Mixtures of antioxidant nutrients have also been investigated for their effects on inflammation in different population groups. An observational study showed that regular exercise can decrease blood concentrations of inflammatory markers (7). Participants who took antioxidant supplements with beta carotene, vitamin C, and/or vitamin E had reduced C-reactive protein levels similar to those participants who reported higher levels of exercise (180 minutes/week or more) but did not take supplements. As revealed in previous studies, higher body mass index was related to increased levels of several inflammatory markers, such as
C-reactive protein, interleukin-6, and TNF-alpha. A study in patients with a history of sporadic colorectal adenoma found that a combination of alpha-tocopherol (800 mg), beta-carotene (24 mg), vitamin C (1000 mg), vitamin B2 (7.2 mg), vitamin B3 (80 mg), zinc (60 mg), selenomethionine (0.2 mg), and manganese (5 mg) consumed daily for four months had a beneficial effect on markers of inflammation and oxidative stress (8). Asthma is another inflammatory disease where nutrition may be able to play an ameliorating role. One study randomly assigned either a placebo or a nutrient supplement containing omega-3 fatty acids, vitamin C, and zinc to children with asthma and found a significant improvement in pulmonary function tests and inflammatory markers associated with the supplement (9). A clinical trial of healthy adults showed that consuming encapsulated fruit and vegetable juice powder concentrate for 60 days had a positive effect on various inflammatory biomarkers (10). Researchers found that consumption of tomato juice containing 21 mg lycopene for two weeks resulted in a significant reduction in C-reactive protein (11).
A study of zinc supplementation in healthy elderly subjects found that 45 mg zinc per day for six months decreased the concentration of serum C-reactive protein and various other inflammatory biomarkers (12). A study in obese prepubescent children found that supplementation with 20 mg zinc per day for eight weeks was associated with a significant decrease in markers of insulin resistance, oxidative stress, and inflammation (13).