Blue, Purple, and Black Fruits, Vegetables, and Legumes: A Deeper Dive Into the Rainbow
In The Rainbow Explained, I provided a quick overview of the nutritional benefits of different colored fruits, vegetables, and legumes. Now it’s time to dig a little deeper into each color of the natural food rainbow!
In this article, I’ll focus on the incredible powers of blue, purple, and black fruits, vegetables, and legumes. These colors may be harder to find than others in the food spectrum, but they are definitely worth seeking out! They have tremendous nutritional benefits.
Let’s dive into the treasure trove of healing, nourishing, and detoxifying nutrients that exist in blue, purple, and black plant-based foods.
A deeper dive into blue, purple, and black foods
Blue, purple, and black foods are often the least consumed colors in the spectrum, which is a shame. These beautifully hued fruits, vegetables, and legumes may be a bit harder to find, but they are absolutely loaded with nutrients.
Make sure to search for blue, purple, and black varieties of the natural foods you eat – things like purple carrots, purple kale, and purple cauliflower. They offer additional nutrients compared to their orange, green, and white cousins. Think of it as a treasure hunt: Make the extra effort to get these beautifully colored foods on your plate, and have fun exploring this part of the rainbow!
Many blue, purple, and black foods are known as “brain foods,” and with good reason. The nutrients found in many of these foods can enhance cognitive function, improve memory, and even decrease the risk of Alzheimer’s disease and dementia. (Note: Blue, purple, and black foods aren’t the only brain-boosters in the food rainbow. Read my article Feed Your Mind with These Healthy Brain Foods to learn about different colored brain foods throughout the rainbow.)
The powers of blue, purple, and black foods go well beyond the noggin. The nutrients found in these foods also promote cellular health, increase your longevity, reduce inflammation and joint pain, and boost your defenses against certain types of disease, including some forms of cancer.
That’s why it’s so important to get more of these powerful anti-cancer, anti-aging foods into your diet. Blue, purple, and black foods have tremendous bang for the bite!
Blue, purple, and black vegetables include black olives, eggplants, purple bell peppers, purple cabbage, purple carrots, purple cauliflower, purple kale, and purple potatoes.
Blue, purple, and black fruits include blueberries, blackberries, boysenberries, huckleberries, elderberries, figs, grapes, marionberries, plums, prunes, and raisins.
Blue, purple, and black legumes include black beans, black lentils, and black-eyed peas.
The healthy nutrients and elements in blue, purple, and black foods
Vitamin A (Carotenoids): Carotenoids are plant compounds that can convert to vitamin A in the body. Vitamin A has many functions, such as promoting healthy vision and supporting the immune and inflammatory systems, cell growth, reproduction, and bone health. Black-eyed peas, figs, plums, prunes, purple carrots, and purple kale are good sources of Vitamin A.
B Vitamins (B-Complex Vitamins): The B vitamins are like a little army of troops that provide multiple benefits to your brain, cellular health, cardiovascular system, digestive system, eyesight, muscles, and nervous system. There are eight B vitamins in all, and some or all of them can be found in a range of foods. Black beans, black lentils, black-eyed peas, eggplants, elderberries, figs, huckleberries, purple bell peppers, purple cauliflower, purple kale, purple potatoes, prunes, and raisins are good sources of B Vitamins.
Vitamin C: Vitamin C is a huge immunity booster and an antioxidant that helps our bodies fight against free radicals that can damage our cells, organs, and tissues. It has been linked to protection against cancer, heart disease, and other ailments. Vitamin C plays an important role in the natural healing process, and it is a building block for blood vessels, bones, cartilage, and muscles. Blueberries, blackberries, boysenberries, elderberries, figs, grapes, huckleberries, marionberries, plums, purple bell peppers, purple cauliflower, purple kale, and purple potatoes are great sources of Vitamin C.
Vitamin E: Vitamin E is a powerful antioxidant that protects our cells, organs, and tissues from free radicals. It also plays an important role in cardiovascular health, healthy vision, healthy skin, the reproductive system, cellular health, and immunity. Vitamin E is a building block for red blood vessels and acts as a blood thinner, which can reduce clotting. Vitamin E is fat-soluble, so it’s best to consume Vitamin E foods with a bit of healthy fat for optimal absorption. Blackberries, black olives, purple bell peppers, and purple kale are good sources of Vitamin E.
Vitamin K: Vitamin K is needed for healthy bones, and it is also a vital component in creating the blood clots that help wounds heal. Because Vitamin K is fat-soluble, it is best to consume Vitamin K-rich foods with a bit of healthy fat for optimal absorption. Blueberries, blackberries, black-eyed peas, boysenberries, grapes, marionberries, plums, prunes, purple bell peppers, purple carrots, and purple kale are good sources of Vitamin K.
