Over the past several years, awareness has continued to grow recognizing “chronic systemic inflammation” as a major driver of disease. We all know what acute inflammation looks like —redness, heat, swelling (think sprained ankle, cuts, etc). Acute inflammation is a natural, protective process that allows us to heal from injury or infection. Chronic inflammation, in contrast, is less recognizable and can at times be a “silent” process.
Unlike acute inflammation, it can carry on continuously for months or even years. In chronic inflammation, the activated immune system releases a host of compounds including things like inflammatory cytokines and hormones such as cortisol, which over time lead to organ dysfunction and increase the risk of virtually all chronic diseases. Even a condition like depression, which has long been thought of as simply a chemical imbalance in the brain, has more recently been understood to also be linked with inflammation. In many instances, if antidepressants are working for someone it may be largely due to their anti-inflammatory effects.
There are a wide variety of causes of chronic inflammation. In my daily practice with patients, trying to uncover which of those fundamental causes are driving issues for my patient is a key goal. Things like HPA-axis dysfunction, gut dysbiosis and other GI imbalances, poor sleep quality, lack of physical activity, chronic infections, loneliness/emotional issues, and environmental toxicity are among the many things we investigate. Today I will focus on diet as a driver of chronic inflammation.
Diet is one of the most foundational pillars of health. Most people have an understanding that the Standard American Diet, or a “Western diet”, is associated with poor health outcomes. A Western diet is generally high in added sugar and refined grains, vegetable oils, ultra-processed foods and low in fiber and whole foods.
We often hear in the natural health/wellness space that we should consume an “anti-inflammatory diet”. Have you ever stopped to consider what really makes a diet anti-inflammatory? Or how exactly a standard Western diet can drive inflammation? In this article I will review five ways (in no particular order) that dietary choices can lead to chronic systemic inflammation.
#1 An inflammatory gut environment
As you may have heard by now, gut health is critical to our overall health and can be directly correlated with the health of virtually all the major organ systems of the body. One of the (many) variables affecting our gut health is diet. Added sugars, refined grains, alcohol, and food additives are among the food substances commonly found in a Western diet that will promote gut dysbiosis and can disrupt the intestinal barrier.. When the intestinal barrier is leaky (also known as “leaky gut”), the immune system is exposed to more microbes/food proteins/toxins and the immune system becomes chronically activated. Gut health imbalances are some of the most common causes of generalized chronic inflammation, and diet is a major driver.
#2 Blood sugar dysregulation/hyperinsulinemia
A Western diet will raise blood sugar through a variety of mechanisms, and elevated blood sugar is inherently inflammatory. There is a reason that after a meal, as blood sugar rises, the body attempts to bring levels back down in a timely manner using the hormone insulin.
A Western diet often consists of what are known as “high glycemic load” foods. Glycemic load refers to how much blood sugar will rise, on average, for a serving of any given food. This is a highly individual process and can vary greatly from individual to individual, but we still know the worst offenders (things like juice, white rice, bagels, raisins, crackers, etc). The highest glycemic load foods are usually high-carb, low-fiber and low in overall nutritional value. Regularly consuming high glycemic-load foods will lead to oxidative stress and also raise insulin, which overtime can lead to insulin resistance and diabetes. A persistently elevated blood sugar will certainly lead to chronic inflammation.
#3 Vegetable oils/lipid oxidation
Vegetable oils have been maligned within the natural/alternative health space for some time now, most often buried due to their omega-6 content and the implications of the omega-6/omega-3 fatty acid ratio. Omega-6 fatty acids, predominantly arachidonic acid, is a precursor to pro-inflammatory compounds in the body. Omega-3 fatty acids (EPA and DHA) are anti-inflammatory. So there is good reason to pay attention to these fats, and there is some research suggesting that excess omega-6 intake could offset benefits from supplementing with omega-3.
