The rainbow diet: Health benefits of coloured fruits and vegetables

From white, the brightest orange, to the deepest purple — make your meals and snacks as colourful as possible. Each colour provides unique health benefits and no one colour is superior to another, which is why a balance of all colours is most important. The ultimate goal of a 'rainbow diet' is to add 30 plus different colourful fruits and vegetables to your meals every week. Just plan for one colourful plant-based food at every meal and instead of rich, sugary treats after the meals or for between-meal snacks, use fresh fruits to satisfy the sweet tooth.

Read on to learn more about the health benefits of coloured fruits and vegetables.

Food coloured red like tomatoes, watermelons, red peppers, strawberries, pomegranate seeds, apples, red current cranberries, red onions, radishes, red beans, beets, strawberries, and raspberries are all packed with vitamin C, vitamin A, potassium, lycopene, etc.

They are rich in antioxidants and anti-inflammatory molecules that prevent inflammation and oxidative stress. The phytochemicals present may help protect against certain cancers (especially prostate cancer), lower the risk of diabetes, support eye health, and improve skin appearance.

Photo: Sazzad Ibne Sayed

Orange- and yellow-coloured foods are rich in Vitamin C and carotenoids, including beta-carotene. They have phytonutrients like red-coloured food that promote healthy vision and cell growth.

Citrus fruits contain hesperidin which increases blood flow and can potentially help prevent strokes. Orange fruits and vegetables also support the reproductive health of men and women.

Yellow foods are particularly good for the digestive tract. They contain prebiotics that encourage our gut bacteria to produce short-chain fatty acids — special molecules that nourish the cells of our gut.

Healthy orange and yellow food include pumpkins, sweet potatoes and carrots, sweet corn, yellow and orange peppers, orange lentils, citrus fruits like lemons, oranges, and grapefruit; pineapples, corns, starfruits, papayas, mangoes, turmeric, yams, peaches, and apricots.

Greens mean a lot of heart-protective potassium and vitamin K, which aid the blood clotting process and lower hypertension, maintain vision health, and strong bones and teeth.

Dark green, leafy vegetables have the highest concentration of antioxidants, fibres, and folates — a nutrient that is important to pregnant women.

Kale has as much calcium as milk, supports digestive enzymes, and aids in the absorption of nutrients boosting the immune system, increasing energy, and faster healing of tissues. These food are rich in cancer-blocking chemicals that inhibit the action of carcinogens — found in abundance in spinach, avocados, okras, broccoli, peas, kale, cabbages, Brussels sprouts, kiwi fruits, grapes, bell peppers, collard greens, green tea, green apples, lime, olives, pears, and green herbs like mint, rosemary, thyme, and basil.

Fruits and vegetables that are blue and purple like eggplants, purple cabbages, beetroots, radishes, purple carrots, black olives, berries (blueberries and blackberries), passion fruits, purple grapes, purple plums, prunes, raisins, and dark cherries are rich in anthocyanins and proanthocyanidins antioxidants. They are amazing for memory, cellular strength, reducing inflammation all over the body, and preventing cellular damage. They also boost the health of the urinary tract and promote healthy ageing.

Fruits and vegetables coloured white support bone health, help to lower cholesterol and reduce inflammation, protect against certain cancers, and balance hormones.

Cauliflower is a cruciferous vegetable rich in a healthy compound called sulforaphane.

Garlic and onions are in the allium family of vegetables and contain the powerful compounds allicin and quercetin that help to reduce the risks of cancer and have anti-inflammatory properties.

Selenium – found in mushrooms – plays a key role in supporting the immune system.

Super white foods to eat include cauliflowers, garlic, shallots and onions, leeks, parsnips, white beans, bananas, and lychees.

Chowdhury Tasneem Hasin 
Chief Clinical Dietician & HOD
Clinical Dietetics and Nutrition Dept,
United Hospital ltd.
AGS, BNDF