ABSTRACTS

HONOLULU, HAWAII. About three per cent of all Americans over the age of 65 years now suffer from Parkinson's disease (PD). Although a small proportion of cases can be traced to a genetic defect most are believed to be environmental in origin. Researchers at the Department of Veterans Affairs have just released a major report that concludes that smoking and drinking coffee provide significant protection against developing PD. Their study involved 8000 Japanese-American men who were enrolled in the Honolulu Heart Program between 1965 and 1968. The men's smoking status and intake of coffee, caffeine, and other dietary components were determined at enrollment and six years later. After 30 years of follow-up 102 of the men had been diagnosed with PD. The median age for initial diagnosis was 73.6 years (range was 54-89 years). Nondrinkers of coffee were found to have a five times greater risk of developing PD than did men who drank seven cups (4 oz servings) or more of coffee a day. Overall, nondrinkers had a two to three times greater risk of PD than coffee drinkers even after adjusting for smoking and other variables. Smoking was also found to be protective with nonsmokers having a 3.5 times greater risk of PD than current smokers. Smokers who also consumed moderate amounts of coffee (3-4 4 oz cups/day) had a risk of developing PD that was five times less than that of a nonsmoking, non-coffee-drinking man. Other forms of dietary caffeine sources were also found to be protective. The researchers speculate that caffeine exerts its protective effect through its stimulation of the central nervous system.
Ross, G. Webster, et al. Association of coffee and caffeine intake with the risk of Parkinson disease. Journal of the American Medical Association, Vol. 283, May 24/31, 2000, pp. 2674-79

DALLAS, TEXAS. The American Diabetes Association recently revised its dietary guidelines for patients with diabetes so as to include 20-35 grams per day of dietary fiber. It is estimated that the current intake of dietary fiber in the United States averages only about 16 grams per day. A team of American and German medical researchers now report that even higher fiber intakes than those recommended by the ADA can be highly beneficial for patients with type 2 diabetes. Their study involved 13 patients who were randomly assigned to follow one of two diets. Diet 1 provided eight grams of soluble fiber and 16 grams of insoluble fiber per day while diet 2 provided 25 grams of soluble and 25 grams of insoluble fiber. Both diets provided 2308 kcal/day of which 15 per cent was protein, 55 per cent carbohydrates, 7 per cent saturated fat, 17 per centcis-monounsaturated fat (olive oil), and 6 per cent polyunsaturated fat. The study participants received each diet for six weeks and then crossed over to the other diet after a one- week washout period. At the end of the experiment the researchers found that patients on the high fiber diet had improved their glucose control as indicated by a 10 per cent lower plasma glucose concentration and a 12 per cent lower plasma insulin concentration (area under the curve for 24-hour measurement). In addition, the patients on the high fiber diet also lowered their total cholesterol level by 6.7 per cent, their triglycerides by 10.2 per cent, and their LDL cholesterol concentration by 6.3 per cent. The researchers conclude that dietary guidelines for diabetics should emphasize an overall increase in dietary fiber through the consumption of unfortified foods rather than the use of fiber supplements. Dr. Marc Rendell, MD of the Creighton Diabetes Center supports this conclusion in an accompanying editorial and adds that combining a high-fiber diet with the use of foods with a low glycemic index effectively lower blood glucose concentrations synergistically.
Chandalia, Manisha, et al. Beneficial effects of high dietary fiber intake in patients with type 2 diabetes mellitus. New England Journal of Medicine, Vol. 342, May 11, 2000, pp. 1392-98
Rendell, Marc. Dietary treatment of diabetes mellitus. New England Journal of Medicine, Vol. 342, May 11, 2000, pp. 1440-41 (editorial)

