Updated: Jul 2
I mentioned on the podcast that among the six areas of focus in lifestyle medicine, nutrition is the first step towards lifestyle change. I have written an article about nutrition, particularly a whole-food, plant-based diet. In that article, I mentioned how to start and eat the colors of the rainbow.
In this article, I will discuss the food items that represent the colors of the rainbow and its benefits. This way, you will have an idea on your food choices and would be most likely to choose functional foods. Functional foods are dietary components that provide health benefits beyond basic nutrients.
We have been taught since we were kids to eat fruits and vegetables because these foods contain not only vitamins and minerals but also phytonutrients. Phytonutrients are bioactive plant-derived compounds associated with positive health effects. Phytonutrients are pleiotropic, meaning they do have multiple effects on our cells’ structure and function. And because of this, phytonutrients are helpful in preventing chronic diseases.
Not only that, anti-inflammatory plant compounds like polyphenols and other phytochemicals help offset toxicity from pollutants.
Also, a study among 12,285 Australian adults showed an increased intake of fruits and vegetables had a favorable impact on their psychological well-being. Another study in New Zealand showed that those who ate more fruits and vegetables for more than thirteen consecutive days flourished in their daily lives with high levels of well-being, intense feelings of curiosity and creativity compared with adults who ate less fruits and vegetables.
And there are numerous studies that showed intake of fruits and vegetables is associated with reducing chronic disease risk. One of them is a study which introduced the term “phytochemical index” in 2004. Phytochemical index is the percent of dietary calories from foods rich in phytochemicals. A high phytochemical index shows favorable effects on preventing weight gain, along with improved lipid levels, and lowered risk of hypertension and breast cancer.
Low Phytonutrient Intake
However, even though we know that eating fruits and vegetables is a part of a healthy diet, people continue to have a low intake of these nutrients below the recommended dietary allowance called “phytonutrient gap”.
To visualize this phytonutrient gap, a study showed that eight out of ten Americans fall short of the recommended daily allowance for each color of phytonutrients especially the purple/blue foods. Another study showed that only nine percent of American adults met the recommended daily allowance for vegetables and only twelve percent met the recommended daily allowance for fruits.
The “Eat by Color” Approach to Increase Fruit and Vegetable Intake
Although eating recommended quantities of fruits and vegetables continues to be a challenge among most people, it is much easier to adopt a qualitative color approach rather than a quantitative serving approach.
The concept of eating by colors of the rainbow seems to be an effective strategy for people in improving their diet. It can also be implemented across all ages.
For easy reference and memory, each color is associated with some general related health benefits. Each color corresponds to foods, phytonutrient content, and beneﬁts which were determined based on research publications.
Red Foods and Inflammation
Red foods are high in phytonutrients such as astaxanthin, lycopene, ascorbic acid (vitamin C), fisetin, and other classes of anthocyanins which exhibit anti-inflammatory properties and immune-modulating activities. Examples of red foods are cherries, tomatoes, red bell pepper, watermelon, grapefruit, apples, pomegranate, strawberries, cranberries, and raspberries.