Anthocyanins: Anthocyanins are phytonutrients/antioxidants that have been linked to reduced risk of cancer, protection against cardiovascular disease, and increased cognitive function. Blueberries, blackberries, boysenberries, eggplants, elderberries, grapes, marionberries, plums, purple cabbage, purple carrots, purple cauliflower, and purple potatoes are good sources of anthocyanins.
Calcium: Calcium is most commonly associated with stronger bones and teeth, but it also has many more healthy benefits for your body. It plays an important role in cardiovascular health, muscle movement, hormonal responses, and nerve function. Vitamin D helps your body absorb calcium in the most efficient way, so it’s best to pair calcium-rich foods with foods rich in vitamin D, such as mushrooms, egg yolks, and salmon. Black lentils, black-eyed peas, black olives, figs, plums, prunes, purple cauliflower, and purple kale are good sources of calcium.
Ellagic acid: Ellagic acid is an organic compound/antioxidant that has been linked to improved liver function, cellular health, and anti-inflammatory properties. Blackberries, grapes, and marionberries all help your body produce ellagic acid.
Fiber: Fiber provides a wealth of benefits to your well-being: It famously promotes gastrointestinal health (i.e. “keeps you regular”). It also helps regulate blood sugar, lower cholesterol levels, prevent heart disease, and reduce intestinal inflammation. Black beans, black lentils, black-eyed peas, blackberries, blueberries, boysenberries, eggplants, prunes, purple carrots, purple cauliflower, purple kale, and purple potatoes are all high in fiber.
Fisetin: Fisetin is a flavonoid, a chemical compound found in plants that provides antioxidant, anti-cancer, anti-aging, and anti-inflammatory effects. Grapes and red wine are good sources of fisetin.
Folate: Folate, also known as vitamin B-9 or folic acid, is an important building block for red blood cells and cellular health. Black beans, black lentils, black-eyed peas, blackberries, boysenberries, marionberries, plums, purple bell peppers, purple cabbage, and purple kale are good sources of folate.
Glucosinolates: Glucosinolates provide the liver with what it needs to get rid of toxins, and they are also helpful for your intestinal health. Studies have found that they may also help fight against some forms of cancer, especially estrogen-related cancers such as breast and uterine cancer. Glucosinolates contain sulfur, which means that most funky-smelling vegetables are good sources of these powerful compounds. Purple cabbage, purple cauliflower, and purple kale are great sources of glucosinolates.
Iron: Iron is synonymous with strength — both inside and outside the body. Your body uses it to create hemoglobin, which delivers oxygenated blood from your lungs to the rest of your body. Iron can increase your energy levels, strengthen your muscles, boost your physical performance, increase brain function, and improve your immune system. The iron found in plants is non-heme iron, which is best absorbed when combined with vitamin C. Most plant foods that contain iron also contain vitamin C, but it doesn’t hurt to add vitamin C-rich foods such as tomatoes, bell peppers, berries, citrus, or greens to aid absorption. Black beans, black lentils, black-eyed peas, black olives, figs, marionberries, prunes, raisins, purple cauliflower, and purple potatoes are good sources of iron.
Lutein and zeaxanthin: Lutein and zeaxanthin are carotenoids similar to the beta-carotene found in orange foods and the lycopene found in red foods. They help promote eye and skin health and fight free radicals that can do damage to your body. Eggplants, purple carrots, and purple kale are good sources of lutein and zeaxanthin.
Magnesium: Magnesium is a mineral that plays an important role in hundreds of chemical reactions throughout your nervous, cardiovascular, immune, and muscular systems. Black beans, black lentils, black-eyed peas, figs, plums, prunes, purple cauliflower, and purple potatoes are good sources of magnesium.
Manganese: Manganese is a mineral with antioxidant properties that plays an important role in the health of your brain, bones, reproductive system, and nervous system. Manganese is a building block for connective tissue and blood clots, and it also helps regulate blood sugar and optimize your metabolism. Black beans, black lentils, black-eyed peas, blackberries, blueberries, boysenberries, grapes, purple bell peppers, and raisins are good sources of manganese.
Potassium: Potassium is a mineral that helps optimize your heart health, and it also acts as an electrolyte that regulates your blood pressure and strengthens your muscles. Black beans, black lentils, black-eyed peas, huckleberries, plums, prunes, purple bell peppers, purple potatoes, and raisins are good sources of potassium.