HONOLULU, HAWAII. A high intake of fruit and vegetables has consistently been linked to a lower risk of lung cancer. Early research pointed to beta- carotene as the protective component, but its role as such has not been confirmed in more recent research. Now medical researchers at the University of Hawaii provide convincing evidence that it is the flavonoids contained in many fruits and vegetables that protect against lung cancer. Their study involved 582 patients with lung cancer and 582 age-, sex-, and ethnicity-matched controls. All participants were interviewed at home and filled out a food-frequency questionnaire that tabulated their intake of 242 different foods in the year prior to their diagnosis of cancer or in the case of controls, in the year prior to their interview. As expected smoking status was found to be the main risk factor for lung cancer with there being three times as many smokers in the cancer group as in the control group. After adjusting for smoking and intakes of beta-carotene and saturated fats the researchers found a clear inverse correlation between the intakes of onions, apples, and white grapefruit and the risk of lung cancer. Study participants who consumed 20 grams of onions or more per day had half the risk compared to participants whose intake was 7.5 grams/day or less. The protective effect of onions was particularly impressive in the case of squamous cell carcinoma where heavy onion eaters had only one-tenth the risk of less enthusiastic onion consumers. Apple eaters consuming 50 grams/day (about 1/3 apple) or more lowered their risk by 40 per cent compared to participants consuming 2.3 grams/day or less. White grapefruit, but not the pink variety, also lowered lung cancer risk with participants consuming 10 grams/day having half the risk of those not consuming white grapefruit at all.
The researchers conclude that quercetin is likely to be the protective component in onions and apples while naringin is likely to be the active component in white grapefruit. They do emphasize though that the strongest protective effect was seen with the whole foods (apples, onions and grapefruit) rather than with quercetin and naringin.
Le Marchand, Loic, et al. Intake of flavonoids and lung cancer. Journal of the National Cancer Institute, Vol. 92, January 19, 2000, pp. 154-60

TORONTO, CANADA. Doubts about the benefits of hormone (estrogen) replacement therapy (HRT) continue to surface. Associations between HRT and an increased risk of pancreatitis, systemic lupus erythematosus, asthma, temporomandibular pain, and general abdominal pain have been reported in recent medical literature. Medical researchers have also begun to question the validity of earlier studies "proving" the benefits of HRT; they point out that the women in the HRT groups were generally significantly healthier than the controls.
Researchers at the University of Toronto now report that women who have recently begun estrogen replacement therapy are much more likely to undergo a gallbladder operation (cholecystectomy) or appendectomy (removal of the appendix). Their study involved three groups of women whose medical data was obtained from the Ontario health administrative databases covering 800,000 women over the age of 65 years. One group of women had been prescribed levothyroxine (a thyroid medication), another dihydropyridine calcium-channel antagonists (DCCA) and the third HRT. Estrogen is known to activate inflammation and pain responses while the other two medications have no such effects. After 18 months of follow-up the researchers concluded that women on HRT were twice as likely to end up having surgery to remove their gallbladder or their appendix than were women taking the other medications. They ascribe this increased risk of surgery to the inflammatory effects of estrogen and point out that there is also evidence that new HRT recipients may initially be at an increased risk for cardiovascular disease and osteoarthritis of the hip.
Mamdani, Muhammad M., et al. Postmenopausal estrogen replacement therapy and increased rates of cholecystectomy and appendectomy. Canadian Medical Association Journal, Vol. 162, May 16, 2000, pp. 1421-24

EDMOND, OKLAHOMA. A high blood level of homocysteine has been linked to an increased risk of heart attack, stroke, and peripheral vascular disease. There is abundant evidence that high homocysteine levels can be lowered by supplementing with folic acid. Now researchers at the Lifestyle Center of America report that adopting a healthier lifestyle including eating an exclusively vegetarian diet can result in very significant reductions in homocysteine levels.
The study involved 40 participants who were part of a vegan diet-based lifestyle program. This program included a vegan diet, moderate physical exercise, stress management and spirituality enhancement sessions, group support, and exclusion of tobacco, caffeine, and alcohol. The participants were not provided with supplements of folic acid or other B vitamins.
After one week on the program the average homocysteine level among the participants had dropped by 13 per cent (from 8.66 micromol/L to 7.53 micromol/L). The drop was particularly impressive among the participants who had a high homocysteine level to begin with. Participants with a starting level higher than 9.5 micromol/L (mean of 11.3 micromol/L) showed a 19 per cent drop and patients with coronary artery disease a drop in excess of 20 per cent (these patients also had high homocysteine levels to begin with). The researchers conclude that a one-week vegan diet-based lifestyle program can result in a significant decrease in total homocysteine level.
DeRose, David J., et al. Vegan diet-based lifestyle program rapidly lowers homocysteine levels. Preventive Medicine, Vol. 30, March 2000, pp. 225-33

