Fruits, Vegetables, and Cancer: Nutrients That Can Reduce Risk of Tumor Growth

A healthy body needs a balanced diet. This philosophy explains how fruits and vegetables are staple foods on the table. These edibles give nutrients to our bodies that the usual meat and grains cannot provide. Because of these nutrients, scientists have been gathering data on how essential fruits and vegetables really are. Inevitably, they also looked into their effects on cancer. Researchers specifically looked into the nutrients that fruits and vegetables have. These nutrients may affect cancer cells in one way or another. To provide an overview, we will also look into which specific cancers these foods can affect.

Fruits, Vegetables, and Cancer Overview

To answer the question right away, there is still limited evidence regarding the role of some fruits and vegetables against cancer. However, scientists still continue their research. In fact, research continues as an international effort through the World Cancer Research Fund (WCRF).

In 2018, the WCRF published a detailed report on the state of cancer relating to nutrition and diet. According to the report, most of the types of cancer had little to no evidence concerning fruit and vegetable consumption. These are the following cancers with limited evidence that a greater intake of fruits or vegetables can decrease risks:

  • Decrease in Cancer Risk from Eating Non-starchy Vegetables:
    • Mouth, pharynx, and larynx cancer
    • Nasopharynx cancer
    • Esophageal cancer
    • Breast cancer (pre and postmenopausal)
  • Decrease in Cancer Risk from Eating Non-starchy Vegetables or Fruits:
    • Squamous Cell Carcinoma in the Esophagus
    • Lung cancer

Examples of non-starchy vegetables include broccoli, okra, eggplant, and green leafy vegetables. This does not include potatoes and yams. The report also specifies that a “greater intake” of these vegetables and fruits amounts to 400 grams combined for a day. 

Key Nutrients With Evidence Against Cancer

While there is still limited evidence against cancer, researchers are looking into the specifics of the case. Currently, scientists have focused on key compounds that may present anticancer properties. These compounds found in fruits and vegetables are phytonutrients. These are nutrients only found in plants. 

Research authors have explained these nutrients in a dedicated chapter from a 2021 Food Bioactive Book. They explain that these phytonutrients may provide benefits against cancer since they have proven effectiveness in the form of drugs. Although they are seeing success, these studies are still under ongoing review. 


Quercetin is a compound called flavonoid that is found in most fruits and vegetables. These include apples, raspberries, cherries, broccoli, tomatoes, and green leafy vegetables. Scientists already have extensive research on the compound regarding its antioxidant and anti-inflammatory properties. Specifically for anticancer properties, these are the specific cancers that quercetin affects:

  • Colorectal Cancer: quercetin can target multiple intracellular components of a colorectal cancer cell. This can lead to automated cancer death (apoptosis) and reduced metastasis.
  • Breast Cancer: quercetin has shown effects in reducing breast cancer in several case-control studies. Scientists have also proposed it as an alternative treatment.
  • Prostate Cancer: quercetin exhibits the capacity to inhibit human prostate cancer cells by restricting its ability to create blood vessels for itself. 
  • Gastric Cancer: in vivo and in vitro assays on quercetin have shown effects of inhibited cell growth, induced apoptosis, and necrosis of gastric cancer cells. 
  • Oral Cancer: quercetin can inhibit cancer cell viability, migration, and invasion. The compound fights against cancer cells by enhancing the expression of a certain gene called miR-16. 


This phytonutrient is normally present in grapes, peanuts, and berries. Humans have long been a benefactor of resveratrol as a usual component of one’s diet. It has recently surged in popularity due to its antioxidant properties. The anticancer activities of resveratrol rely on several other properties. These include anti-inflammatory, estrogenic, and antioxidant/pro-oxidant properties. In terms of antitumor properties, the following are the specific cancers that resveratrol can affect:

  • Colorectal Cancer: daily consumption of food with resveratrol has shown anticarcinogenic effects in several studies.
  • Breast Cancer: researchers are eyeing the use of resveratrol and other chemotherapeutic agents to decrease treatment resistance and side effects. 
  • Prostate Cancer: when combined with docetaxel, resveratrol can upregulate pro-apoptotic genes. Both can also downregulate anti-apoptotic genes against prostate cancer cells.


A lot of phytonutrients can be put in the carotenoid group. These include lycopene, beta-carotene, alpha-carotene, lutein, zeaxanthin, and cryptoxanthin. These are the same pigments that give color to our fruits and vegetables. A diet rich in carotenoids often has many benefits for the immune system and eye health. 

Specific to our discussion, we will look into the effects of lycopene against cancer. Lycopene is a pigment present in pink, orange, and red fruits and vegetables. These include red bell peppers, tomatoes, red cabbage, melons, papayas, and peaches. Lycopene affects different cancers in the following ways:

  • Breast Cancer: carotenoids such as lycopene can affect different proteins responsible for breast cancer cell growth. 
  • Prostate Cancer: lycopene supplements for prostate cancer patients have shown effectiveness against cancer cell aggressiveness. 
  • Ovarian Cancer: although still controversial, the effect of lycopene has shown the capability to reduce the risk of ovarian cancer.


This is a phytonutrient that shares the same characteristics as insoluble dietary fibers. As such, they are essential to a person’s gut health. Lignans are present in flaxseeds, olive oils, berry fruits, cashew nuts, and sesame seed oils. This compound has a lot of benefits, such as antioxidant, antimutagenic, anti-hepatotoxic, anti-aging, anti-inflammatory, and chemopreventive properties. 

Lignans work within the gut microbiome. As these interact, they produce metabolites beneficial against cancer. This combination affects action mechanisms, enzyme regulation, inflammatory cytokines, and target pathways. Specifically, lignans can affect specific cancers through:

  • Breast Cancer: although it still needs much research, recent studies on the effects of lignans against breast cancer cells in mice have shown positive results.
  • Gastrointestinal Cancer: lignans are beneficial for the gut microbiome, and these have shown anticancer activities in the gastrointestinal regions.
  • Lung Cancer: the use of lignans in radiotherapy against cancer has shown successful results in reducing the side effects of the treatment.

Click here for our blog Disclaimer.