Pterostilbene: Pterostilbene is a phytonutrient similar to resveratrol. Some research suggests it wards off cancer, keeps blood fats (cholesterol and triglycerides) low, and potentially helps to preserve cognition. It may also have positive effects on blood sugar. Blueberries, grapes, and red wine are good sources of pterostilbene.
Quercetin: Quercetin is a flavonoid with antioxidant effects, and it has been linked to protection against cancer, reduced risk of heart disease and high blood pressure, and anti-inflammatory benefits. Blackberries, blueberries, black olives, elderberries, grapes, and red wine are good sources of quercetin.
Resveratrol: Resveratrol is a phytonutrient that promotes healthy aging processes by reducing inflammation and blood sugar. It is also beneficial for the cardiovascular system. Blueberries, grapes (with the skin), and red wine are good sources of resveratrol.
Zinc: Zinc is a mineral that is a building block for healthy DNA. It also helps your metabolism and digestive system, and it’s essential to your cellular health, immune system, and nervous system. Black beans, black lentils, and black-eyed peas are good sources of zinc.
Special tips for getting the most nutrition out of blue, purple, and black foods
Antioxidants, antioxidants, antioxidants: Purple is the color of royalty, and purple, blue, and black foods are the kings and queens of the antioxidant world. Antioxidants are healthy because they protect the body against free radicals, harmful substances that can damage your health at the cellular level. Purple, blue, and black foods are particularly rich in anthocyanins, which protect your body against cancer and cardiovascular disease, and also boost your brain power! Blueberries, blackberries, marionberries, eggplants (with the skin), and purple cabbage are loaded with anthocyanins. Black olives are rich in polyphenols, another type of antioxidant that improves memory and cognitive function.
Purple/black rice and vegetables: The beauty of purple and black grains and vegetables, including rice, kale, carrots, cabbage, cauliflower, and potatoes is far more than skin deep. These deeper, darker varieties of whole natural foods have a wider variety of nutrients and antioxidants than their more commonly colored cousins. A deep purple or blue color is a sign that these fruits, vegetables, and legumes are more phytonutrient-dense than the typical varieties. The downside is that they are sometimes more expensive and are not always available at the grocery store, but it’s worth looking around for them. Some argue that these foods are almost like “built-in health insurance,” as they are packed with additional nutrients compared to their typical varieties.
Smaller berries and grapes pack a bigger punch: Smaller berries and grapes tend to be higher in nutrients; a plump farm blueberry is less nutritious than a smaller blueberry grown wild without pesticides. The essential phytonutrients are in the skin. Frozen and fresh blueberries are rather equivalent in phytonutrient content, so it is possible to have blueberries year round if they are bought frozen.
Berries, grapes, and wine promote healthy aging: Resveratrol is a popular purple phytonutrient that has made its way into the news for its ability to promote healthy aging processes by reducing inflammation and blood sugar. It is also beneficial for the cardiovascular system. Grapes (with the skin) and blueberries are good sources of resveratrol, as is the occasional glass of wine. Notice I said the occasional glass of wine: It’s very important to limit your alcohol consumption, as excess consumption has been linked to cancer, digestive issues, liver disease, heart disease, high blood pressure, and stroke.
Boost brain power with berries and grapes: Pterostilbene is a phytonutrient that resembles resveratrol, found in blueberries and grapes. Some preliminary research suggests it wards off cancer, keeps blood fats (cholesterol and triglycerides) low, and may help with preserving cognition. It may also have positive effects on blood sugar.
Be careful with dried prunes, figs, and raisins: When buying prunes, dried figs, and raisins at the grocery store, read the label to be sure that no preservatives (sulfites, BHT, BHA) or sugar have been added. If you are sensitive to sulfites, it is best to avoid sulfite-treated dried fruits. Pay attention to how your body responds to this food and beverage additive. For example, the sulfites in red wines cause some people to have headaches.
Explore the other colors of the food rainbow
By consuming every color in the natural food rainbow, you will be flooding your body, systems, organs, cells, and DNA with so many nourishing, healing, and restorative nutrients. Your food will become medicine! Learn how each color in the rainbow can help you experience improvements in joint pain, sleep patterns, energy levels, mood, bloating, headaches, digestive issues, weight, and other conditions.
Red Foods: Dive Deeper Into the Rainbow
Orange Foods: Dive Deeper Into the Rainbow
Yellow Foods: Dive Deeper Into the Rainbow
Green Foods: Dive Deeper Into the Rainbow
Brown, Tan, and White Foods: Dive Deeper Into the Rainbow
The Rainbow Explained: An Overview of the Benefits of Different Colored Whole Foods
