Are Colourful Vegetables Healthier?

2 June 2016, written by Benedict Vanheems

As a child you were probably encouraged to eat your greens. But what about your blues, reds, purples and yellows? Can eating a rainbow of fruits and vegetables really improve your general wellbeing? The short answer is a resounding, double-thumbs-up ‘yes’!

Eating produce in a rainbow of colours is a straightforward, no-nonsense alternative to navigating the ever-moving landscape of the ‘superfood’. Previously, fellow blogger Ann Marie argued that the whole concept of so-called ‘superfoods’ was little more than marketing spin. The health benefits of these foods are often exaggerated, caught up in a sort of nutritional one-upmanship that ultimately creates a fog of confusion; it’s hard to know what to believe and how far to trust the sometimes fantastic claims made.

Rainbow Fruits and Vegetables

The truth is that all fruits and vegetables are super foods in their own way. It’s also fair to state that fruits and vegetables of different colours offer different nutritional advantages. So a purple carrot offers a different set of health benefits to a traditional orange carrot. Blueberries – the go-to ‘superfood’ – are of course good for us, but so too are redcurrants, blackberries and greengages. They all bring something unique to the table.

Let’s explore the aforementioned carrot as an example. You may (or may not) be surprised to learn that carrots come in a range of colours, the result of their origin or breeding. All of them are good for us, but for a variety of reasons. Purple carrots have higher levels of anthocyanins, which contribute to heart health, while red carrots are rich in lycopene, a pigment known to safeguard eye health. Yellow carrots on the other hand contain high concentrations of lutene, a pigment shown to slow hardening of the arteries.

So in this example we can use a single crop to demonstrate how each of the plant pigments responsible for particular colours will give different health benefits. In the spirit of scientific method the carrot acts as our scientific control, while the pigments serve as our variable. The conclusion to be drawn from this is that there’s something in the claim that eating a rainbow of produce is good for us.

Eat the Rainbow

Now let’s investigate the most common plant pigments a little further and find out which fruits and vegetables have them in the highest concentrations.

Lycopene: This powerful antioxidant gives many fruits and vegetables their red colour. As well as contributing to eye health, lycopene is believed to reduce the risk of cancer and heart disease. High amounts of it can be found in fruits such as guavas, watermelons and papayas. Red tomatoes have loads of it too.

Anthocyanin: Responsible for the blue-purple of a multitude of crops, including blueberries. Foods rich in anthocyanin can help to mop up cell-damaging free radicals and generally slow the ageing process. Common anthocyanin-laden produce includes blackberries, plums, cherries and cranberries, plus eggplants, red cabbage and purple varieties of cauliflower and potato.

Lutene: It has been suggested that lutene and another carotenoid called zeaxanthin, like lycopene, can decrease the risk of macular (eye) degeneration. Lutene is associated with yellow or pale green fruits and vegetables. A scientific study found that maize (corn) has among the highest quantities of lutene, while orange peppers are particularly rich in zeaxanthin. Other foods to grow for their lutene intensity include kiwi fruit, spinach, squashes and zucchini.

Beta-carotene: The pigment behind orange vegetables is also present in many other vegetables. Top of the list is the sweet potato, closely followed by carrots. Spinach, kale and just about any other leafy greens are chock full of beta-carotene, while squashes, pumpkins, green peppers and lettuce also score highly.

Heirloom Varieties

While there’s undoubtedly a cornucopia of crop colours to be had from many common varieties of fruits and vegetables, there is a veritable universe of choice in rarer heirloom or heritage varieties. Many of these traditional varieties bring a wealth of shapes, textures, sizes – and colours. Take, for example, the tomato. Joining red and yellow fruits are black, white, green, orange – and everything in-between. Other crops that are available in a rainbow of colours include chard, peppers, radishes, beetroot/beet and, of course, carrots.

So if you want a no-thought way to improve your nutritional health, simply aim for a good mix of colours in your planting plan and in your diet. It’s not exactly rocket science, but then it’s the simplest concepts that bear the test of time.