According to the American Cancer Society (ACS), more than 1,500 Americans die from cancer each day. For advanced metastatic cancers, the prognosis is typically between one and two years. “Chemotherapy can improve survival for many of these individuals, but this often comes at the expense of toxic side effects that can at times be more frightening than the disease itself. However, some physicians have found that patients who receive antioxidant-rich nutrition experience fewer side effects during and after chemotherapy. Many also believe that treatment response and survival are also improved,” Dr. Block notes.

There is a growing body of scientific research to back this up, including the gold standard of evidence-based medicine — randomized controlled clinical trials. “Glutathione has been shown to significantly reduce the various toxic effects of cisplatin and other chemotherapy drugs in six randomized controlled clinical trials to date. Not one of these studies found any sign of interference between glutathione and the various chemotherapy drugs,” Dr. Block says. He adds that studies of the potent antioxidant called melatonin have been even more favorable, including multiple studies showing significant improvements in both outcome and survival in advanced cancer patients undergoing chemotherapy.

The numbers of studies showing positive results of cancer therapies supplemented with antioxidants is far larger once non-randomized studies are included. “Although those trials are not considered the gold standard for medical evidence, it’s worth noting that virtually all of them suggest favorable outcomes or at least no interference with chemotherapy,” says Dr. Block.

So where does the idea come from that supplements could be harmful to cancer patients? Dr. Block explains that some chemotherapy agents create free radicals or similar molecules called reactive oxygen species (ROS). ROS are highly reactive and unstable forms of oxygen that have the capacity to damage genes and other cell structures. These in turn cause the intended cellular damage to cancer cells. Because antioxidants are used to counteract the damaging effects of ROS, some researchers assume concurrent use of antioxidants should limit the effectiveness of chemotherapy drugs that rely on ROS and may advise against the use of antioxidants with all chemotherapy agents, regardless of whether or not they create ROS. Read the rest of this entry »