Name: Dates (and other dried fruits)

What is it? Fruit that has been dried to remove water and so concentrates the sugars already present in the fruit. Fruits such as raisins, dates, prunes and apricots are dried in the sun or in heated wind tunnel dryers.

Many fruits such as cranberries, blueberries, mango and pineapple are infused with a sucrose syrup or apple juice and then heated or dried, which further increases their sugar content.

Found in? Available in most shops and supermarkets. The fruit retains much of its original flavour and is widely used by the confectionery, baking, and sweets industries. As ingredients, dried fruits and their juices, purées and pastes impart sweetness and texture and are also often used in home baking.

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The raw food trend has seen an increase in the number of products such as cereal bars that contain high proportions of dried fruits. For example, products in the Nakd range can contain 49% dates, and 17% raisins with nuts and flavourings.

Effect on general health Dried fruits are a good source of iron and fibre in the diet. The glycaemic index (GI) of traditional dried fruit is low to moderate (29-62) and the insulin response is proportional to their GI. However, as the sugar content of fruit (mainly fructose) is concentrated when the fruit is dried, they do contain, weight for weight, more sugar than fresh (64 g sugar per 100 g raisins). The key is portion size – a portion of dried fruit is around 30 g (one tablespoon of raisins, three dried apricots). It is, however, easy to overeat dried fruit and so the sugar and calories can add up.

Sulphur dioxide is used in some dried fruits, such as dried apricots, to protect their colour and flavour. Sulphur dioxide, while harmless to healthy individuals, can induce asthma when ingested by sensitive people.

Oral health impact Dried fruit contains large amounts of fermentable carbohydrate (mainly glucose and fructose) which is detrimental to oral health. The current recommendation from NHS England is to consume dried fruit with a meal and never as a snack due to its 'sticky' nature. This has been challenged in a review by Sadler1 which suggests that the evidence base is weak and there are positive attributes for dental health, such as the need to chew dried fruits which encourages salivary flow, and the presence of anti-microbial compounds. It must be noted that the review was funded by the California Prune Board.

Advice for patients A good product but should be eaten in moderation. While more work is establishing the extent of the effects of eating dried fruit on teeth, dried fruits and products containing them are best enjoyed as part of a meal, not as a between-meal snack. Oral hygiene needs to be maintained.

Find out more about the British Dietetic Association at: www.bda.uk.com.

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