Cell phones and the brain

Townsend Letter for Doctors and Patients, July, 2002 by John D. MacArthur

Although free radicals are a normal part of metabolism and play a vital role in many biochemical processes, the body must keep them under control. An increase in free radicals can affect various cellular and physiological processes, including gene expression, release of calcium from intracellular storage sites, cell growth, and cell death. The actual effects, however, can vary from individual to individual and may depend on one's nutritional status and the availability of dietary antioxidants.

Antioxidants

Because free radicals cause oxidation reactions which damage cells, the body removes them with antioxidants, molecules that readily donate their electrons to neutralize free radicals. These include potent antioxidant enzymes manufactured in the body, as well as vital antioxidants obtained from food.

A major study involving 3,385 Japanese-American men from the Honolulu-Asia Aging Study reinforces the value of antioxidants for the brain. Elderly men who took both vitamin C and E supplements had an 88% reduction in the frequency of vascular dementia, compared with men who did not take the supplements. The protective effect was substantially greater in men who reported long-term use of both vitamins.

Regarding the mechanism of the protective effect, Dr. Kamal H. Masaki, of the Honolulu Heart Program, and co-authors say that the study results support "hypothesized roles for cellular and molecular oxidative injury in the pathogenesis of brain aging and neurodegenerative diseases, including Alzheimer's dementia and Parkinson's dementia, and vascular dementia." (3)

EMFs and DNA

Several studies by Henry Lai and Narendra Singh at the University of Washington's Bioelectromagnetics Research Laboratory have shed new light on the biological effects of electromagnetic fields. DNA damage (single- and double-strand breaks) was observed in the brain cells of rats exposed for two hours to a 60 Hz (cycles per second) magnetic field -- the kind generated by household electric currents. This same type of DNA damage also occurred after a two-hour exposure to radiofrequency microwaves at power levels considered safe.

The researchers then found that this EMF-induced DNA damage could be blocked by treating the rats with antioxidants, including melatonin, immediately before and after exposure. Melatonin is a hormone secreted from the brain's pineal gland. As a potent antioxidant, it effectively eliminates free radicals inside cells -- suggesting that free radicals may play a role in the genetic damage caused by magnetic fields. (4, 5)

The effect of radiofrequency radiation on DNA could conceivably be more significant on neurons than on other cell types, because these nerve cells have a low capability for DNA repair, says Dr. Lai. "Since nerve cells do not divide and are not likely to become cancerous, more likely consequences of DNA damage in nerve cells are changes in functions and cell death, which could either lead to or accelerate the development of neurodegenerative diseases." (Glial cells, however, can become cancerous. These more numerous brain cells protect and support neurons.) (6)