Lynne Hill, of Mosgiel, asks :-
Recently, the recommendation of five plus a day of fruit and vegetables has changed to only two servings of fruit, the rest of vegetables. Given that some vegetables are actually classed as fruits, e.g. tomatoes, does your tomato count as fruit or vegetable, are all berries fruit, or do dieticians have different definitions for fruit and vegetables?
Elizabeth Aitken, the Principal Nutrition Advisor at the Ministry of Health, responded.
For many years now the Ministry of Health has recommended adults to eat at least five servings of vegetables and fruits each day. This advice has always been based on at least three servings of vegetables and two servings of fruits daily. The number of servings varies across age groups.
The Ministry uses a practical approach (rather than referring to botanical origins) for including products in the vegetable or fruit groups, so in New Zealand tomatoes are in the vegetable group and all berries are in the fruit group. The Ministry would expect that dietitians in New Zealand are using the 2015 Eating and Activity Guidelines for New Zealand Adults (download from www.health.govt.nz under publication then eating-and-activity-guidelines) as the basis for healthy eating advice for most people. There is further guidance on what a serving size of vegetables and fruits is for New Zealand in the accompanying resources for consumers.
We are aware that other countries define a vegetable or a fruit differently to what we do (eg potatoes are in the vegetable group in New Zealand but not in some other countries) and they may also include a different definition of what a serving size is and how many servings are recommended per day.
You mention the 'five plus a day' recommendation, which is an industry sponsored programme run by United Fresh in New Zealand that uses the size of the hand for the serving size. While this is a slightly different way of promoting vegetable and fruit consumption, the message is positive and similar to the Ministry's recommendation.
The important message is that New Zealanders should eat plenty of vegetables and fruits (recent survey data found that for adult New Zealanders 63 percent ate at least three servings of vegetables and 56 percent ate at least two servings of fruit daily) as they are good for staying healthy including maintaining a healthy body weight. Vegetables and fruits have important plant chemicals which help protect the body from some of the major diseases, such as heart disease, stroke and some cancers.
Send questions to: Ask-A-Scientist, PO Box 31-035, Christchurch 8444 Or email: firstname.lastname@example.org