According to Richard Beliveau, PhD, & Denis Gingras, PhD (Cooking with Foods that Fight Cancer), citrus fruits are packed with cancer fighting benefits, and may be among the fruits with the greatest cancer fighting potential. This is especially true in the fight against cancers of the digestive track, esophagus, mouth, and stomach cancers.

The anti cancer benefits of citrus fruits are mainly found in the significant quantities of monoterpenes and flavanones, two classes of compounds that are believed to cut the risks of cancers of the digestive track in half. These compounds reduce cancer risks in two significant ways. First, they interfere with some of the processes necessary for cancer cell growth, making it difficult for tumours to develop, and second, they inhibit inflammation, an important stimulus for cancer cell growth.

The consumption of citrus fruits has been known to cause problems for people taking various medications due to its ability to inhibit the elimination of certain substances from the bloodstream, but this same ability is also found to have anti cancer benefits under normal conditions, in that it also slows down the removal of anti cancer molecules within the body from other healthy foods, allowing them to remain in the bloodstream for longer periods of time. This ability maximizes the anti cancer benefits of other healthy foods that have been eaten. So, in addition to being an excellent source of vitamin C, citrus fruits can aid in the prevention of cancer.