Effects of Flavonoid Foods on Carbonyl Stress

This randomized crossover study will compare low- and high-flavonoid diets in healthy adults to identify flavonoid-derived biomarkers in urine and plasma. Using targeted liquid chromatography-mass spectrometry (LC-MS) metabolomics, researchers will measure known and novel flavonoid metabolites and evaluate whether a higher flavonoid intake reduces carbonyl stress markers, including reactive carbonyl species (RCS) and advanced glycation end products (AGEs).

Inclusion Criteria: * Age 25-70 years * BMI between 18 and 30 * Have no known allergy to test food * Have no known allergies to green tea, apples, blueberries, soy milk, or pineapples * Be not engaging in high-intensity exercise * Having blood and urine clinical tests in the normal range. * Be not taking antibiotics for six months * Be not currently taking medication * No taking any prescription drugs * All flavonoid-enriched supplements should be avoided. The flavonoid-enriched supplements list includes soy isoflavones, Lipo-Flavonoid, Citrus Bioflavonoids Complex, Super Flavonoids, Super Antioxidants, Quercetin Supplement, Essential-C, flavonoids, and milk thistle. Also other flavonoid supplements, including but not limited to luteolin, Rutin, etc. * No drugs or supplements within three weeks of the experiment * Be nonsmoking * Have no alcoholic intoxication * No alcoholic addiction * \< 3-4 drinks per week (less than 2 glasses (300 mL) per drink) * No alcohol within three weeks of the experiment * Have no extended exposure to industrial wastes Exclusion Criteria: * Disease: gout, heart disease, peripheral vascular disease, degenerative kidney, degenerative liver, diabetes, GI disorders, or endocrine disorders * Cancer patients * Currently diagnosed cancer patients will be excluded. * Medication-free for \>2 years could be considered.