Food Basics: Vegetables and the Color Principle


My guess is that most readers of this blog have rarely gone a day without eating at least one vegetable. We know veggies are the mainstay of a healthy eating plan and the dietary linchpin for fending off cancer and many other diseases.

Nutritionists are fond of saying that vegetables are nutrient-dense, low-calorie fare because, on a per-calorie basis, they pack quite a nutritional wallop. Fresh, organically grown vegetables, wild edible plants (e.g.,  stinging nettle, dandelion, lambsquarters), and seaweeds are the most nutrient-dense of all.

But in these days of large-scale monoculture farming, vegetables can also be depleted in nutrients due to storage, shipping, and processing. For instance, spinach, lettuce and other greens suffer more than a 30 percent loss of vitamin C due to temperature changes, air movement and humidity. Vitamins A, E and C are especially vulnerable to oxidation during storage; the loss of vitamin E due to this oxidation process may be 50 percent or more. Freezing and thawing can take a toll as well, especially if the freezing took place before the vegetables reached full maturity.

Another piece of advice you’ll hear about veggies is to get plenty of variety.  One of the practical ways to do this is to choose various colors of vegetables.  Different colors also tend to translate into different types and proportions of phytonutrients (plant-derived nutrients).  In general, the deeper and/or darker the color of the vegetable, the better its nutritional value.  Vegetables that are pale or clearly losing their color have also lost a fairly good portion of their nutritional value.

Pale, small carrots, for example, have several times less vitamin A than mature, bright-orange carrots. Ditto for tomatoes and their lycopene content.  Dark-green leafy vegetables are, for the most part, a great deal higher in nutrients than light greens, such as iceberg lettuce. Deep-orange vegetables like carrots or winter squash are loaded with carotenoids that get converted to vitamin A and have wonderful anti-cancer properties in their own right.

One last point about color is how you prepare your veggies.  You can eat vegetables in many ways—raw, steamed, baked, roasted, grilled, sautéed or stir-fried.  Though raw veggies are already quite colorful, cooking, too, can help bring out certain colors while also making certain phytonutrients more available to the body.  Of course, overcooking has the opposite effect—depleting nutrients and dimming colors simultaneously.

Though the color principle doesn’t guarantee an optimal diet, it can at least point you in a healthier direction. The mix of vegetable colors also serves as a kind of positive reinforcement, since it makes your meal a feast for the eyes as well as the belly. Adding color to your daily eating plan is just one additional way to ensure that you’re eating well and getting the most out of the plant world we know and love.

If you have questions or would like to schedule a health coaching session, please reach out.

© 2017, Mark Nathaniel Mead