Inflammation is an important physiological process and results in chemical reactions that increase blood flow for healing, help ward off infection, and trigger pain signals that warn of injury. But too much inflammation exacerbates various chronic conditions, including Alzheimer disease, type 2 diabetes, heart disease, inflammatory bowel disease, chronic obstructive pulmonary disease, cancer, and chronic pain, as well as autoimmune diseases including rheumatoid arthritis, lupus, and scleroderma.
“Inflammation is often compared to fire,” noted University of Wisconsin Integrative Health. “In controlled amounts, there is no question that fire keeps us warm, healthy, and protected, but when there is too much fire, or if fire gets out of control, it can be destructive. But a fire does not need to be big to cause damage.”
They added, “It is now understood that low-grade chronic or ongoing inflammation that is below the level of pain, can contribute to many chronic health problems and can itself become a disease. This low-grade inflammation can keep the body’s tissues from properly repairing and also begin to destroy healthy cells in arteries, organs, joints, and other parts of the body.”
To help keep the in vivo inferno in control, here are some evidence-based dietary tips on maintaining a low-inflammation diet.
Watch those fats
Dietary fatty acids can increase inflammation by increasing body weight, adding adiposity, and changing lipid compositions in the plasma membrane. According to a review article published in the British Journal of Nutrition, saturated fatty acids (SFA) may increase inflammation while polyunsaturated fatty acids (PUFA) may decrease inflammation.
The authors wrote, “There is some evidence, albeit not always consistent, for pro-inflammatory effects of dietary SFA. Much of this evidence comes from either in vitro or cross-sectional studies, and there are limited randomised controlled trial[s] (RCT) examining changes in SFA intake and inflammation in humans.”
They continued, “It has been reported that in overweight men, plasma IL-6, TNF-α and soluble vascular adhesion molecule-1 concentrations decreased after an n-6 PUFA-rich meal, while markers were increased after a SFA-rich meal.”
According to the Arthritis Foundation, eating 3-4 ounces of fish rich in omega-3 fatty acids twice weekly may decrease levels of inflammatory mediators, including C-reactive protein and interleukin-6.
Cutting out carbs
The authors of the aforementioned review also stress the importance of limiting carbohydrates. “Studies have suggested that healthy eating patterns characterised by reduced postprandial glycaemia and lipaemia are associated with reduced concentrations of markers of low-grade inflammation,” they wrote.
With respect to diabetes and heart disease, the repercussions of postprandial glucose levels may be due to inflammation and oxidative stress.
“Importantly, there appears to be no glycaemic threshold for reduction of either microvascular or macrovascular complications. The progressive relationship between plasma glucose and the risk of CVD extends well below the diabetic threshold,” they wrote.
Stocking up on fruits and veggies
The authors of the review added that consuming fruits and vegetables can combat inflammation.
They wrote, “Recent prospective cohort data suggest that improved cognitive function and a reduced risk of age-related neurodegenerative diseases, associated with increased fruit and vegetable intake, may be in large part attributable to intake of specific flavonoids, and may involve an effect on inflammatory processes.”
They added, “In particular, increased consumption of total flavonoids was positively associated with episodic memory in middle-aged adults and with a reduced rate of cognitive decline in adults aged 70 years and over. The anthocyanin group of flavonoids, with certain soft fruits providing the most significant dietary source, has emerged as being particularly potent.”
Here’s an example that will elicit tears. Onions are filled with flavonoid antioxidants—in particular, quercetin that inhibits pro-inflammatory leukotrienes, histamines, and prostaglandins present in osteoarthritis and rheumatoid arthritis. On a related note, quercetin decreases LDL levels and mitigates cancer progression.
Adding more onions to the diet is a recommendation propounded by the authors of a review article published in Redox Biology.
“Use of onion as [a] functional ingredient may be useful to ameliorate the impact of hypercholesterolemia in liver inflammation,” they wrote. “Therefore, the study of the interaction of functional food ingredients with bioactive lipid mediators as part of the hallmark of metabolic impairments is a useful strategy to characterize both their preventive effects and the potential impact of diets on inflammation, oxidative stress and organ dysfunction.”
Because onions come in a variety of shades and tastes, they make excellent culinary accents. Spice up your dishes with raw or sautéed sweet, white, yellow, and red onions. Onions pair particularly well with stir fry, salads, and sandwiches.
Filling up on fiber
Fiber consumption has been shown to decrease levels of CRP, and securing fiber from dietary sources beats supplements hands down.
According to a review article published in Advances in Nutrition, “Fermentable fructose-, glucose-, and galactose-based fibers as well as mixed fibers have shown systemic and local intestinal anti-inflammatory activities when plasma inflammatory markers and tissue inflammation were examined. Similar anti-inflammatory activities have also been demonstrated in some human studies that controlled total fiber intake.”
Additionally, fermentable fibers may serve an immunomodulatory role with respect to the intestinal microbiome/microbial metabolites, thus attenuating local and systemic inflammation.
Set aside the salt
Salt causes fluid retention and exacerbates hypertension. Salt also leads to inflammation, so it’s a good idea to minimize intake whenever possible.
In an experimental study published in the European Journal of Clinical Nutrition, researchers evaluated CRP levels and 24-hour sodium/albumin excretion in 224 patients with primary hypertension. The participants were categorized into the following three groups based on sodium excretion (a proxy for salt intake): a low-salt-intake group (n = 76, mean urine sodium: 111.7 ± 29.1 mmol/24 h), a medium-salt-intake group (n = 77, mean urine sodium: 166.1 ± 16.3 mmol/24 h), and a high-salt-intake group (n = 71, mean urine sodium: 263.6 ± 68.3 mmol/24 h).
CRP and urinary albumin levels were significantly increased in the high-salt-intake group compared with the medium- and low-salt-intake groups, whereas systolic and diastolic blood pressure readings did not vary by salt-intake status. After accounting for covariates, urinary sodium excretion independently predicted CRP and albuminuria. Of note, other research has shown that albuminuria is positively correlated with biomarkers of inflammation.
“These findings suggest that high salt intake is associated with enhanced inflammation and target organ damage reflected by increased albuminuria in treated hypertensive patients independent of any BP effect,” the authors concluded.