Yours in health,
Hans Larsen, Editor

ABSTRACTS

PITTSBURGH, PENNSYLVANIA. Smoking is the leading preventable cause of disease and death in the Western world. Because of its highly addictive nature it is very difficult for most smokers to quit without assistance. Acupuncture, hypnosis, nicotine patches, nicotine gum, and nicotine sprays and inhalers have all been used as smoking cessation aids with varying degrees of success. Now researchers at the University of Pittsburgh and GlaxoSmithKline Consumer Healthcare report that a nicotine-containing polacrilex lozenge is quite effective in helping both low- and high-dependence smokers quit the habit.
The 1-year trial involved a total of 1818 smokers. The participants were classified as high-dependence if they had their first cigarette in the morning within 30 minutes of awakening and as low-dependence if they were able to go longer than 30 minutes without that first cigarette. The high-dependence group was randomized to receive 4 mg nicotine lozenges (1 lozenge every 1-2 hours for the first 6 weeks then tapering off to 3-6 lozenges a day by week 12) or placebo for 6 months. The low-dependence group received 2 mg nicotine lozenges or placebo. After 6 weeks, 46% of the lozenge users in the 2 mg group had been abstinent for at least 28 days as compared to 30% in the placebo group. The abstinence rate in the 4 mg group was 49% versus 21% in the placebo group. Increased abstinence was maintained even after one year since quitting and at least 6 months without lozenges. The researchers conclude that physicians should suggest the nicotine lozenge as an option in achieving smoking cessation. NOTE: This study was funded by GlaxoSmithKline Consumer Healthcare.
Shiffman, Saul, et al. Efficacy of a nicotine lozenge for smoking cessation. Archives of Internal Medicine, Vol. 162, June 10, 2002, pp. 1267-76

BETHESDA, MARYLAND. Cushing's syndrome is characterized by excessively high cortisol levels and symptoms such as weight gain, depression, and hypertension. Current screening tests (urine cortisol level and dexamethasone suppression screening) are only accurate to within about 30%. Researchers at the National Institutes of Health now report that measuring nighttime salivary cortisol levels can provide an accurate indication of the presence of Cushing's syndrome. The researchers studied 156 patients suspected of having Cushing's syndrome, 29 other patients known not to have the condition, and 34 healthy volunteers. They found that the nighttime (midnight) salivary cortisol levels in patients with Cushing's syndrome were invariably above 550 ng/dL (15.2 nmol/L) while non-Cushing's syndrome participants had levels at or below 220 ng/dL. The researchers conclude that nighttime salivary cortisol levels above 550 ng/dL will identify 93% of all patients that actually have Cushing's syndrome and will exclude all individuals without the disorder. They endorse the use of nighttime salivary cortisol as a simple, convenient, accurate, and cost-effective screening test for Cushing's syndrome.
Papanicolaou, Dimitris A., et al. Nighttime salivary cortisol: a useful test for the diagnosis of Cushing's syndrome. Journal of Clinical Endocrinology & Metabolism, Vol. 87, October 2002, pp. 4515-21

LONDON, UNITED KINGDOM. Toxoplasma gondii is a common parasite that infects 30-60% of the world's population. It releases eggs that are spread in cat feces and can only reproduce in cats. Up to now, medical researchers have believed that toxoplasmosis, an infection with Toxoplasma, is quite harmless except in the case of pregnant women and those with a compromised immune system. This belief is now being challenged.
A team of researchers at Oxford University has found that rats infected with Toxoplasma become more reckless and have slower reaction times thus making them easier prey for cats. A comparison of behaviour and reaction times between men and women with toxoplasmosis and those without showed that infected men were more independent and more inclined to break rules. Both men and women infected with Toxoplasma were found to have significantly slower reaction times than non-infected individuals.
A separate study carried out by a group of researchers at the University of Prague found that people with a latent toxoplasmosis infection were 2.7 times more likely to be involved in a car accident, whether as driver or pedestrian. Says Joanna Webster of Oxford University, "I definitely think there is something there. There's no reason to think that the parasite could not manipulate humans".
Randerson, James. All in the mind? New Scientist, October 26, 2002, pp. 41-43
Editor's comment: The best way of avoiding a toxoplasmosis infection is to avoid contact with cat feces, washing hands thoroughly after gardening, and avoiding raw and undercooked meat. Microfiltration of drinking water from watersheds accessible to cats would also be helpful.

