Phytochemicals and cancer: What you should know

You may not have heard of phytochemicals, but it’s likely you eat them every day.

Phytochemicals, also called phytonutrients, are the potentially helpful compounds found in plant foods. They may help prevent chronic diseases, including cancer.

These can be found in vegetables, fruits, beans, grains, nuts and seeds. But the type and amount of phytochemicals in different plants varies. No single plant food can protect you from disease. You can get the most protection by eating a variety of plant foods. 

More research is needed to determine how phytochemicals work. What most researchers do agree on is the benefits.

Potential benefits of phytochemicals include:

• Strengthening the immune system
• Reducing inflammation
• Preventing DNA damage and helping DNA repair
• Slowing cancer cell growth
• Regulating hormones
• Preventing damaged cells from reproducing  

There’s no specific recommendation from the medical community when it comes to phytochemicals. But the American Cancer Society recommends eating a diet high in vegetables and fruits.

“If you’re eating a high number of vegetables and fruits, then you’re getting a high number of phytochemicals,” says Lindsay Wohlford, MD Anderson wellness dietitian.

Types of phytochemicals

There are several types of phytochemicals. Each one helps your body in a different way.

Carotenoids

You may have heard of beta-carotene, lycopene, lutein and zeaxanthin. They’re all types of carotenoids. Carotenoids inhibit cancer growth, improve immunity, support vision and promote skin health. They can be found in broccoli, carrots, cooked tomatoes, leafy greens, sweet potatoes, winter squash, apricots, cantaloupe, oranges and watermelons.

Flavonoids

Anthocyanins, quercetin and catechins are all types of flavonoids. They inhibit tumor growth, reduce inflammation and boost immunity. Apples, onions, soybeans, coffee, tea and citrus fruits like oranges and lemons are all sources of flavonoids.

Indoles and glucosinolates

Indoles and glucosinolates, like other phytochemicals, can help lower your cancer risk. They are known to prevent tumor growth and decrease production of cancer-related hormones. They can be found in broccoli, cabbage, kale, cauliflower and Brussels sprouts.

Inositol

Phytic acid is a type of inositol. Inositols prevent cell damage and can be found in bran from corn, oats, rice, rye and wheat, as well as nuts and soybeans.

“Remember, phytochemicals aren’t just found in vegetables and fruits. They’re found in all plant foods,” Wohlford says.

Isoflavones

Like indoles and glucosinolates, isoflavones inhibit tumor growth and limit the production of cancer-related hormones. They’re typically found in soybeans and other soy products.

Polyphenols

Ellagic acid and resveratrol are two types of polyphenols. They can prevent cancer formation and inflammation. They’re typically found in green tea, grapes, wine, berries, citrus fruits, apples, whole grains and peanuts.

When it comes to phytochemicals, the key is to get them from whole foods -- not supplements.

“It’s important to make sure you’re eating a variety of vegetables,” Wohlford says. “An easy way to do that is to always make sure you have a colorful plate.” 

Request an appointment at MD Anderson's Lyda Hill Cancer Prevention Center online or call 877-632-6789.

Use this infographic to make a healthy salad and add more phytochemicals to your diet.