Extra zinc taken during pregnancy leads to bigger, healthier babies, according to US researchers writing in the Journal of the American Medical Association. In a study at the University of Alabama involving nearly 600 pregnant women, they found those who were given daily zinc supplements delivered heavier babies who suffered fewer infections.

Zinc is found in seafood, nuts and milk. In the UK the recommended daily allowance for pregnant women is 20mg, while the US researchers used doses of 25mg daily.