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Life Sciences => Physiology & Medicine => Topic started by: phatboy on 14/01/2010 14:52:03

Title: Why does juice only count as one of my five-a-day?
Post by: phatboy on 14/01/2010 14:52:03
I've been trying to find out what fruit juice only counts as one of my five-a-day and smoothies as two, but I cannot find an answer anywhere on the internet.

Does anyone know?
Title: Why does juice only count as one of my five-a-day?
Post by: Don_1 on 14/01/2010 15:24:26
It will depend on how many different juices/smoothies you drink. It takes around 15 oranges to produce 1 ltr of juice. But it must be fresh juice, not the 'made from concentrate' juice. 150mls counts as one of your five a day, but 300mls does not count for two.

Quote from: NHS

Juices and smoothies

One 150ml glass of unsweetened 100% fruit or vegetable juice can count as a portion. But only one glass counts, further glasses of juice don’t count toward your total 5 A DAY portions.

One smoothie containing all the edible pulped fruit or vegetable may count as more than one 5 A DAY portion, but this depends on the quantity of fruits or vegetables and/or juice used, as well as how the smoothie has been made.

For a single smoothie to qualify as being two portions, it must contain either:

•at least 80g of one variety of whole fruit and/or vegetable and at least 150ml of a different variety of 100% fruit and/or vegetable juice, or
•at least 80g of one variety of whole fruit and/or vegetable and at least 80g of another variety of whole fruit and/or vegetable.
Smoothies count as a maximum of two of your 5 A DAY, however much you drink.

Sugars are released from fruit when it's juiced or blended, and these sugars can cause damage to teeth. Whole fruits are less likely to cause tooth decay because the sugars are contained within the structure of the fruit.

Find more here (http://www.nhs.uk/Livewell/5ADAY/Pages/Portionsizes.aspx).
Title: Why does juice only count as one of my five-a-day?
Post by: glovesforfoxes on 15/01/2010 12:05:50
I can't think of a physiological reason why you couldn't get all of your 5 a day from smoothies, as long as you drank the smoothies over the course of the day to prevent blood sugar spikes. I think the NHS tells you that so that you don't drink too much at once & get sick or so that you don't have blood sugar spikes. However, what they say about sugars on teeth seems valid, so it'd damage your teeth more. Course, if you brushed your teeth afterwards you'd be okay, but so much effort to liquefy foods! I add kale or spinach (baby spinach is even better, you can add more without it tasting different) to my smoothies sometimes to boost it's nutritional value; it's taste is covered up by the fruit.
Title: Why does juice only count as one of my five-a-day?
Post by: phatboy on 17/01/2010 23:13:43
Thanks for that... just realised there is a typo in my original question but glad you worked out what I meant.
Title: Why does juice only count as one of my five-a-day?
Post by: Bored chemist on 18/01/2010 19:49:18
One possible reason that fruit juice only counts as one is that it doesn't provide the fibre that fruit (or a smoothie) would.