5 a day - myth or truth?

The 'rule' about eating five portions of fruit and vegetables per day was invented in 1991 by the American National Cancer Institute and a group of Californian fruit and vegetable growers. It was adopted by the UK Department of Health in 2003. Because we at Qryztal are wary of convenient numbers, we decided to look into it a bit further.

Five portions of fruit and vegetables will give you the water soluble vitamins. If you base your five portions solely on fruit, you'll also be eating (or drinking) quite a lot of sugar (up to 74 grams) - because fruits are rich in fructose. Note that this is just the water soluble vitamins, not the fat soluble vitamins. You could, for example, gorge yourself on fruit and yet be walking around with a vitamin D deficiency - because vitamin D is fat soluble.

There is an argument that we should instead be thinking of superfoods instead of fruit and vegetables. For instance, liver contains a higher level of vitamins and minerals than anything else we came across in our research for this blog post. If instead of five fruit and veg you think of five superfoods, the list we came across is as follows:

• Liver
• Oily fish
• Eggs or dairy produce
• Sunflower seeds (for vitamin E)
• A leafy green vegetable

If you want seven a day, you could add these:

• Steak (for zinc)
• Cocoa powder (or dark chocolate) for minerals

It's starting to sound like the typical British diet in World War 2:

• Offal
• Sardines
• Eggs
• Cheese
• Green vegetables (plus potatoes)
• Red meat (in small quantities)
• Chocolate (when available - on the sweet ration)

...which would explain why, anecdotally, people were healthier during the period of food rationing than they have been since.

But... should you take vitamin and mineral supplements as a safety net? That's another subject, for another time.