Phytonutrients, also known as phytochemicals, are bioactive compounds that are produced by plants. Readily available for consumption in fruits, vegetables, and grains, phytonutrients have been found to be beneficial for our health and have been linked to a reduced risk of a variety of major chronic diseases, such as type 2 diabetes, cancer, and cardiovascular diseases.
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Phytochemicals are chemical compounds produced by plants for protection against predators and environmental threats. Although they are not critical for our health the same way vitamins and minerals are, there is evidence phytochemicals offer health benefits when we consume them, so we call them phytonutrients.
While the immune system requires a variety of nutrients to properly function and nutrient deficiencies may play a role in the development of autoimmune disease, some people with autoimmune disease may benefit from omitting certain foods from their diet. Some of these foods — many of which are nutrient-dense —contain inflammatory compounds that outweigh their nutrient density or other benefits. For example, nightshades such as tomatoes and eggplants are omitted during the AutoimmuneProtocol (AIP) diet elimination phase. Our Nutritional Therapy Practitioners are specifically trained to help guide you through an elimination protocol such as AIP. More importantly, our foundational approach revolves around addressing digestive imbalances and gut health so that you may reintroduce as many foods as possible. A diverse diet is always the end goal!
Phytonutrients are produced by plants to protect them from disease, predation, and harmful environmental conditions, so it isn’t surprising that the health benefits they offer us fall along the same lines. Thousands of phytonutrients have been discovered so far, and research has uncovered several ways they may be used to treat and prevent disease and chronic health problems.
The antioxidant properties of many phytonutrients help keep oxidants and free radicals in check. Our body is constantly exposed to oxidizing agents and free radicals. They are present in the air, food, water, and are produced by metabolic processes in our cells.Free radicals are a double-edged sword. Low to moderate levels can help fight pathogens and boost immune function. Howe ver, they can also accumulate in the body and lead to oxidative stress, damaging DNA, proteins, and fatty tissue. Oxidative stress plays a role in the development of autoimmune and other diseases.
Inflammation is our body’s biological response to infection, injury, or irritation. However, chronic inflammation can give rise to autoimmune diseases such as rheumatoid arthritis and diabetes.Research has found that phytonutrients are effective inhibitors of chronic inflammatory processes in the immune system.
Many phytonutrients are produced by plants to defend themselves against pathogens. These compounds also have antibacterial, antifungal, and antiviral effects against pathogens that humans come into contact with. Researchers have begun harnessing these antimicrobial effects to develop methods of fighting antibiotic resistant bacteria.
Some phytonutrients may behave like hormones. For example, phytoestrogens are naturally occurring plant compounds that mimic estrogen. Estrogen regulates the reproductive organs in the body, growth of healthy bones, and the breaking down of fats in the liver. When phytoestrogens are consumed, they may have a similar effect to estrogen produced by the body.
Phytonutrients in plants also act as pigments, giving fruits and vegetables their characteristic colors. Each color is caused by specific phytonutrients, for example, anthocyanins are responsible for the colors blue and purple, while carotenoids are responsible for yellow and red.
Lycopene is the phytochemical that gives fruits and vegetables their red color. Lycopene is a potent antioxidant and has anti-inflammatory properties that protect the body from oxidative stress. Lycopene has also been found to decrease “bad” low density lipoprotein (LDL) and increase “good” high density lipoprotein (HDL) cholesterol.
Lycopene may also protect the skin against ultraviolet (UV) damage from the sun. One small study found that participants who added 16milligrams of lycopene to their diet every day had less severe skin reactions to UV light over 10 weeks than a control group without the added lycopene. (Of course, consumption of lycopene-rich foods doesn’t replace sunscreen!)
Carotenoids are responsible for yellow, orange, and red color in many fruits and vegetables. Research suggests that one carotenoid in particular, beta-carotene, may protect against decline in lung function. A study done in 2017 also suggested that eating fruits and vegetables rich in carotenoids such as beta-carotene, alpha-carotene ,and beta-cryptoxanth in had protective effects against lung cancer.
