problems, such as heart disease, diabetes, and cancer.
- How does a high-sugar diet lead to chronic inflammation?
People who eat diets rich in refined sugar may be raising their risk of chronic inflammation. Research suggests that when people eat and drink less sugar, inflammatory markers in their blood go down.
A high sugar diet can harm your health. It can raise the risk of chronic diseases, weight gain, and tooth decay. It can also result in chronic inflammation. In chronic inflammation, the body’s immune system switches on and damages healthy cells.
Inflammation from lifestyle factors can contribute to a range of diseases. These factors include obesity, smoking, and a sedentary (inactive) life. The diseases include heart disease, diabetes, rheumatoid arthritis, and Alzheimer’s.
- Is too much added sugar linked to inflammation?
A lot of research has looked at how sugar causes inflammation. Diets high in added sugar are thought to signal the body to make pro-inflammatory molecules. Over time, that can create a state of chronic, low-grade inflammation and lead to trouble later. Sugar also drives the making of free fatty acids in the liver. When the body digests these free fatty acids, the compounds left over can trigger inflammatory processes.
Different kinds of sugar may add more or less to inflammation. For instance, some research has suggested that fructose may cause more inflammation than glucose. However, a systematic review found no difference in the inflammation from fructose and glucose. So more research is needed.
Also, the researchers saw no differences in inflammatory factors between the groups that ate high fructose corn syrup vs. sucrose. The sample sizes were small, and the quality of the studies was low. So more research is needed to confirm these findings.
Below are some of the common signs and symptoms of chronic inflammation:
- depression, anxiety, and other mood disorders
- body pain
- constant fatigue and insomnia
- constipation, diarrhea, acid reflux, and other digestive issues
- weight gain
- frequent infections
People with chronic inflammation may have a higher risk of diabetes, depression, and dementia.
Chronic inflammation in older adults may also be linked to a higher risk of death. Doctors are working on ways to reduce chronic inflammation.
- How does added sugar affect your body?
When you eat too much added sugar and refined carbohydrates, a few things change in your body. These changes help explain why a diet high in sugar can lead to chronic, low-grade inflammation.
- Excess production of AGEs: Advanced glycation end products (AGEs) are harmful compounds. They form when protein or fat combines with sugar in the bloodstream. Too many AGEs lead to oxidative stress and inflammation.
- Increased gut permeability: Bacteria, toxins and undigested bits of food can more easily leak out of the gut and into the bloodstream. This could potentially lead to inflammation.
- Higher “bad” LDL cholesterol: Too much LDL cholesterol has been associated with higher levels of C-reactive protein (CRP). CRP is a marker of inflammation.
- Weight gain: A diet rich in added sugar and refined carbohydrates can lead to weight gain. Excess body fat has been linked to inflammation, partly due to insulin resistance.
It is important to note that sugar alone is unlikely to cause inflammation. Other factors like stress, medication, smoking, and eating too much fat can also lead to inflammation.
- Is natural sugar linked to inflammation?
It’s important to note that added sugar and natural sugar are different. Added sugar is removed from its original source. Then it is added to foods and drinks to sweeten them or make them last longer on the shelf.
Added sugar is found mostly in processed foods and drinks, though table sugar also counts as added sugar. Other common forms include high-fructose corn syrup (HFCS), sucrose, fructose, glucose, and corn sugar.
Among US adults, around 13% of total calories come from added sugar. This is high, given that government guidelines advise that no more than 5% to 15% of calories should come from solid fats and added sugar combined.
Natural sugar has not been linked to inflammation. In fact, many foods with natural sugars, such as fruits and vegetables, may be anti-inflammatory. Natural sugars are those found naturally in foods. Examples include fructose in fruit and lactose in milk and dairy products.
Eating natural sugars should not be any cause for concern. That’s because the body handles them very differently from added sugar when they are eaten and digested.
What lifestyle changes reduce inflammation?
It is important to know what we can do to lower the inflammation in our bodies. Here are some simple tips to help reduce inflammation:
- Adopt a low glycemic diet: High sugar intake is linked to chronic inflammation. It is also linked to the risk of stroke, coronary heart disease, and type 2 diabetes. Soda, refined carbohydrates, and high fructose corn syrup are foods that can promote inflammation.
- Read food labels: If you are unsure about certain products, get in the habit of reading food labels. Watch for ingredients like sucrose, glucose, high-fructose corn syrup, maltose, and dextrose.
- Skip refined grains and bread: In chronic pain, gluten and gliadin drive a leaky gut and autoimmune trouble. Build meals around protein, such as red meat and fish, and vegetables instead. That helps control blood sugar and inflammation.
