Phytochemical Compounds in Plants


Verywell / Alexandra Shytsman

Phytochemicals are naturally occurring chemicals produced by plants. Some phytochemicals give plants their pretty colors, like the blues in blueberries and the red in raspberries. Other phytochemicals give plants their distinctive aromas. These phytochemicals help plants to prosper by attracting insects and other creatures to pollinate the plants or spread the seeds.

Phytochemicals are biologically active and can affect your health when you eat the plants that contain the compounds.

Preliminary research suggests it's possible that various phytochemicals may help protect from cancer or possibly slow down the growth of cancer, as well as reduce inflammation, and help regulate hormones.

Human studies on the potential cancer-fighting properties of phytochemicals are limited. To know whether phytochemicals contain verifiable cancer-fighting benefits, more research is still needed. But emerging research has shown that phytochemicals boast important health benefits such as reduced inflammation and hormone function.

Phytochemicals are often extracted from plants and then processed and sold as dietary supplements. They're generally considered to be safe, but there's not much regulation regarding their dosages or even effectiveness, so it's important to speak with your healthcare provider before taking these supplements, especially if you have any health conditions. 

Phytochemicals in Your Diet

There are lots of different phytochemicals in all the plant foods you eat and many contain nutritional value. However, unlike vitamins and minerals, they're not considered to be essential nutrients and there aren't any established dietary reference intakes.

Fruits, vegetables, nuts, seeds, whole grains, and legumes are the best sources of phytochemicals.

There is a fair amount of evidence that eating a diet rich in plant-based foods is beneficial for your health. This benefit may be due to the essential nutrients or fiber. It's also possible that people who eat more plant-based foods also tend to be more active and more likely to maintain a healthy weight. Yet emerging research is also exploring the potential health benefits of phytochemicals as part of a health diet.


There are several groups of phytochemicals based on their chemistry. Some of the best-known phytochemicals include carotenoids, which include alpha-carotene, beta-carotene, luteinlycopene, and zeaxanthin. All of these phytochemicals can be converted to vitamin A in your body. But for the most part, plant-based vitamin A comes from the beta-carotene.

Another class of phytochemicals is the flavonoids family.

Flavonoids include:

  • Anthocyanidins, which are found in red, blue, and purple pigments of berries and grapes.
  • Flavanols, which are found in tea, chocolate, berries, grapes, and apples.
  • Flavanones, which are found in citrus fruit.
  • Flavonols that are found in lots of fruits and vegetables.
  • Flavones that are found in celery and hot peppers.
  • Isoflavones that are found in soy and legumes.

Other phytochemicals include compounds you might have read about such as:

  • Resveratrol that's found in grapes and peanuts.
  • Lignans found in seeds and whole grains.
  • Phytosterols that are used to lower high cholesterol.
  • Indole-3-carboninol that's found in cruciferous veggies.
  • Curcumin, which is found in turmeric.
  • Chlorophyll, which is found in any plants that are green.

Fiber can also be classified as a phytochemical because it's only found in plants, but sometimes it's classified as a carbohydrate. There are a number of dietary fibers including cellulose, beta-glucan, hemicellulose, pectin, gum, inulin, oligofructose, and resistant starch.

Eating a diet high in fiber will help keep your cholesterol levels in check, and improve digestive system function. Eating a meal that's high in fiber can slow down the blood sugar spikes that can occur when you eat a large amount of sugar or starch.

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