Can eating fruit make vaccines work better?

Eating five portions of fruit or vegetables a day could make vaccines against some infectious diseases more effective, according to a new study.

Researchers from Queen’s University Belfast tested 80 volunteers between the ages of 65 and 85 in two groups. One stuck to its normal intake (around two pieces of fruit or vegetables a day) for 16 weeks, while the rest increased their intake to five pieces a day. The volunteers were then vaccinated against tetanus and pneumococcal infection.

The volunteers had their blood tested to measure their immune system response. The results, published in the European Journal of Clinical Nutrition, showed the greatest immune response was seen in reaction to the pneumococcal jab in the five-a-day group.

Eating more fruit and veges did not appear to have a significant effect on the tetanus jab. Larger trials are planned to find out why.