BOSTON, MASSACHUSETTS. Numerous epidemiological studies have concluded that high intakes of fruits and vegetables are associated with lower risks of cancer. It was originally thought that beta-carotene was the protective component, but six large-scale clinical trials have failed to confirm any cancer-protective effects. Two of the trials involving heavy smokers showed a significant 18 per cent increase in lung cancer among the smokers who took beta-carotene. One very large trial involving 22,071 American physicians showed no benefits and no harm from 12 years of supplementation with 50 mg of synthetic beta-carotene every second day.
Researchers at the Harvard Medical School have just released the results of a major study aimed at evaluating the effects of beta-carotene supplementation among women. The study involved almost 40,000 healthy female health professionals (aged 45 years or older). The women were randomized into two groups with one group receiving 50 mg of synthetic beta-carotene on alternate days and the other group receiving a placebo. The 2.1-year supplementation phase of the study was followed by a two-year observation period. At the end of the four years 747 cases of cancer and 218 cases of cardiovascular incidents (heart attack, stroke, and death) had occurred among the women. There were no significant differences in the incidence of cancer, cardiovascular events or death from all causes in the two groups. This also held true when just the smokers among the women were considered.
The researchers conclude that beta-carotene supplementation is neither harmful nor beneficial to people at average risk for cancer except in the case of prostate cancer. The Physicians' Health Study found that men who supplemented with 50 mg of beta-carotene every second day for 12 years had a significantly lower incidence of prostate cancer.
Lee, I. Min, et al. Beta-carotene supplementation and incidence of cancer and cardiovascular disease: the Women's Health Study. Journal of the National Cancer Institute, Vol. 91, December 15, 1999, pp. 2102-06

CHARLESTON, SOUTH CAROLINA. Administration of magnesium has been shown to reduce the incidence of heart surgery related arrhythmias in adults. It has also been observed that the magnesium level in the right atrial tissue is lower in adult patients with postoperative cardiac arrhythmias compared to patients without arrhythmias after heart surgery. Researchers at the Department of Pediatric Cardiology at the Medical University of South Carolina now report that children undergoing surgery for congenital heart defects develop a severe magnesium deficiency immediately after surgery. This deficiency is associated with a greater incidence of a serious arrhythmia (junctional ectopic tachycardia) and can be prevented by an infusion of magnesium sulfate immediately after completion of the surgery.
The study involved 28 pediatric patients (average age of five years) who were scheduled to undergo heart surgery with cardiopulmonary bypass (CPB). The patients were randomly assigned to receive an infusion of magnesium (30 mg/kg body weight of a five per cent saline solution administered over a period of 10 minutes) or an infusion of saline solution immediately after cessation of CPB. Blood levels of magnesium were measured in all patients before surgery, before CPB, after CPB, upon arrival in the intensive care unit (ICU), and then every four hours for 24 hours. Each patient was also monitored for arrhythmias for 24 hours with a Holter monitor.
Comparison of the results for the two treatment groups revealed that the magnesium level was significantly below normal in patients who had received saline solution (placebo) when they arrived in the ICU and for the following 20 hours. Patients who had received the magnesium infusion, on the other hand, had magnesium levels that were well within the normal range (1.6 to 2.3 mg/dL) when tested in the ICU and for the following 20 hours. There were no incidences of junctional ectopic tachycardia in the magnesium group, but four (27 per cent) of the patients in the placebo group experienced this serious arrhythmia. It stopped after a magnesium infusion. The researchers "recommend routine measurement of magnesium levels after CPB in children undergoing heart surgery, with timely magnesium supplementation in the postoperative period." [49 references]
Dorman, B. Hugh, et al. Magnesium supplementation in the prevention of arrhythmias in pediatric patients undergoing surgery for congenital heart defects. American Heart Journal, Vol. 139, No. 3, 2000, pp. 522-28

