The Food Hospital, a weekly television programme on Britain’s Channel 4 has conducted an experiment to find if blueberries enhance brain function.

Volunteers were workers in a small advertising sales business who need to stay alert all day to maximise sales. The doctors provided one smoothie to each worker at 10am every working day for two weeks.

During the first week they were given a banana drink, the second week a handful of blueberries in a smoothie.

The results were decisive. During the banana week, the team showed a small improvement in function in the mornings, but a significant drop off in the afternoons.

In the blueberry week, there was a marked improvement in the mornings and, contrary to the banana results, a continued superiority in the afternoons.

There is no question that the blue antioxidant, anthocyanin, in the blueberries did improve both brain efficiency and longevity of functioning.