For over a decade, scientific research investigating noncommunicable diseases have demonstrated a commonality among seemingly disparate pathologies. What could heart disease, Alzheimer’s, autoimmune disorders, depression, arthritis, and irritable bowel syndrome all have in common? Despite the many differences between each condition, the evidence continues to suggest a key marker appearing in each: biochemical signs of inflammation.
In the human body, the inflammatory process is the natural immune activation that occurs when there is a potential threat–whether that be a wound that needs clotting, a bone that needs healing, or a potential invader that needs to be neutralized. These states of inflammation are healthy and necessary to life. But they also, importantly, are temporary. In fact, there are key cellular signals, including a class of molecules called pro-resolving mediators–that initiate the resolution of inflammation so that the immune response not only brings its heightened activity to a close, but also returns to normal function. However, what science now shows is that sustained states of inflammation are not as functional or benign as naturally occurring inflammation that arises and resolves. The continually elevated immune activity is causing what’s now often deemed “chronic low-grade inflammation,” and markers of its existence are showing themselves to be a risk factor, or component of, many conditions that were previously thought to be unrelated.
The inflammatory process itself is a cascade of biochemical activity involving an array of cell types and molecules, and it can unfold in regions all around the body.
Cardinal signs of inflammation include:
- Redness
- Swelling
- Pain
- Heat
This is easy to visualize when we think of a burn that we might incur on our finger while cooking dinner, or as a dramatic example, the shocking sight of our own knee after an orthopedic surgery. What’s more challenging to visualize, and research, is the inflammation that can occur within the body over long periods of time.
Yet, the same biochemical processes have been detected in these less visible regions.
- The redness associated with inflammation is due to dilated arteries allowing increased blood flow to the site of damage.
- Swelling arises once endothelial cells (flat cells that line the continuous sheet of tissue wrapping around blood vessels and body compartments) have leaked protein and water at the site.
- Immune cells are activated to inflame the site.
Modern research investigating these processes have detected specific signals–molecules, that can communicate to the immune cells–that are secreted at these sites and then promote the inflammatory cascade. As it turns out, these cascades can unfold anywhere in the body because immune cells not only circulate in the blood, but also take residency in tissues and organs themselves. Evolutionarily, these abilities are incredibly beneficial. Modern humans evolved to have hyper-active immune systems, an ability to store surplus energy (fat tissue), and blood that’s quick to coagulate upon insult.
With these ancient processes underpinning much of human immune activity, the inflammatory connection between modern noncommunicable diseases makes sense. But what’s triggering these unrelenting inflammatory cascades?
Part of the answer to that question is a second question: what is even older than the immune system?
Metabolism.
As it turns out, protecting the cell (immunity) is an ancient system. But using energy to fuel cellular activity (metabolism) is even older.
One of the major biological stressors of modern life is the frequent onslaught of nutrition into the gastrointestinal tract. Food, and all of the compounds that arrive with it, is the outside world. Every time a human being eats, it’s a stimulating process not only for the organs involved in digestion and absorption, but also for the immune system. Importantly, approximately 70% of the immune system is housed within the gastrointestinal tract, and it must conduct surveillance at each meal of all food consumed. At every eating opportunity there is a complex interaction between the host immune system and the environment.
Not only is frequent eating associated with increased immune activity, but the food itself is dramatically different from what humans evolved to consume. One of the signatures of the modern food environment is the processed, hyper-palatable meals and food products that are now cornerstones of daily living.
Modern human G.I. tracts are coping with:
- Refined grains
- Alcohol
- Sugar
- Hydrogenated oils
- Emulsifiers
- Preservatives
These not only can cause acute damage during the digestive process, but it perpetuates the low-grade immune activity that can’t resolve–because the offending agent appears three, four, or even five times a day.
Fortunately, there is an antidote to this prevalent issue. As it turns out, one of the most powerful tools to reduce inflammation is also food. Recent evidence has found there to be strong associations between a healthy diet–like the Mediterranean diet–and reduced systemic inflammation. A healthy, anti-inflammatory diet can promote a reduction in fat mass, which has some anti-inflammatory effects on its own, help calm inflammation from powerful molecules in the food itself, and reduce inflammation because the meals contain few irritants.
Benefits from an anti-inflammatory diet include:
- Whole food sources like leafy greens, vegetables, fruits, lean proteins, and healthy fats all have properties that provide the body with amino acids, antioxidants, polyphenols, and other phytonutrient compounds that can neutralize free radicals, quell inflammation, and promote healing.
- Complex carbohydrates like fruits, potatoes, vegetables, and winter squashes are wrapped in a fiber matrix that has been shown to feed the microbiome–the microbial environment in the human colon.
- Feeding these colonies with diverse fuel sources has been associated with increased diversity in the microbiome, which tends to have systemic anti-inflammatory and immune-supportive effects.
When paired with lean proteins and healthy fats like avocado and olive oil, the entire meal provides an array of benefits that help support healthy immune function in the G.I. tract as well as intestinal integrity, fullness, and satisfaction. Additional functional foods, such as probiotic items like kefir and sauerkraut, can also be included to support diversity in the microbiome plus offer beneficial compounds they contain called postbiotics. These bioactive chemicals, like polyphenols, short chain fatty acids, and enzymes, appear to help support the immune system and decrease inflammatory responses.
In contrast to the processed foods that can impair tight junctions, trigger immune responses, and promote potential leaking in the gut, these whole food sources are an example of the natural relationship between environment and host. Thoughtfully tailoring the diet to include predominantly anti-inflammatory, whole foods is a critical component of promoting long-term health not only in the gastrointestinal tract but in the whole body.