Intakes of folate and vitamin B12 from total diets and from specific food groups and biomarkers of status in the very old

Very old adults are at increased risk of folate and vitamin B12 deficiencies due to reduced food intake and gastrointestinal absorption. This study aimed to determine whether higher intakes of folate and vitamin B12 from total diets and top contributing food groups were associated with reduced risk of inadequate vitamin status among 85 year-olds from the Newcastle 85+ Study. Two 24hr multiple pass recalls were conducted by a research nurse at the participants’ usual residence and dietary intake estimated with the McCance and Widdowson’s 6 edition food composition tables. Red blood cell folate (RBC folate) and plasma B12 were analysed by chemiluminescent immunoassays. Complete dietary intake data and B-vitamin biomarkers were available for 732 participants. Binary logistic models were used to estimate the risk of inadequate RBC folate (only 3·4 % of individuals were <340 nmol/L, therefore a threshold of <600 nmol/L, was used) and plasma B12 (<148 pmol/L) concentrations according to quartiles of folate and vitamin B12 intake from total diets and from specific food groups.