Celebrities, clean-eating Instagrammers, and all manner of internet health “experts” are throwing around the word "inflammation." This natural bodily process, they claim, is at the root of our constant fatigue, anxiety, depression, you name it — and you probably need some very weird and specific supplements or a ton of green juice to solve it. What's more, these crunchy internet health gurus are also spreading rumours that inflammation is responsible for allergies, diabetes, and ADHD. The truth is that there's really no research supporting these types of fear-mongering claims so popular in certain internet haunts, though it is also true that inflammation can be a problem. In short, inflammation is kind of confusing, but here's what you really need to know about it: In most circumstances, inflammation is a totally normal and healthy immune reaction. Inflammation is the body’s natural response to infection or injury, explains Andrew Miller, MD, at Emory University, who has been studying the way this response affects our mental health. When your nose gets all runny when you have a cold, that’s thanks to inflammation. This is your body's way of trying to stop the germs from spreading by trapping them in your snot and flushing them out. When the area around a paper cut gets red and puffy, that’s inflammation protecting you from an infection at the wound site. When, say, the arches of your feet aren’t supported and you develop the pain and heat in your heel of plantar fasciitis, that’s also inflammation. All of these responses, while unpleasant, are signs that your immune system knows there’s a problem and is sending white blood cells to support the healing process. But the key is that those inflammatory responses go away. “If [inflammation] becomes chronic or persistent,” explains Dr. Miller, “it can do significant damage to a number of systems in the body.” This is the case for autoimmune disorders, such as thyroid disorders, as well as inflammatory bowel diseases and rheumatoid arthritis. Treatments that specifically target inflammation (e.g. steroids) are the key in these more serious situations. But, for the rest of us, inflammation isn’t a disease on its own — though, and this is where it gets tricky, there is evidence that even in the absence of a specific disease, inflammation may still be long-lasting for some people. In this case, we're talking about a complex, poorly-understood type of inflammation. Scientists aren't sure exactly where it comes from, but we do know that stress (including repeated stressful interactions with our fellow humans) seems to be a major cause of this kind. “We don’t deal with pathogens [as much] today. We deal with people,” Dr. Miller says. But the problem is our immune systems don’t realise that a stress-inducing interaction with our manager at work or that one super racist Facebook friend isn't truly a threat to our survival, as much as it may feel like it in the moment. And if you're repeatedly stressed out by people every day, as many of us are, this can bring on a kind of low-grade chronic inflammation that can make it harder for other illnesses, such as heart disease and cancer, to improve. Dr. Miller says the discovery of this stress-inflammation link was a “game-changer.” And, recently, his work has found that issues such as depression may be linked to inflammation via this stress mechanism. Evolutionarily, he says, this may have functioned as a cue for our ancestors to seek rest and alone time when they needed to heal. But today, we don't necessarily listen to that cue. But, as interesting as this is, that still doesn’t mean that all of us have to be worried about chronic inflammation — or that it’s really the cause of every awful thing we feel. “Inflammation is not the root of all evils, but it is the root of evil for some people,” says Dr. Miller. For example, Dr. Miller suspects that having higher levels of inflammation may make it more challenging to treat clinical depression. And those of us who are particularly stressed and overweight (another major cause of inflammation) are more likely to have an issue that may manifest as extreme fatigue, depression, anxiety, or tummy troubles. If you’re worried about your inflammation level, your doctor can do a blood test for something called c-reactive protein (CRP). This protein is a marker of inflammation and is traditionally used to help diagnose inflammatory diseases, such as rheumatoid arthritis. If it does look like you have a high level of systemic inflammation, it turns out that the “treatment” is really just the good advice we’ve all been told a thousand times so far: Regular exercise, a balanced, nutritious diet, yoga, and meditation have all been shown to reduce CRP levels. Although some internet health gurus may advocate for a specific “anti-inflammation” diet, there’s no need to go overboard, cutting out peppers here and corn there; staying active and eating well (most of the time) is enough. Otherwise, there is some research to suggest that incorporating aspects of the Mediterranean Diet — which favors lean protein, veggies, beans, nuts, legumes, and olive oil — can help keep inflammation under control. But, as usual, there’s no need to slam the green potions.