Phytonutrients are chemicals plants produce to protect themselves against germs, fungi, disease, and other threats. When people eat plant-based foods, they benefit from the healthy properties of these compounds.

Aside from fruits and vegetables, other foods that contain phytonutrients include whole grains, nuts, beans, and tea. Most people associate phytonutrients with antioxidant properties, vitamins, and essential minerals. However, they also contain carbohydrates, proteins, amino acids, and fatty acids.

Researchers estimate that grains, fruits, and vegetables contain more than 5,000 different types of phytonutrients. However, some whole foods may contain up to 25,000 individual phytonutrientsTrusted Source.

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Phyto is the Greek word for plantTrusted Source, and phytonutrient means nutrients from plants. While plants contain vitamins and minerals that are essential for survival, phytonutrients help keep the body working properly and can help prevent some diseases.

Phytonutrients are bioactive compounds that build up in different parts of the plant — they have disease-protecting or defensive properties. When people consume phytonutrients, they may benefit from the following:

People may know of phytonutrients by certain common terms. Some of these terms, such as antioxidants or phytochemicals, describe the properties of phytonutrients. While others are the actual names of individual phytonutrients, such as:

  • catechins
  • flavonoids
  • flavones
  • isoflavones

There are more than 600Trusted Source different carotenoids. Carotenoids give plants pigmentation and color, which typically rangesTrusted Source from orange to red. Researchers know the most about these carotenoids:

  • α-carotene
  • β-carotene, the body converts this into vitamin A
  • lycopene
  • lutein
  • zeaxanthin

Carotenoids can accumulate in plant petals, leaves, and in fruits. Foods that are rich in carotenoids include:

  • carrots
  • spinach
  • tomatoes
  • parsley and basil herbs
  • kale
  • Brussels sprouts
  • squash
  • sweet potatoes

Carotenoids can act as antioxidants, and β-carotene may indirectly benefit the immune system as the body converts it into vitamin A. Vitamin A is essential for the development of immune cells, including macrophages and neutrophils.

Ellagic acid may have anti-tumor properties, which can trigger apoptosis, or cell death, in cancer cells. To be more specific, researchers have observedTrusted Source these properties in cases of liver cancer, where ellagic acid may be able to stop cancer-causing cells in the liver from multiplying. However, more studies are necessary to support these findings.

Ellagic acid is found in the following foods:

  • strawberries
  • raspberries
  • blackberries
  • cranberries
  • goji berries
  • pomegranates
  • grapes
  • walnuts
  • the mushroom fistulina hepatica

More safety studies are necessary to determine how ellagic acid interacts with other cancer medications, especially at high concentrations, for example in pomegranate juice.

Researchers have associatedTrusted Source resveratrol with protective cancer properties in addition to preventing cardiovascular disease.

Scientists have also noted its antioxidant, immunomodulatory, and anti-inflammatory effects may also help with:

However, more research is necessary to determine exactly how effective resveratrol is in preventing these conditions or reducing their symptoms.

Foods that contain high levels of resveratrol include:

  • blueberries
  • peanuts
  • grapes
  • red wine

Plants produce flavonoids to grow and defend themselves against plaque. Flavonoids build up in several parts of the plant, and onions and tea are especially rich in them.

These foods and drinks contain flavonoidsTrusted Source:

  • cocoa
  • onions
  • tea
  • wine
  • grains

Researchers have associated several benefits with flavonoids, and manufacturers use them in many products, including pharmaceuticals, medicines, and cosmetics. Generally, flavonoids have the following properties:

  • antioxidative
  • anti-inflammatory
  • antimutagenic
  • anticarcinogenic

Because of this, they may have applications in:

  • diabetes
  • cancer
  • cardiovascular disease
  • neurodegenerative disorders

Further research is necessary to determine how flavonoids exert their effect, as researchers do not fully understand why they affect certain conditions more than others.

Phytoestrogens are very similar to the hormone estrogen. Therefore, they can have estrogen-like effects, which may alter the amount of estrogen the body makes.

The use of phytoestrogens has been increasing, as they are needed for cattle feed as well as general human consumption.

Foods that contain phytoestrogens includeTrusted Source:

  • legumes
  • soy
  • vegetables
  • fruits
  • cereals

The conditions phytoestrogens may help with include:

However, more research is necessary to determine how phytoestrogens help with these health conditions.

Cruciferous vegetables are rich in glucosinolates — which contributes toTrusted Source their odor and bitter flavor. Researchers know of 130 glucosinolates. However, some of them exist in plants that humans do not consume.

Freezing vegetables during processing can retain more glucosinolates than refrigeration. During cooking, steaming is best for retaining these nutrients instead of boiling, microwaving, or pressure cooking.

Foods that contain glucosinolates include:

  • arugula (rocket leaves)
  • bok choy
  • broccoli
  • Brussels sprouts
  • kale
  • kohlrabi
  • radish
  • turnips
  • wasabi
  • watercress

The conditions glucosinolates may help with include:

Researchers, however, need to conduct more studies to fully understand how glucosinolates help with these disorders.

Phytonutrients come from plants. Plants make them for several reasons, including defense against microbes and disease. Phytonutrients can also aid growth and generally make plants more resistant to their environment.

Consuming phytonutrients can benefit humans. In fact, manufacturers are already using some phytonutrients in cosmetics and pharmaceutical products. However, more research is necessary to determine their effectiveness in treating diseases and other health conditions.