SEATTLE, WASHINGTON. Dr. John Ely of the University of Washington and Dr. Cheryl Krone of the Applied Research Institute in Palmerston North, New Zealand have cooperated to produce a fascinating report summarizing the latest research about coenzyme Q10 (ubiquinone). It is now known that the tissues and blood of an adult human contain a total of about 2000 mg of coenzyme Q10 and that 500 mg/day is required to maintain this body pool. The average diet provides only about 5 mg/day so the remainder must be synthesized internally. The ability to synthesize coenzyme Q10 declines sharply with age and a deficiency can lead to irreversible damage in the brain and other organs. Besides its essential role in the production of adenosine triphosphate (the body's "energy" molecules), coenzyme Q10 is also a powerful quencher of free radicals (50 times more effective than vitamin E). It has been found to be entirely safe in daily intakes as high as 800 mg.
Animal experiments and at least three cases involving humans have found coenzyme Q10 to be highly effective in reversing the effects of a stroke (400-800 mg/day as soon as possible after the event) and has also been found beneficial in the treatment of congestive heart failure when combined with vitamins E and C. Some fairly recent research has established that statins (cholesterol-lowering agents) depress the synthesis of coenzyme Q10 and has concluded that patients on statins need to supplement with at least 200 mg/day in order to avoid serious deterioration in heart function. [48 references]
Ely, John T.A. and Krone, Cheryl A. A brief update on ubiquinone (coenzyme Q10). Journal of Orthomolecular Medicine, Vol. 15, No. 2, Second Quarter 2000, pp. 63- 68

PERTH, AUSTRALIA. Several studies have shown that many older Australians, especially those that are housebound or in nursing homes, have a vitamin D deficiency. This is often accompanied by secondary hyperparathyroidism which in turn is a potent risk factor for osteoporosis. Medical scientists at the Royal Perth Hospital now report that low vitamin D levels may be more widespread than originally believed. Their study involved 197 people (99 men and 98 women) who donated blood between August and November 1998. The donors were between the ages of 18 and 76 years with half being under 60 years of age.
The scientists discovered that 63 donors (34 per cent) had a serum level of 25-hydroxyvitamin D (25D) below 50 nmol/L. The presence of a deficiency was not related to age. They also found that 19 out of 20 donors diagnosed with hyperparathyroidism had 25D levels below 50 nmol/L. They suggest that levels below 50 nmol/L increase the risk of secondary hyperparathyroidism and therefore osteoporosis. The scientists speculate that the campaign linking skin cancer to sun exposure is contributing to the prevalence of vitamin D deficiency because people are now shunning the sun. They conclude that vitamin D deficiency may be widespread and not just limited to institutionalized and housebound older people and that supplementation with vitamin D may have beneficial effects on a large proportion of the population.
Vasikaran, Samuel D., et al. Vitamin D insufficiency and hyperparathyroidism in Perth blood donors. Medical Journal of Australia, Vol. 172, April 17, 2000, pp. 406-07 (letter)

TORONTO, CANADA. There is some evidence from animal experiments that antidepressants may promote breast cancer tumors. One case-control study found an association between the use of tricyclic antidepressants and breast cancer risk, but the data concerning SSRIs (selective serotonin reuptake inhibitors) is inconsistent. Researchers at the University of Toronto now confirm that long-term use of tricylic antidepressants is indeed associated with an increased incidence of breast cancer. The study involved 700 women with breast cancer (aged 25 to 74 years) and 700 age-matched controls. A comparison of the use of antidepressants between the cases and the controls found no significant overall differences in breast cancer risks. However, when evaluating the data in detail the researchers discovered that women who had used tricyclic antidepressants for 25 months or more had twice the risk of developing breast cancer as had women who had not used these antidepressants. They also noted that women who had used the SSRI antidepressant paroxetine (Paxil) for more than two weeks had a seven times greater risk of breast cancer even when other possible risk factors were fully accounted for. The researchers caution that the number of women using paroxetine was quite small and recommend larger trials to confirm their initial finding. They do point out though that paroxetine stimulates prolactin secretion and is a potent inhibitor of the cytochrome P450 2D6 enzyme, both factors in an increased breast cancer risk.
Cotterchio, Michelle, et al. Antidepressant medication use and breast cancer risk. American Journal of Epidemiology, Vol. 151, May 15, 2000, pp. 951-57

JACKSONVILLE, FLORIDA. Dr. William Cheshire, a physician at the Mayo Clinic, reports on a case where a woman's trigeminal neuralgia (tic douloureux) was traced to a galvanic reaction between an amalgam filling and an adjacent gold-alloy crown. Consumption of tomatoes and other acidic foods produced intense jolts described as being like those of an "electrical battery". The jolts in turn resulted in excruciating pain in the trigeminal nerve. Replacing the amalgam filling with a composite resolved the problem. Dr. Cheshire points out that dissimilar metals in contact with saliva can form a galvanic cell which can generate electrical currents with several hundred millivolts of potential. He points out that many patients with trigeminal neuralgia describe their pain in terms of "electrical" jolts and concludes that his patient's neuralgia may well have been triggered by the galvanic reaction between the amalgam filling and the gold crown.
Cheshire, William P., Jr. The shocking tooth about trigeminal neuralgia. New England Journal of Medicine, Vol. 342, June 29, 2000, p. 2003 (correspondence)