- Eat more fruits and vegetables: Fruits and vegetables contain antioxidants, vitamins, and minerals. These can protect against and reduce inflammation in the body.
- Eat lots of antioxidant-rich foods: Fill your plate with foods rich in antioxidants, which naturally help fight inflammation. These include nuts, seeds, avocados, oily fish and olive oil.
- Keep active: Regular exercise can help protect against weight gain and inflammation. That means both aerobic and resistance (strength) exercise.
- Manage stress levels: Learn to manage stress with relaxation techniques, and even exercise. This can help reduce inflammation.
- Add curcumin to food: Curcumin is a part of turmeric. It improves several inflammatory diseases.
- Get enough fiber: Researchers have shown an association between high fiber diets and lower inflammatory factors. These include TNF-alpha and interleukin-6.
- Drink green and black teas: Scientists have associated compounds in green and black teas with lower C-reactive protein in the blood.
- Eat more nuts: Almonds and other nuts may help lower the risk of cardiovascular disease and diabetes. Cardiovascular diseases, such as atherosclerosis, are pro-inflammatory states. Diabetes is a chronic inflammatory disease.
- Add fish oil to the diet: Omega-3 fatty acids are associated with lower levels of inflammatory factors in the blood. These include C-reactive protein, interleukin-6, and TNF-alpha.
- Does sugar cause inflammation?
Inflammation is a critical part of metabolic syndrome. However, chronic low-grade inflammation leads to diseases. These include type 2 diabetes, atherosclerosis, non-alcoholic liver diseases, and gout. Research suggests that eating lots of sugar can lead to chronic inflammation.
In the United States, the amount of high fructose corn syrup people eat rose from 1978 to 1998 and then leveled off, according to the Nationwide Food Consumption Surveys. As more people learn the risks of added sugar, sugar intake in the U.S. has been falling. Still, people are eating too much sugar.
There are several things you can do to help fight inflammation. Exercise regularly and manage your stress well. Also, cut down on processed foods and drinks, and choose whole foods. Limit added sugar and refined carbohydrates.
Frequently asked questions
What are the signs of too much sugar?
A diet high in added sugar shows up as weight gain, especially around the belly. It also shows up as tooth decay and chronic, low-grade inflammation. The signs of that inflammation include body pain, constant fatigue and insomnia, depression and anxiety, digestive trouble such as constipation, diarrhea or acid reflux, and frequent infections. Left alone, it raises the risk of diabetes, heart disease and dementia.
Does cutting out sugar reduce inflammation?
Yes. When people eat and drink less sugar, the inflammatory markers in their blood go down. Cutting added sugar works best alongside the other steps on this page. These include a low-glycemic diet, reading labels for sucrose, glucose, high-fructose corn syrup, maltose and dextrose, more fiber, regular exercise and managing stress. Natural sugar in whole fruit is not the problem.
What are the worst inflammatory foods?
The foods that promote inflammation most are soda, refined carbohydrates and high-fructose corn syrup. So are the processed foods and drinks where most added sugar hides. Added sugar forms harmful AGEs. It loosens the gut wall so bacteria and toxins reach the bloodstream. It also adds body fat that feeds insulin resistance. Among US adults, around 13% of calories now come from added sugar.
Related reading
References
- Medical News Today (2017): Everything you need to know about inflammation. Retrieved from https://www.medicalnewstoday.com/articles/248423.php
- Healthline (2017): Does Sugar Cause Inflammation in the Body? Retrieved from https://www.healthline.com/nutrition/sugar-and-inflammation
- Medical News Today (2019): Does sugar cause inflammation in the body? Retrieved from https://www.medicalnewstoday.com/articles/326386.php
- Mindbodygreen (2019): The Real Reason You Should Quit Sugar + How To Cut It Out Of Your Life For Good. Retrieved from https://www.mindbodygreen.com/0-24763/the-real-reason-you-should-quit-sugar-how-to-cut-it-out-of-your-life-for-good.html
- NCBI (2014): Chronic inflammatory disorders and risk of type 2 diabetes mellitus, coronary heart disease, and stroke: a population-based cohort study. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/24970784
- NCBI (2019): Chronic Inflammation. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK493173/
- Greatist (2019): Does Sugar Actually Cause Inflammation? Retrieved from https://greatist.com/health/sugar-and-inflammation
Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP
Interventional pain physician, addiction medicine specialist and obesity medicine diplomate.
Licensed in Missouri and Illinois.
Last reviewed June 18, 2026
