There’s a lot of dietary trash talking in the wellness community, and one of the terms that gets thrown around a lot is “inflammatory.”
Popular elimination diets like Whole30 restrict entire categories of food — including legumes, grains and dairy — under the premise that they are “inflammatory.” Another protocol, the ” autoimmune paleo” or AIP diet, similarly claims to reduce inflammation in the gut and “calm inflammation in the body” by eliminating legumes, grains, dairy, eggs, nuts, seeds, vegetables in the “nightshade” family (tomatoes, peppers, potatoes and eggplants), olive oil, certain spices and, ironically, one of nature’s most antioxidant-rich foods: chocolate. Then there’s the fear-mongering against natural plant compounds called lectins, which one newer fad diet claims are both toxic and inflammatory. The solution? Avoid beans and legumes, grains, cashews, squash, nightshade vegetables and, if you must eat wheat, choose white flour over whole wheat. Wait, what?
[See: 8 Food Trends Nutrition Pros Pray Never Return.]
How are any of these diet proponents even measuring inflammation? Did they all get together one night and collectively agree to unleash a smear campaign against grains, legumes, nightshade vegetables and seeds? How did these foods make it onto these elimination diets’ hit lists? Beats me — especially since there is actual science that can tell us what foods or dietary components actually contribute to measurable inflammation in the body, and what a true anti-inflammatory diet looks like.
Meet the dietary inflammatory index, or the DII. It’s an evidence-based tool developed by researchers who reviewed over 1,900 — yes, one thousand nine hundred — research studies that investigated the effect of certain foods or food components on one of six markers of systemic inflammation in the body.
Drawing on this huge body of scientific literature, they generated a list of 45 nutrients and whole foods with a demonstrated effect on inflammation, and assigned each one a score that was weighted in a sophisticated way to account for how many studies backed it up and the quality of those studies. Negative scores imply a food or nutrient has an anti-inflammatory effect, positive scores imply a pro-inflammatory effect and scores at (or close to zero) are neutral.
The most anti-inflammatory nutrients on the DII are various antioxidants, including:
— Flavones, such as the pigments found in the red-purple vegetables of the much-maligned “nightshade” family, including eggplants, peppers and tomatoes;
— Isoflavones, such as those found in soy, the legume that every elimination diet loves to hate;
— Beta carotene, found in orange vegetables, including “lectin-bombs” like winter squash and oh-so-scary pumpkins;
— Flavonols, compounds found in onions, kale, broccoli and fruits like apples and berries;
— Omega-3 fatty acids, which are found in fatty fish, flaxseeds, walnuts and chia seeds; and
— Vitamin C, which is found in citrus fruits, kiwi, strawberries and papaya, as well as those darn nightshades like tomatoes, colored peppers and potatoes.
Certain whole foods like turmeric and ginger also score very favorably on the anti-inflammatory end of the spectrum, as do green and black tea. Magnesium, while not an antioxidant, also held a strong anti-inflammatory score. The foods richest in magnesium are commonly found among those forbidden on fad anti-inflammatory diets, such as tofu, beans, all nuts, seeds, whole grains and chocolate. Fiber also has a strong anti-inflammatory effect — second only to turmeric on the ranking. Eliminate these health-promoting foods at your own risk.
[See: 12 ‘Unhealthy’ Foods With Health Benefits.]
So what foods are inflammatory? Saturated fat and cholesterol score quite high on the pro-inflammatory end of things. Consider this when you encounter a claim that low-fiber, high animal-fat diets like the ketogenic or the carnivore are somehow supposed to reduce inflammation.
The DII not only enables us to look at specific foods’ inflammatory (or not) properties, it can also evaluate any dietary pattern. Diets that are anti-inflammatory will score a negative number, generally somewhere between zero and negative nine, with the lower number representing a more anti-inflammatory dietary pattern. Diets that are very pro-inflammatory will have positive DII scores, with higher numbers representing more inflammatory diets and maxing out at around eight. The researchers who developed the DII have also created a free app that enables you to analyze and score your own diet. (I’m an omnivore who follows a Mediterranean-style diet and scored a negative 4.54 on the quiz.)
Dietary patterns that would probably score well on the DII in terms of being anti-inflammatory include the Mediterranean diet, the DASH diet, Dr. Weil’s anti-inflammatory diet, pescatarian diets (or a vegetarian diet that includes fish), vegetarian diet or fully plant-based (vegan) diets. There are others as well. Following them and those like them, research suggests, may be linked to positive health outcomes, from cancer risk reduction to mental health improvements. For example, women in one study who had the lowest dietary DII scores (indicative of an anti-inflammatory diet) were at lower risk of developing depression than those with higher DII scores. Conversely, pro-inflammatory diet patterns as measured by the DII score have been associated with an increased risk of developing breast cancer in women and colorectal cancer in men and women.
[See: Your Plant-Based Diet Needs These 10 Foods.]
All this to say there is no single “anti-inflammatory diet,” and none of the foods commonly singled out as highly inflammatory by popular fad diets have much evidence basis to back up the claim. While some of these popular elimination diets may indeed produce positive health results, I imagine it’s due to their hard line against sugar and processed foods and enforcement of a high vegetable intake, rather than as a result of their banishing anti-inflammatory foods like lentils, barley or eggplants, which, let’s be honest, most people probably aren’t eating a ton of to begin with. So pick a whatever legit anti-inflammatory diet pattern you like best, and reap the benefits of a sane, diverse diet whose anti-inflammatory potential has some actual science behind it.
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Your Anti-Inflammatory Diet Is Probably Just the Opposite originally appeared on usnews.com