Still, while we certainly don’t want to overdo our omega-6 intake and should prioritize foods high in omega-3 (namely seafood), this is not a satisfactory justification for why we should avoid vegetable oils. If omega-6 fatty acids lead to chronic inflammation, we would anticipate that high omega-6 foods would consistently lead to increased inflammation. However, nuts are quite high in omega-6 yet consistently associated with health benefits in the scientific literature.
But before it sounds like I am defending vegetable oils, this does not leave them innocent. Vegetable oils (safflower, sunflower, soybean, etc), because of their chemical structure, are susceptible to lipid oxidation when cooked at high temperatures or for long amounts of time, leading to the production of compounds known as “polar” compounds. The consumption of polar compounds has been associated with cardiovascular disease. Consumption of heated oils has been shown to induce vascular inflammation, and increase levels of oxidative stress in the body. Restaurants frequently use vegetable oils in their cooking, and unfortunately often at high heats and for long amounts of time—the worst combination. Vegetable oils found in processed foods (e.g. chips) have often been exposed to high heat already by the time you consume the product. They are ubiquitous in our food supply, and an important dietary driver of inflammation.
#4 Excess body fat
Another way a Western diet can drive chronic inflammation is by promoting the accumulation of excess fat—particularly visceral fat. Fat is important, and not all body fat is bad. There are two major categories of body fat: subcutaneous and visceral. Subcutaneous fat is the fat stored just under our skin.This fat is important for protecting our body, temperature regulation, and ensuring we have adequate stores of energy should we have extended periods of time without food (unlikely these days). Visceral fat is the internal/abdominal fat that lines and protects our inner organs. The accumulation of visceral fat is more tightly associated with inflammation and increased risk of chronic disease. Excess calories in fat cells leads to the production of inflammatory compounds that circulate the body.
It’s hard not to accumulate excess body fat on a Western diet. To avoid eating too many calories, you want to eat a lot of fiber, protein, and nutrient-dense foods. A Western diet is headlined by nutrient-poor, carb-heavy foods low in fiber. Additionally, a Western diet consists of “hyperpalatable” foods that override the brain’s normal appetite regulation mechanisms and encourage—almost compel—overeating. Food scientists have quite literally crafted processed foods to contain just the right combination of things like sweetness, saltiness, and crunch in such a perfect combination that they become irresistible. Which is why it’s so critical to keep that stuff out of sight, out of mind!
#5 Food allergies/intolerances
The last factor I’ll discuss is food allergies and intolerances. This diet-inflammation connection is not specific to a Western diet, and can involve some foods that may be otherwise perfectly healthy. For a variety of reasons, some individuals may experience an abnormal immune response from consuming certain foods. The “top 8” most common allergenic foods include peanuts, tree nuts, eggs, milk, wheat, shellfish, fish and soy. In our practice, we can perform testing to help determine which foods may be causing chronic immune activation for any given individual. Many times it might simply be worth doing an elimination diet in lieu of testing, and those top eight allergens would be the place to start in terms of foods to try eliminating.
Hopefully now you feel you have a better sense for the connection between diet and inflammation, and which aspects of the “SAD” (Standard American Diet) are perhaps the most problematic. By avoiding the pitfalls outlined above, you can begin to see benefits simply from addition by subtraction. But on top of that, by instead regularly and frequently consuming whole foods like fruits and vegetables, you’ll not only avoid these issues but also consume high levels of nutrients and phytochemicals which have been shown to have antioxidant and antiinflammatory properties. And your future self will thank you as you reduce the risk of diseases associated with systemic chronic inflammation.
Andrew Graham is a board-certified Family Nurse Practitioner licensed to practice in the State of Arizona. He completed his Master’s in Nursing from Boston College after earning a Bachelor’s of Science in Nutritional Science from Brigham Young University. Before receiving his conventional training, he discovered and began studying functional and integrative medicine many years prior after dealing with health issues himself. Andrew is committed to thoroughly investigating patient’s health concerns in an effort to identify root causes, and then using the most effective combination of conventional and integrative modalities in order to optimize health and well-being. Particular interests include gut health, nutrition, blood sugar issues, hormonal imbalances and longevity medicine.