Eat a Rainbow for a Healthy Immune System

Health experts explain why it's important to consume a variety of colourful fruits and veggies for maximum health

Incorporate a variety of colourful fruits and veggies into your diet for maximum health

We often hear that eating a diverse and colourful diet is best for promoting good health and building a strong immune system. Due to their alkaline-forming properties, brightly coloured fruits and vegetables can minimize internal inflammation, which can lead to chronic disease.

Licensed naturopathic physician Dr. Jason Marr suggests eating a variety of colourful produce everyday since all phytonutrients (plant nutrients), especially those which are antioxidants, work best to promote good health when eaten in combination. A good rule to abide by is to try and eat 2 to 3 different colours of foods to ensure consuming a good variety of phytonutrients.

According to naturopathic physician and holistic nutritionist Michelle Book, eating vegetables with distinctive colours do contribute to a healthier immune system. A useful tip to keep in mind is that the deeper the colour, the more concentrated the phytonutrients.

Click through for what Book and Marr consider the healthiest food choices based on colour.


A helpful phytonutrient in green fruits and vegetables is lutein. Lutein can be found in spinach, kale, other dark leafy greens, avocados, kiwis, green peppers, cucumber and celery. Lutein is a great antioxidant known to keep eyes healthy. Lutein works well with zeaxanthin, a chemical found in oranges, red peppers, grapes and egg yokes. Green cruciferous vegetables such as broccoli, cabbage, and Brussels sprouts are also beneficial in preventing cancers. Others to consider are green beans, artichokes, sprouts and collards.


Fruits high in phytonutrients include Golden Delicious apples, grapes, plums, lemons, pears, mangos, bananas, pineapple, and starfruit. Yellow vegetables to include are corn, bell peppers, onions, and potatoes.

Orange and Purple


One of the healthiest fruits are oranges as they are an excellent source of Vitamin C and folate. Also, peaches, nectarines, apricots, and papayas are rich in phytonutrients. Good choices of orange veggies are of course carrots, yams, and pumpkins, all containing beta carotene which is converted to Vitamin A when digested and helps maintain healthy eyes and your immune system.


Blue & Purple

Anthocyanins are a class of nutrient that gives us blue-purple foods such as blueberries, blackberries, grapes, plums, boysenberries, purple cabbage, olives, and eggplant. High in phytonutrients, they are effective antioxidants that protect cells from free radical damage, boost the immune system and limit risk for urinary tract infections.


Red foods contain lycopene, which is known for its anti-cancer effects and is a great antioxidant. Some of the best choices are cherries, plums, grapefruit, pomegranate, watermelon, all of the berries, apples, tomatoes, and bell peppers.