Intakes, Adequacy, and Biomarker Status of Iron, Folate, and Vitamin B ₁₂ in Māori and Non-Māori Octogenarians: Life and Living in Advanced Age: A Cohort Study in New Zealand (LiLACS NZ)

Abstract

Advanced-age adults may be at risk of iron, folate, and vitamin B ₁₂ deficiency due to low food intake and poor absorption. This study aimed to investigate the intake and adequacy of iron, folate, and vitamin B ₁₂ and their relationship with respective biomarker status. Face-to-face interviews with 216 Māori and 362 non-Māori included a detailed dietary assessment using 2 × 24-h multiple pass recalls. Serum ferritin, serum iron, total iron binding capacity, transferrin saturation, red blood cell folate, serum folate, serum vitamin B ₁₂ and hemoglobin were available at baseline. Regression techniques were used to estimate the association between dietary intake and biomarkers. The Estimated Average Requirement (EAR) was met by most participants (>88%) for dietary iron and vitamin B ₁₂ (>74%) but less than half (>42%) for folate. Increased dietary folate intake was associated with increased red blood cell (RBC) folate for Māori ( p = 0.001), non-Māori ( p = 0.014) and serum folate for Māori ( p < 0.001). Folate intake >215 µg/day was associated with reduced risk of deficiency in RBC folate for Māori ( p = 0.001). Strategies are needed to optimize the intake and bioavailability of foods rich in folate. There were no significant associations between dietary iron and vitamin B ₁₂ intake and their respective biomarkers, serum iron and serum vitamin B ₁₂.