Berries contain a number of compounds that have been shown to prevent cancer development. These compounds can treat developed cancers as well.

In fact, these compounds can inhibit cancer in all of its stages — initiation, promotion, and progression.

In most cases, the testing has been conducted using either animal models with chemically induced cancers or animals that have had human tumors implanted in them. In these studies, the animals’ immune systems are powerfully suppressed to make them highly susceptible to the cancer.

In one such study, researchers tested six types of berries — blackberries, black raspberries, blueberries, red raspberries, strawberries, and cranberries — against implanted human colon, breast, oral, and prostate cancers.

Compounds from all of the berries reduced growth of these cancers, but the most effective were strawberries and black raspberries, especially against colon cancer.

In another study, researchers found that dried black raspberries inhibited oral, esophageal, and colon cancers in rodents. They even isolated ferulic acid and beta-sitosterol as the active ingredients in the berries that inhibited the cancers.

Both of those compounds are available as concentrated, purified supplements without a prescription.

This finding was confirmed by another study that used freeze-dried black raspberries, which inhibited esophageal cancer in rodents by 30 to 60 percent. Even more impressive was the fact that they inhibited colon cancer by 80 percent.

The researchers are now conducting trials on humans to see if they can get similar results.

Other studies have shown that blueberries inhibit melanoma metastasis and proliferation. The inhibiting factors appeared to be the anthocyanins.

Anthocyanins from blueberry and black currant juices have also been shown to inhibit the growth of ovarian and cervical cancer, as well as melanomas.

One of the most impressive studies examined the effects of 13 types of berries, including:

• Blueberry

• Gooseberry

• Blackberry

• Currant

• Cranberry

• Saskatoon berry

• Chokeberry

• Sea buckthorn

These berries were tested for their effectiveness against stomach, prostate, intestine, and breast cancers.

Blueberry, currant, cranberry, and a few others significantly reduced the growth of these cancers by inhibiting the reproduction of the cancer cells (a process called cell-cycle arrest).

One of the most important processes involved in a cancer’s growth, invasion, and spread is angiogenesis, or development of new blood vessels. Inhibiting angiogenesis has been shown to powerfully impede cancer growth, and can even lead to the death of cancers.

In one study, researchers examined six berries — blueberries, strawberries, cranberries, bilberries, elderberries, and raspberry seeds — for anti-angiogenesis properties.

All of the berries exhibited this property, but the most powerful were bilberries and blueberries, which inhibited two compounds that drive angiogenesis — vascular endothelial growth factor (VEGF) and TNF-alpha.

Chronic inflammation of the colon, called colitis, is a common cause of colon cancer. Compounds that inhibit this inflammation have been shown to prevent colon cancer from developing.

In one study, researchers examined the ability of red raspberries to inhibit inflammatory immune cells (called macrophages) taken from colitis-affected animals.

Researchers used the crude extracts of seven berries, and found that red raspberries most powerfully suppressed the inflammation and reduced the damage in the colons of these animals. This was achieved mainly by reducing the release of inflammatory substances from the macrophages.

Red raspberries also suppressed a protein complex called NF-kb, which drives inflammation.

Red raspberry extract also powerfully suppressed the formation of nitric oxide by restraining the enzyme iNOS (inducible nitric oxide synthase), which forms nitric oxide.

High levels of nitric oxide in the tissues, as opposed to within blood vessels, can drive cancer growth by stimulating inflammation and free radical generation.

Another study found that giving daily blueberry powder to men and women significantly increased the number of natural killer white blood cells (NK cells) in both the men and the women.