Plasma carotenoids and (poly)phenols in people living with an ileostomy: associations with dietary intake

Individuals with an ileostomy (ileostomists) face unique physiological and dietary challenges that may impact on the bioavailability of phytochemicals, including carotenoids and (poly)phenols. In this study, we aimed to investigate habitual intake of phytochemical-rich foods and circulating concentrations of lutein, zeaxanthin, and phenolic compounds in ileostomists. In a cohort of 57 adults with an ileostomy (mean age 52.1 ± 15.0 years), habitual intake of phytochemical-rich foods and circulating concentrations of key carotenoids and phenolic compounds were markedly low. Mean intakes of fruit and vegetables (181.8 g day ⁻¹), lutein (0.3 mg day ⁻¹) and total (poly)phenols (524.4 mg day ⁻¹) were substantially below population averages, which was reflected in low plasma concentrations of lutein (0.14 ± 0.11 µM), zeaxanthin (0.04 ± 0.04 µM) and phenolic metabolites (0.34 ± 0.15 µM). Associations between dietary intake and circulating biomarkers were generally weak, although lutein intake was moderately correlated with plasma lutein (r = 0.52, P < 0.001). Circulating phytochemicals remained consistently low irrespective of time since surgery, highlighting the combined effects of dietary restriction and loss of colonic metabolism. These findings underscore the need to explore dietary reintroduction strategies and targeted supplementation to support long-term health in ileostomists.