Dutch food advisory board Voedingscentrum has withdrawn advice issued decades ago about not eating beetroot, spinach and lettuce more than twice a week.

The centre issued the recommendations because of fears about the health risks associated with eating too many nitrate-rich foods. However, research shows the risk is negligible and it is more important to promote the consumption of vegetables, spokesman Stephan Peters told the Volkskrant.

The centre has also withdrawn its advice not to combine nitrate-rich vegetables with fish.

However, the recommendation not to drink beetroot juice or concentrate every day remains, the centre said. Beet juice is used by some athletes as a sports supplement because they consider the nitrate content to be performance enhancing.

Nitrates can provide a variety of health benefits, but some nitrate is converted to nitrite when eaten. This in turn can then form nitrosamines which are thought be carcenogenic.