PRINCETON, NEW JERSEY. Princeton University biologist Dr. Irakli Loladze believes that rising carbon dioxide (CO2) levels will make plant crops increasingly nutrient deficient and eventually lead to malnutrition for all. Over 3000 scientific studies have investigated what elevated CO2 levels do to plants. There is general agreement that plants today are exposed to about 30% more CO2 than in pre-industrial times. There is also general agreement that this higher CO2 level makes plants grow faster and bigger. The problem is, according to Dr. Loladze and other increasingly concerned scientists, that the faster growth interferes with the plant's capacity to absorb vital nutrients from the soil.
One study, which looked at growing rice in CO2 enriched air, found that the nitrogen content of the rice declined by 14% while the content of iron and zinc each declined by 17%. Iron deficiency is already the world's biggest health problem with 3.5 billion people suffering mental and physical impairment from an inadequate iron intake. Zinc deficiency, which causes pregnancy complications and poor health and stunted growth in childhood, may be just as widespread. Iodine content of plants may also be affected, potentially adding to the 700 million people who suffer from thyroid problems due to lack of iodine in their diet. An $80 million project is now underway to use genetic engineering to develop iron and zinc-rich varieties of rice, wheat, sweet potatoes, corn, cassava, and the common bean.
Lawton, Graham. Plague of plenty. New Scientist, November 30, 2002, pp. 26-29
Editor's comment: While swamping a few South Pacific islands and melting the polar ice caps may be a small price to pay for continuing our love affair with SUVs and unrestrained energy consumption, perhaps the thought of our children having no choice but to eat GM food may prod the powers that be to actually do something about global warming.

MELBOURNE, AUSTRALIA. Serotonin is the body's main "mood hormone" with a low level being strongly associated with depression. The depressive effect of low serotonin levels can be somewhat counteracted by the use of selective serotonin reuptake inhibitors (SSRIs) such as Prozac and Paxil. Seasonal affective disorder (SAD) is a highly prevalent form of depression affecting many people during the dark winter months. Analysis of the blood and cerebrospinal fluid of SAD patients has, however, failed to confirm the presence of abnormally low serotonin levels.
Australian researchers now report the results of an experiment, which, in my opinion, is one of the most elegant ones I have come across in a long time. The experiment was designed to determine whether or not brain serotonin levels are affected by sunlight exposure. It involved 101 healthy men, aged 18 to 70 years, with no history of major illness (including depression and SAD) and no current use of medications. Each participant was tested once during the one-year long experiment. On the morning of the test the participants had catheters inserted in the arteries and veins supplying and draining the brain of blood (as close to the brain as possible). Blood samples were drawn simultaneously from the two catheters and analyzed for the level of the neurotransmitters serotonin, norepinephrine and dopamine. The fact that both the supply and the return of blood to the brain were analyzed simultaneously enabled the researchers to determine exactly how much serotonin was produced in the brain under different weather conditions.
The researchers compared brain production of serotonin with mean atmospheric pressure, total rainfall, highest and lowest temperatures, and hours of bright sunlight during the day. Atmospheric pressure, temperature and rainfall were not correlated with serotonin production; however, hours of bright sunlight were, and to quite an astonishing degree. Participants who were tested on a bright day produced eight times more serotonin in their brain than did people who were tested on a dull day (395 pmol/min versus 49 pmol/min on average). Levels of norepinephrine and dopamine were not affected by any atmospheric conditions including sunlight. Brain serotonin production was, not surprisingly, highly correlated with the seasons with levels being seven times higher during the summer than during the winter. The researchers also observed that the effect of sunlight on brain serotonin production was immediate. Serotonin levels did not correlate at all with the degree of sunlight experienced on the day prior to the test, but only with sunlight level on the day of the test. The researchers conclude that the amount of sunlight exposure strongly affects brain serotonergic activity and thus underlies mood seasonality and SAD.
Lambert, GW, et al. Effect of sunlight and season on serotonin turnover in the brain. The Lancet, Vol. 360, December 7, 2002, pp. 1840-42 (research letter)
Editor's comment: There is certainly a great deal of evidence that exposure to bright light first thing in the morning can help alleviate SAD. This, however, as far as I know, is the first study that has actually provided the scientific mechanism for the beneficial effects of strong light. If I were suffering from SAD I would certainly consider investing in a properly designed light box and use it every morning during the dark fall and winter months.