NEWSBRIEFS

Cigars no safer than cigarettes
Cigar consumption has increased by 50% between 1993 and 1998. This spectacular growth in cigar smoking has been fuelled partly by growing affluence, partly by a concerted promotional effort, but also to a large extent because of the popular belief that cigar smoking is safer than cigarette smoking - a belief supported by the fact that cigars are not required to carry a health warning from the Surgeon General. Researchers at the Centers for Disease Control and Prevention in Atlanta now shatter the myth that cigars are safe. Their 12-year study of almost 140,000 men found that regular cigar smokers had a 5 times greater risk of lung cancer and a 10 times greater risk of cancer of the larynx than did non-smokers. Cigar smokers who inhaled also increased their risk of developing cancer of the pancreas and bladder (by factors of 2.7 and 3.6 respectively). The researchers warn that cigar smoking is gaining in popularity among high school students and that a substantial increase in cancer rates can be expected if these young people become regular cigar smokers.
Journal of the National Cancer Institute, Vol. 92, February 16, 2000, pp. 333-37

Hydroelectric power not "clean" at all
Scientists and engineers from the World Commission on Dams, an organization supported by the World Bank, warn that hydroelectric power dams may pose a greater threat to the environment than do large coal-fired power stations. They have found that the rotting vegetation trapped behind many newly created dams may release far more greenhouse gases (carbon dioxide and methane) than even the largest coal-fired plants. Using the Balbina dam in Brazil as an example they estimate that this dam will release 3 million tonnes of carbon per year into the atmosphere in its first 20 years of operation. A coal- fired power plant of similar capacity releases less than 0.35 million tonnes per year. The experts point out that the problem is magnified in warmer climates and conclude that "there is no justification for claiming that hydroelectricity does not contribute significantly to global warming".
New Scientist, June 3, 2000, p. 4

Folic acid deficiency still a problem
A recent survey found that 24 per cent of pregnant women in Newfoundland, Canada have abnormally low blood levels of folic acid. A folic acid deficiency has been implicated in the birth of babies with neural tube defects so it is not surprising that Newfoundland has one of the highest rates of this birth defect in the world. The survey also showed that almost 44 per cent of the women examined were deficient in vitamin B12. It is estimated that the average North American diet provides only about 200 micrograms of folic acid per day. Medical research has shown that at least 400 micrograms per day is required to avoid neural tube defects. These findings add to the growing evidence that the average North American diet does not provide the vitamins needed to prevent disease let alone enjoy optimum health. Says Dr. Judith Hall of the University of British Columbia "We would all benefit from a supplement of 400 micrograms of folic acid alone or in a multivitamin".
Canadian Medical Association Journal, Vol. 162, May 30, 2000, pp. 1557-59 and pp. 1571-72

Worry may lead to osteoporosis
Two researchers at the University of British Columbia have reached the surprising conclusion that girls who worry about being overweight tend to have lower bone densities than girls who don't. The researchers quizzed 51 healthy pre-teen girls, none of whom had eating disorders, about weight worries and also measured the mineral density of the girls' bones. They found a clear correlation between lower bone density and worries about being overweight. The girls that worried had on average an eight per cent lower bone density than the girls who didn't. Although the difference is relatively small it could be important says Susan Barr, one of the researchers, "over a lifetime this could be a determinant of who gets osteoporosis and who doesn't." The researchers believe that worrying can increase the level of cortisol, a stress hormone that has negative effects on bone development.
New Scientist, July 15, 2000, p. 22

Work place stress recognized in Belgium
Since March 1999 Belgian companies have been required to include attention to stress in their health and safety policies. The legal text used in the legislation describes stress as "a condition that a group of employees feels negative about, which is coupled with complaints or dysfunction in a physical, mental or social respect and which is the result of employees' not being in a position to satisfy the requirements placed on them by the work situation." The legislative decree assumes that stress arises from a poor work organization: a low level of participation, unclear job descriptions, too little feedback, too high or too low a work load, etc. Belgian employers must have a policy that remedies stress caused by work and prevents it.
European Agency for Safety and Health at Work Newsletter, No. 5, 2000, p. 11