Cereals are often recommended for heart health as many have high levels of dietary fibre. But a team from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston and Michigan State University report that just one cup of fortified breakfast cereal daily significantly increased B vitamin levels and decreased homocysteine concentrations in a group of volunteers.
High homocysteine and low B vitamin concentrations have been linked to the risk of vascular disease, stroke, and dementia and are relatively common in older adults.
A study carried out over 14 years by researchers in Illinois, US, found that men with the highest intake of folic acid were almost 30 per cent less likely to develop an ischaemic stroke than men with the lowest folic acid intake (less than 260 micrograms). Ischaemic stroke accounts for almost 80 per cent of all strokes and is caused by a blocked artery leading to the brain.
The new study involved 189 volunteers aged 50-85 years old. All subjects were free of hypertension, anaemia, asthma, cancer, or cardiovascular or digestive disease and did not regularly consume multiple or B vitamin supplements or highly fortified breakfast cereal.
Subjects were randomly assigned to consume one cup of breakfast cereal fortified with 440 micrograms folic acid, 1.8 mg vitamin B-6, and 4.8 micrograms of vitamin B-12 or placebo cereal for 12 weeks. Blood was drawn at baseline and again after two, 12, and 14 weeks. Methionine-loading tests were also carried out to measure homocysteine breakdown.
Final baseline-adjusted plasma homocysteine concentrations were significantly lower and B vitamin concentrations were significantly higher in the treatment group than in the placebo group, write the researchers in this month's American Journal of Clinical Nutrition (vol 79, no 5, 805-811).
The percentage of subjects with plasma folate concentrations less than 11 nmol/L decreased from 2 per cent to 0 per cent, while those with vitamin B12 concentrations less than 185 pmol/L fell from 9 per cent to 3 per cent. Those with low B6 levels also decreased from 6 to 2 per cent.
Meanwhile homocysteine concentrations above 10.4 µmol/L in women or 11.4 µmol/L in men fell from 6.4 per cent to 1.6 per cent, they reported.
The role played by B vitamins, homocysteine and heart disease risk still needs to be confirmed however. In the earlier cited Illinois study, there was no significant assocation between B vitamins and haemorrhagic stroke, caused in a different way to ischaemic stroke.