Understanding Acute vs. Chronic Inflammation: What's Healthy and What's Harmful?

Not all inflammation is bad! Here's how know what's healthy and what's harmful.

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Photo: Getty Images / raquel arocena torres / horillaz

Anti-inflammatory diets and eating approaches continue to grow in popularity, and the hype is for good reason. One type of inflammation, known as chronic inflammation, is linked to almost all chronic conditions Americans are facing or trying to prevent including obesity, type 2 diabetes, heart disease, cancer, autoimmune disorders, and joint issues. But there's another type of inflammation, called acute inflammation, that's healthy. In fact, the body relies on it to heal and protect itself.

Both acute and chronic inflammation are immune system responses with very different impacts on health. So how do you distinguish between acute and chronic inflammation? Here's a quick overview.

Read More: 5 Things You Shouldn't Do When Trying to Decrease Inflammation—and 5 Things You Should

What is Acute Inflammation?

Sometimes referred to as "good" inflammation, acute inflammation is temporary and designed to help the body heal or fight off a pathogen. Onset is quick and usually triggered by an injury like a cut, bruise, burn or sprain or when the body is exposed to or infected by pathogens like bacteria or viruses. When the immune system initiates this acute inflammatory response, the body diverts blood flow and white blood cells to the area hurt or under attack.

Signs of acute inflammation are usually easy to recognize and include things like swelling, redness, pain, fever, or pus. While bothersome for a few days, these symptoms indicate the immune system is working as it should, and most acute inflammation slowly dissipates and goes away within a few days to weeks.

Antibiotics or other treatments may occasionally be needed to help the natural inflammatory process along, but the key is that the inflammation goes away. This gives the immune system a break to rest and regroup before being called into action again, and it is important for the immune system to stay healthy and function effectively later when needed.

What is Chronic Inflammation?

Chronic inflammation is usually triggered by irritants and foreign compounds such as chemicals, additives, and allergens found in food and the environment, but lifestyle factors such as ongoing stress, a lack of quality sleep, poor diet, a sedentary lifestyle, and excess body fat can also be irritants. These compounds or irritants trigger a low-level inflammatory response that, unlike acute ones, doesn't go away unless changes to lifestyle, diet, or environment are made.

The ongoing inflammatory response slowly leads to an overworked immune system. This impacts its ability to heal and protect the body, but it also begins to impact the proper functioning within systems that the immune system regularly interacts with like the endocrine, cardiovascular and nervous systems.

Identifying chronic inflammation is difficult because signs tend to be vague and subtle. Early signs are often things like gas, bloating, changes to digestive habits, stiffness and joint pain, high LDL or low HDL cholesterol, slightly elevated glucose, weight gain or inability to lose weight, and a lack of energy. Existing inflammation may also increase sensitivity to other irritants, intensifying the chronic inflammation within the body and creating a self-perpetuating cascade of effects.

As overall inflammation grows and intensifies, symptoms usually become more noticeable as the body is pushed closer to the onset of a diagnosable health condition or disease. While there are often additional factors at play, like age and genetics, long-term chronic inflammation is partially responsible for conditions like diabetes, high blood pressure, or heart disease, and even dementia and Alzheimer's disease may develop.

How to Keep "Bad" Chronic Inflammation in Check

The good news is lifestyle changes and healthy eating can reduce chronic inflammation! Adding in daily activity, whether it's walking, running or yoga, can help to decrease inflammation, as can other healthy lifestyle habits, like not smoking, cutting back on alcohol, prioritizing quality sleep, and working to decrease life's daily stressors. And an eating approach that minimizes dietary irritants like added sugars and processed foods and emphasizes nutrients and foods that ease inflammation like omega-3's, vegetables, and fruits can go a long way in fighting dangerous chronic inflammation.

See More: 30+ Recipes to Fight Inflammation

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