Phytonutrients, or phytochemicals, are bioactive chemical compounds found abundantly in the plants. The word “phyto” means plant in Greek, so “phytonutrient” literally means plant nutrient. They are components that give a plant its color, taste, smell, and even texture. They also help protect them from bacteria, fungis, UV radiation, viruses and diseases. All plants like fruits, vegetables, grains, nuts, herbs and spices contain a variety of phytonutrients.
There are thousands of phytonutrients and a single food can contain hundreds of different phytochemicals. Common phytonutrients include carotenoids, flavonoids, isothiocyanates, phenols, phytates, and lignans.
Health Benefits of Phytonutrients
Several research and experimental epidemiological studies have clearly suggested that the phytonutrients are linked to enhancing body’s immunity, removing carcinogens, reducing cardiovascular disease, and repairing damaged DNA.
Flavonoids are the largest family of polyphenol compounds. They are natural compounds that provide colors and protection to fruits and vegetables.
Flavonoids have been documented to have antioxidant, anti-cancer, anti-viral, and anti-inflammatory effects on the body. There are several sub categories of Flavonoids:
- Anthocyanins: Anti-cancer and anti-inflammatory properties. It also associated with supporting cardiovascular health. Found in dark colored fruits like black currants, blackberries, blueberries, cherries, red grapes, plums, cranberries, and strawberries, as well as vegetables like cabbage, kale, and eggplant.
- Flavanols: Support heart health and prevent damage from free radicals. Found in apples, cocoa, tea, chocolate, and grapes.
- Flavanones: Prevent cells damage caused by free radicals and are found in citrus fruits.
- Flavonols: Fight inflammation and neutralize free radicals. Found in apricots, apples, black grapes, cherries, green beans, tomatoes, leeks, and broccoli.
- Isoflavones: Protect cardiovascular system from oxidation of LDL cholesterol, relieve the symptoms of menopause, as well as supporting brain and bone health. Found in soy-products like tofu, tempeh, soybeans, and soymilk.
Terpenes are one of the largest classes of phytochemicals that function as anti-oxidants to protect lipids, blood and body fluids from any damage caused by free radicals. Terpenes contain three main subgroups:
Carotenoids are plant pigments that are responsible for bright red, pink, yellow and orange colors in many fruits and vegetables. They acts as antioxidants for protecting the body against damage caused by free radicals. They protect against certain cancers, heart disease, and age related macular degeneration. Some common types of carotenoids include:
- Alpha-carotene: Protect the body against free radicals damage. Found in carrots, pumpkin, and sweet potatoes.
- Beta-carotene: It converts into vitamin A in the body which is good for vision health, strong immune system and for healthy skin, and mucus membranes. Found in leafy green and yellow vegetables (broccoli, spinach, carrots, pumpkin, sweet potato).
- Lycopene: Acts as an anti-oxidant. Found in grapefruit, tomatoes, watermelon, guava, and papaya.
- Lutein and Zeaxanthin: Protects against age-related macular degeneration. Found in black currants, blueberries, kale, and spinach.
Limonoids are natural compounds found in citrus fruits, usually in the peels. They are responsible for the fruits bitter taste. Some research shows that they could reduce cholesterol levels and prevent the growth of several forms of cancer.
Saponins are a class of chemical compound occur naturally in a variety of plant sources, from legumes, including beans, peanuts, and soy, to nightshade vegetables like tomatoes, potatoes, peppers, yams, and ginseng.
Saponins have a unique chemical structure that produces foam when mixed with water, just like a soap. It can bind with water as well as fats and oils. This means that, in the digestive tract, saponins produce an emulsification of fat-soluble molecules, preventing cholesterol from being reabsorbed. Saponins also have an antioxidant effect, and may even support bone strength and boost immune system.
Lignans are estrogen like compounds found in many plants. They contain phytoestrogens that help regulate the body’s estrogen production. Many studies have revealed that high levels of phytoestrogens in our blood help to reduce risk of breast, prostate and colon cancers. Studies have also shown that high levels of lignans can support healthy heart and weight, reducing the risk of insulin sensitivity, metabolic syndrome and diabetes. The good source of lignans are flaxseeds, sesame seed, sunflower seed, cashew, peanut, and whole grain.
Phenols are a large group of phytonutrients that gives the blue, red and violet colorations to fruits and vegetables. The phenols may protect against heart disease and reduce the risk of cancer. The foods highest in phenols are all berries, dark-skinned grapes, pomegranates, apples, apricots, cherries, peaches, red cabbage, tomatoes, and eggplants.
Isothiocyanates are phytochemicals that are created during the breakdown of sulfur-containing compounds in cruciferous vegetables like broccoli, Brussels sprouts, cauliflower, cabbage, collards, and kale. Isothiocyanates have been shown in some studies to decrease the risk of cancer by detoxifying carcinogens from the body and increasing the production of tumor suppressor proteins.
Ellagic Acid is a plant compound derived from the ellagitannins commonly found in certain berries (raspberries, strawberries), pomegranates and nuts. It appears to have anti-cancer properties, especially against prostate cancer. It also has antibacterial and antiviral properties.
Phytate or Phytic acid is a chemical found naturally in many plant foods like grains, nuts, beans, seeds and legumes. It binds with minerals such as iron, calcium, and zinc and interfere with their absorption in the body. Phytate is also known to help prevent cancer by enhancing the immune system. Phytate may increase the activity of natural killer cells which attack and destroy cancer cells and tumors.