Antioxidant intake relative to established dietary recommendations and cognitive status in older adults

BACKGROUND: Oxidative stress, the imbalance of prooxidants and antioxidants, has been recognized as a contributor in the development of age-related cognitive decline and Alzheimer's disease and Alzheimer's disease related dementias (AD/ADRD). Exogenous antioxidant intake may play a role in maintaining cognitive health during aging; however, few studies have examined cognitive status in relation to established antioxidant intake recommendations in older adults. OBJECTIVE: This cross-sectional study investigated cognitive status differences among older adults based on adequacy of dietary antioxidant intake. METHODS: Participants (n = 50, 71.5 ± 5.1 years old, 66% female) completed three-day food logs. Recommended Daily Allowance (RDA) defined antioxidant adequacy for vitamin C, vitamin E, selenium (Se), while Adequate Intake determined antioxidant adequacy for manganese (Mn). The Saint Louis University Mental Status (SLUMS) examination categorized normal cognition, mild neurocognitive disorder, or dementia via 30-point scale. RESULTS: No significant differences in mean SLUMS scores were observed between participants with adequate versus inadequate antioxidant intake; however, there were significant differences in cognitive status distribution by adequacy of vitamin C (p = 0.001), vitamin E (p = 0.024), Se (p = 0.018), Mn (p = 0.001), and all four combined (p = 0.002). A higher proportion of participants with inadequate intake had cognitive impairment. CONCLUSIONS: Antioxidant adequacy may be associated with clinically meaningful cognitive classification thresholds.