Do Carbohydrates Cause Inflammation? The Truth About Good vs. Bad Carbs

December 6, 2025 •

3 min read

Recent studies have shown that excessive intake of processed sugars and refined carbohydrates is a significant contributor to inflammation in the body. For decades, the public has debated whether carbohydrates cause inflammation, but the answer is more nuanced than a simple yes or no.

Quick Summary

This article explores the complex relationship between carbohydrate consumption and inflammation, distinguishing between the negative effects of refined carbs and the anti-inflammatory benefits of complex carbohydrates. It outlines the specific mechanisms by which different carb types influence the body's inflammatory response, offering clear dietary guidance.

Key Points

Refined vs. Complex Carbs: The inflammatory effect of carbohydrates depends entirely on their type. Refined, processed carbs promote inflammation, while complex, fiber-rich carbs can help reduce it.
Blood Sugar Regulation: High glycemic index (GI) foods like refined carbs cause rapid blood sugar spikes, triggering the release of pro-inflammatory cytokines.
Gut Health Connection: Fiber from complex carbohydrates feeds beneficial gut bacteria, which produce anti-inflammatory compounds, unlike the harmful effects of a high-sugar diet.
Dietary Strategy: To lower inflammation, focus on replacing processed foods and sugary drinks with whole grains, vegetables, and legumes to increase your intake of beneficial fiber and antioxidants.
Hidden Inflammatory Sources: Be aware of hidden refined carbs and added sugars in common processed foods, sauces, and packaged snacks.

Understanding the Link Between Carbs and Inflammation

Inflammation is a natural and necessary biological response to injury or infection. However, chronic low-grade inflammation, often triggered by diet and lifestyle, can contribute to serious health issues like heart disease, diabetes, and obesity. When we ask, "do carbohydrates cause inflammation?" we must clarify which carbohydrates we are talking about.

Carbohydrates are categorized into refined (simple) and unrefined (complex). Refined carbohydrates, which lack fiber, vitamins, and minerals due to processing, are rapidly digested. This leads to quick increases in blood sugar and insulin, promoting inflammation. Complex carbohydrates, found in whole grains, vegetables, and legumes, are digested slowly, providing a gradual release of glucose that prevents the blood sugar fluctuations associated with inflammation.

The Negative Impact of Refined Carbohydrates

Refined carbohydrates contribute to inflammation through several mechanisms:

Blood Sugar Spikes: Rapid increases in blood sugar from refined carbs can trigger the release of pro-inflammatory cytokines.
Advanced Glycation End Products (AGEs): Excess sugar forms AGEs, compounds that drive inflammation and oxidative stress.
Gut Microbiome Dysbiosis: High sugar intake negatively alters gut bacteria balance, potentially increasing gut permeability and allowing toxins into the bloodstream.
Insulin Resistance: Frequent blood sugar spikes can lead to insulin resistance, where high insulin levels can signal inflammation.

The Anti-Inflammatory Power of Complex Carbohydrates

Complex carbs, rich in fiber, are beneficial for reducing inflammation.

Fiber's Role in Regulation: Soluble fiber in complex carbs slows sugar absorption, preventing inflammatory blood glucose spikes.
Nourishing the Gut Microbiome: Fiber acts as a prebiotic, supporting beneficial gut bacteria that produce anti-inflammatory short-chain fatty acids (SCFAs).
Antioxidant Benefits: Whole food carb sources like fruits and vegetables contain antioxidants that fight oxidative stress, a factor in inflammation.

Refined vs. Complex Carbs: A Comparison Table


Feature	Refined (Simple) Carbohydrates	Complex (Unrefined) Carbohydrates
Processing	Heavily processed, stripped of fiber and nutrients.	Minimally processed, contains natural fiber, vitamins, and minerals.
Glycemic Index (GI)	High GI, causing rapid blood sugar spikes.	Low GI, leading to a slow and steady release of glucose.
Associated Inflammation	Linked to chronic low-grade inflammation.	Associated with a reduction in inflammatory markers.
Examples	White bread, pastries, white rice, sugary drinks.	Oats, quinoa, legumes, sweet potatoes, whole fruits.
Gut Health	Can lead to gut microbiome dysbiosis.	Promotes a healthy and diverse gut microbiome.

Practical Steps to Reduce Inflammation

Improving carbohydrate quality is key to managing inflammation. Focus on replacing refined, processed options with nutrient-dense whole foods.

Embrace Whole Grains: Choose brown rice, quinoa, and whole-wheat instead of white varieties for more fiber and sustained energy.
Boost Fiber Intake: Increase consumption of legumes, vegetables, and fruits.
Read Labels Carefully: Watch for hidden sugars and refined grains in packaged goods.
Prioritize Low GI Foods: Select foods that minimize blood sugar fluctuations.
Eat Smart, Not Less: Focus on choosing healthy carbs for energy and nutrients.

Conclusion: Quality Over Quantity

The impact of carbohydrates on inflammation depends on their type. Processed and refined carbs contribute to chronic inflammation, while complex, whole-food carbohydrates can help reduce it. By choosing healthier carb sources, you can improve inflammatory markers and support overall health. It's about understanding and utilizing carbohydrates wisely in an anti-inflammatory diet. For further information, the National Institutes of Health website at National Institutes of Health (NIH) is a valuable resource.

Frequently Asked Questions

Yes, an anti-inflammatory diet should include complex carbohydrates from whole foods. Focus on sources like whole grains, legumes, vegetables, and fruits, which are rich in fiber and nutrients that help reduce inflammation.

The Glycemic Index (GI) measures how quickly a food raises blood sugar levels. High GI foods lead to rapid spikes, which can trigger inflammatory responses. Choosing low GI foods helps maintain stable blood sugar and minimizes inflammation.

No, not all sugars are equal. Added sugars and high-fructose corn syrup in processed foods are the main culprits. Natural sugars found in whole fruits are less likely to cause inflammation because they are paired with fiber and other beneficial nutrients.

No. While very low-carb diets can reduce inflammation in some cases, focusing on the quality of carbohydrates is often more effective and sustainable for long-term health. Prioritizing complex carbs over refined ones is the key.

Some of the worst inflammatory carbs include white bread and pasta, pastries, sugary cereals, and sugar-sweetened beverages. These are all examples of refined, high-sugar foods that promote inflammation.

A diet high in fiber from complex carbs promotes a healthy gut microbiome, which produces anti-inflammatory compounds. Conversely, high-sugar diets can disrupt this balance and increase gut permeability, leading to systemic inflammation.

For most people, yes. Whole grains contain fiber and nutrients that help regulate blood sugar and fight inflammation, unlike refined grains found in white bread and pasta. However, some individuals with specific sensitivities, like celiac disease, may need to avoid gluten-containing grains.