context: After non-melanoma skin cancer, prostate cancer is the most commonly diagnosed cancer in American men. It's also highly treatable if caught early. For many men, though, the standard treatments for prostate cancer -- medication, radiation, and surgery -- often come with unwanted side effects. Because of those side effects, some men wonder if alternative treatments might be beneficial. Is it possible such remedies as herbs and natural dietary supplements might help treat or slow the progression of prostate cancer? Might they delay the development of this disease? Clinical trials continue to investigate these questions. Prostate cancer is the second leading cause of cancer-related deaths among men in the United States. It is thought that virtually all men with circulating androgens (hormones) will develop microscopic prostate cancer if they live long enough. In fact, when prostatic tissue is scrutinized under a microscope after surgery (or at autopsy), cancer is found in 50% of men older than age 70. And it's found in virtually all men over age 90. Diet may account for about one-third of cancers of the prostate, large bowel, and breast. All of these cancers are more common in the Western world than in Asian countries such as Japan and China. Although cancer is influenced by both hereditary and environmental factors, studies show that Japanese men and those who eat a vegetarian diet have the lowest rates of prostate cancer. One possible explanation is the low fat content of the Asian diet. Another is that certain nutrients in the foods in these diets may help reduce the cancer risk. A healthy diet rich in nutrient-dense fruits and vegetables may reduce your risk of prostate cancer. Vitamin D3 has shown promise as a treatment for advanced prostate cancer, but is still under study. If you've been diagnosed with prostate cancer, listen to your conventional medical doctor. Your doctor will guide your treatment regimen using the latest proven cancer therapies. Some alternative treatments for prostate cancer may be harmful when used with standard cancer treatments. So, always check with your health care provider before using any natural herb or supplement. That way you can avoid drug-herb interactions. Lycopene is a powerful antioxidant. It's found in abundance in some fruits and vegetables, particularly cooked tomatoes. Some studies show that people who eat diets high in tomatoes and other fruits high in lycopene have lower cancer rates, and some researchers even believe lycopene may retard the growth of prostate tumors. However, results of several studies have not been consistent. Lycopene is found in large quantities in foods normally consumed. No side effects have been noted or precautions suggested when this "super nutrient" is eaten as part of a balanced diet. In rodent studies, scientists have demonstrated a positive effect of pomegranate in reducing cancer cell growth in mice. Studies on human cells show similar promise. This has led some researchers to recommend further exploration of pomegranate extract for human therapeutic use. As with lycopene, drinking pomegranate juice and eating the whole fruit can easily be incorporated in a balanced, healthy diet. And doing so is not harmful when the juice or fruit is consumed in moderate amounts. Several antioxidants and other nutrients have been identified as potentially helpful supplements for conditions of the prostate. Those conditions include benign prostatic hypertrophy ( BPH), or enlarged prostate. Clinical trials are being conducted to find out more about the benefits of these "super nutrients." In the U. S., men have relied more on the herb saw palmetto than on other natural therapies for relief from enlarged prostate. Men participating in several studies had better results when taking saw palmetto as compared to taking placebo. Saw palmetto hasn't been shown to prevent or treat prostate cancer. The most common side effect of saw palmetto is mild digestive distress. Saw palmetto also seems to have some health benefits when used with African plum tree bark extract. But researchers caution that not all extracts are the same. Some preparations of these herbs can have different properties. Because herbs and dietary supplements are not regulated by the FDA, there are no guarantees about the quality of natural products. The African plum tree is also known as Pygeum africanum. Its bark has traditionally been used in African cultures to treat urinary and bladder problems associated with BPH. In Europe, extract from the African plum tree bark is extensively used. It's been reported to reduce symptoms associated with BPH such as having to get up frequently at night to urinate or frequent urination during the day. Use of this herb for health reasons is so widespread around the world that the African plum tree is now endangered. African plum tree bark extract may help men deal with the discomfort of BPH. But it has not been proven to reduce the size of an enlarged prostate. Side effects noted with use of African plum tree bark include nausea and stomach upset.