The Rainbow Diet: How Important Is The Colour Of Food?

Posted on January 16, 2018 by Guest Writer

Food is the oldest form of medicine, and in the East, the colour of the food is often used as a guide in helping patients to plan a diet to help heal various ailments in the body. Even here in the UK, many nutritionists are now suggesting we eat a rainbow of different fruit and veg so as to get a diet packed with goodness across the spectrum – literally.

But what is it about the natural colour of food that’s so important? Well, the clue lies in the science behind what makes the colour in the first place. When it comes to fruit and veg, it’s their colour that tells us which nutrients they hold.



Red foods contain antioxidants including lycopene, anthocyanins, ellagic acid and astaxanthin. Lycopene gives red fruits their colour and is actually more easily absorbed in the body when cooked. So homemade tomato sauce is definitely a good place to start.



Orange foods are high in carotenoids, such as alpha and beta-carotene. It’s the beta-carotene that gives orange and yellow fruits and vegetables their colour and is converted to vitamin A in the body. This is good for making hormones and keeping eyes healthy, hence the saying that carrots make you see in the dark. Citrus fruits like oranges are lower in vitamin A but super high in vitamin C.

Halved and whole papaya fruits on the background


Yellow foods also contain carotenoids. Whilst their colour comes from beta-carotene, foods such as sweetcorn, papaya, egg yolk and peach are rich in the antioxidant beta-cryptoxanthin. This can also be converted into vitamin A

Various leafy vegetables


As is the case with the leaves on all green plants and trees, green foods get their colour from chlorophyll. However, they are also packed with other goodness such as sulforaphane and glucosinolate – the former of which has shown promise in protecting against blood-vessel damage and certain cancers. Though more research is still needed.

Red Beetroot with green leaves


Foods that are blue and purple get their colour from anthocyanins, which are powerful antioxidants. Purple beetroot (along with many other vegetables) is also rich in nitrates, which may help to reduce blood pressure and the risk of cardiovascular disease.



Anthoxanthins are the pigments that makes foods white and cream in colour and have been suggested to aid with inflammatory conditions such as arthritis. Though as is the case with all food studies, more research is needed.

White potatoes however, may get a bad rep but are actually packed with vitamin C and potassium, and the skin is a good source of fibre. Bananas, mushrooms and parsnips are also high in potassium which is important for healthy heart and muscle function.

So there we have it: how foods get their colour. It is important to note that whilst all fruit and veg is extremely good for us, their specific medicinal qualities have yet to be proven to a level that enables us to speak it as hard truth.

The best bet is to eat a balanced and varied diet, which really is a rainbow diet anyway. Plus it looks and tastes great.