It’s official! Older people only need to be mildly deficient in vitamin B12, to be likely to experience cognitive decline, so says Martha Savaria Morris, Ph.D., an epidemiologist in the Nutrition Epidemiology Program at the HNRCA at Tufts University, Boston, USA.

One in 10 people over the age of 70 have a severe B12 deficiency and pernicious anaemia affects one in 10 000, but even a slight decline, will render you less brainy.

So if you want to ‘up’ your vitamin B12 intake – meat, poultry and eggs, also broccoli, Brussel spouts and peas, will help you do the job. It is recommended, however that people over 50 may not find it easy to absorb enough B12 from food, and might want to consider taking a supplement. Check with your pharmacist for an appropriate dosage.