Like lycopene, dietary intake of beta-carotene has protective effects against diseases that are mediated by oxidative stress, such as diabetes, cancer, and autoimmune diseases. High levels of alpha carotene are associated with longevity — one large U.S. study found that high levels of alpha-carotene in the blood were linked with a reduced risk of death over a 14 year period. Aside from its antioxidant effects, the carotenoid beta-cryptoxanthin may prevent bone loss and may have anti-inflammatory and anticancer properties.
Lutein and zeaxanthin are also part of the carotenoid family, along with beta-carotene, alpha-carotene, and beta-cryptoxanthin. Lutein and zeaxanthin are the only dietary carotenoids that reach the retina, the thin layer of tissue that lines the inside on the back of the eye. They are known to support eye health and have preventative effects against age-related macular degeneration, an eye disease that can lead to the loss of vision as we age. However, lutein and zeaxanthin also have strong antioxidant and anti-inflammatory capabilities. Zeaxanthin can also help to recycle glutathione, another important antioxidant in the body. (9, 15)
Dark green, leafy cruciferous vegetables are a good source of sulfur (isocyanate, sulforaphane, glucosinolate). Our body needs sulfur in order to synthesize certain essential proteins. These sulfur compounds break down into isothiocyanates and indoles in the gut, which are known to have antibacterial, antiviral, antifungal, and anti-inflammatory effects. (36, 52, 33)
Research suggests that sulforaphane may support heart health by reducing inflammation and lowering blood pressure. It may also have antidiabetic effects. One study found that sulforaphane reduced fasting blood sugar in patients with type 2 diabetes. (55, 41, 47)
Glucoraphanin, a glucosinolate that’s found in some cruciferous vegetables, has been found to protect the blood–brain barrier in mice with induced experimental autoimmune encephalomyelitis (used to study MS, which can’t be induced in the same way), suggesting it may reduce the risk of developing MS. (16, 40)
Anthocyanins are phytochemicals that give red, blue, and purple plants their vibrant coloring. Anthocyanins have antioxidant properties that may boost heart health and reduce the risk of developing cardiovascular-related and other chronic diseases. (26)
Anthocyanin-rich foods have been linked to reductions in inflammation and reduced blood sugar concentrations, suggesting they may also have antidiabetic effects. Anthocyanins have also been found to protect eye health. One study found that daily supplementation with pharmaceutical anthocyanins improved the visual function of individuals with normal tension glaucoma (where the optic nerve is damaged despite pressure in the eye being normal). (30, 43)
Other phytochemicals called stilbenoids are typically found in grapes and blueberries. Like anthocyanins, stilbenoids have been shown to have a variety of benefits such as protective effects on the heart and brain, as well as antidiabetic, anticancer, and anti-inflammatory properties. (4)
Allicin, a phytochemical produced when garlic is chopped or crushed, has been associated with a lower risk of coronary events in older adults. Research suggests allicin may help reduce LDL and total cholesterol levels when consumed for more than 2 months. (8, 39)
Garlic is well known for its antimicrobial effects and has historically been used to combat infectious diseases. It is also known to be effective against a variety of bacteria, such as Salmonella, Escherichia coli, and Staphylococcus aureus. (8)
Another phytonutrient that is found in many white, tan, and brown foods is quercetin. Quercetin has anti-inflammatory properties and may be effective against obesity, cancer, viruses, allergies, and high blood pressure. (5)
Serum C-reactive protein (CRP) levels are a biomarker of inflammation in the body. High CRP levels are associated with heart disease, obesity, and lupus. One study done in 2008 found that the intake of foods rich in flavonoids, such as quercetin, is associated with lower serum CRP concentrations. (12)
The thousands of phytochemicals produced by plants for their own protection may also help prevent and treat many of our own medical conditions and diseases. Phytonutrients give fruits, vegetables, grains, nuts, and other plant foods their variety of colors, so “eat the rainbow” to maximize the health benefits offered by these plentiful chemical compounds.