The aim of this study is to determine the best source of folate to raise the folate status of a general population over a 16 week intervention period.

This study is designed to assess whether increasing the consumption of natural food folates from a mixed diet is as effective as supplemental folic acid or supplemental natural folate in raising folate status, reducing biomarkers of cardio vascular disease (CVD) risk, and improving vascular function. Randomised placebo-controlled parallel studies will be undertaken in groups of individuals in Norwich and Sheffield. There will be four treatment arms: a) 200 µg folate per day from folate-rich foods, b) 200 µg folate per day from supplemental folic acid, c) 200 µg folate per day from supplemental Metafolin® (6S 5-methyltetrahydrofolic acid) and d) a placebo group. Results from the two centres will be combined, thus ensuring a wide population is covered. Folate status, biomarkers of CVD risk and vascular function (pulse wave velocity) will be measured before and following the intervention period of 16 weeks, together with possible confounders (such as vitamins B2 & B12 status, and MTHFR genotype). 7-Day weighed intakes will be used to measure habitual B-vitamin intake during baseline and intervention, to determine changes in folate intake and assist compliance. Additionally, folate content of selected folate-rich foods will be determined for each volunteer. The results will aid the Food Standards Agency (FSA) in formulating public health policy related to improving folate status and reducing CVD risk.

Inclusion Criteria:

• Men and women aged 18-65 years
• Smokers and non-smokers

Exclusion Criteria:

• Pregnant or has been pregnant within the last 12 months
• Breastfeeding
• Has donated or intends to donate blood within 16 weeks of the first or last study samples
• Fails standard clinical screening of blood and urine for human studies at the Institute of Food Reseach
• BMI above 18 or below 40
• Receiving vascular disease or anti-hypertensive drugs
• Those with diabetes
• Regularly consuming dietary supplements containing B-vitamins and/or folic acid.

[As the capsules are prepared from gelatin, true vegetarians may not wish to participate]