SHEFFIELD, UNITED KINGDOM. There is considerable evidence that fish oils help in combating depression and other mental illnesses. What is not quite clear is whether it is eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) that is the most active component.
The standard medical therapy for depression involves the use of tricyclic antidepressants or selective serotonin reuptake inhibitors (SSRIs). These drugs, however, are not terribly effective. Prozac, for example, produces a 50% improvement in symptoms in only 38% of patients starting treatment. This is not much better than the placebo effect, which provides 50% improvement in about 25% of patients.
A team of British and Scottish researchers has just completed a study aimed at determining if the ethyl ester of EPA, ethyl-eicosapentaenoate (EEP), would be effective in strengthening the beneficial effect of standard antidepressants. The study involved 60 patients who were already being treated with SSRIs or tricyclic antidepressants. Fourteen patients received a placebo while the remaining 46 received either 1, 2 or 4 grams/day of EEP. All participants were evaluated for depression using several different scales at the beginning of the experiment and after 12 weeks. At the end of the study it was clear that the 1gram/day dosage of EEP was highly effective in reducing depression and associated conditions such as sadness, pessimism, inability to work, sleep disturbances, and diminished sex drive. In most cases, 60-70% of patients receiving 1 gram/day of EEP showed an improvement of 50% or better. This compares to only 25% of the patients on the placebo showing a 50% improvement. The degree of improvement was substantially less in the 2 grams/day and 4 grams/day groups. The researchers speculate that this could be due to the depletion of the omega-6 fatty acid, arachidonic acid, by an excess of omega-3 fatty acid (EPA), indicating that the balance between omega-3 and omega-6 is important when it comes to depression.
The researchers conclude that concurrent treatment with 1 gram/day of EEP is effective in reducing depression in patients who are still depressed despite treatment with standard medications. They are now planning on evaluating EEP on its own as a treatment for depression.
Peet, M. and Horrobin, DF. A dose-ranging study of the effects of ethyl-eicosapentaenoate in patients with ongoing depression despite apparently adequate treatment with standard drugs. Archives of General Psychiatry, Vol. 59, October 2002, pp. 913-19

BALTIMORE, MARYLAND. Several studies have shown that regular fish consumption protects against cardiovascular disease. Other studies have shown that consuming mercury-contaminated fish increases the risk of coronary heart disease. The beneficial effect of fish consumption is believed to be due to the presence of the omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the tissue of fish and shellfish. Two recent studies have attempted to answer the question "Are the beneficial effects of fish oils (EPA and DHA) outweighed by the negative effects of mercury"?

The first study, carried out by a team of researchers from eight European countries, Israel and the United States, involved 684 men who had suffered a first non-fatal heart attack and 724 matched controls. All participants had their mercury level measured in toenail clippings and their level of DHA measured in a fat tissue sample taken from the buttock. Participants with a mercury level of 0.66 mcg/gram were found to have twice (odds ratio of 2.16) the risk of having a first heart attack when compared with participants having a mercury level of 0.11 mcg/gram. This risk assessment was arrived at after adjusting for age, DHA level in adipose tissue, body-mass index, waist:hip ratio, smoking status, alcohol intake, HDL cholesterol level, diabetes, history of hypertension, family history of heart attack, blood levels of vitamin E and beta-carotene, and toenail level of selenium.
The research team also found that participants with a high (0.44% of total fatty acids) fat tissue content of DHA had a 41% lower risk of having a first heart attack than did those with a low (0.10% of total fatty acids) fat tissue level of DHA. This risk assessment was arrived after adjusting for all other known risk factors including toenail mercury level.
The researchers point out that the main sources of mercury are occupational exposure (dentists), exposure to silver-mercury amalgam in dental fillings, and fish consumption. They conclude that the health benefit of fish consumption is significantly diminished if the fish is high in mercury. They also confirm the cardioprotective effect of fish oils (DHA).

The second study was part of the Health Professionals Follow-Up Study begun in 1986 as a cooperative venture between the Harvard School of Public Health, the Brigham and Women's Hospital, and Harvard Medical School. The study involved 33,737 male health professionals who had toenail clippings analyzed for mercury in 1987. After 5 years of follow-up 470 participants had been diagnosed with coronary heart disease. The researchers observed that dentists, who are habitually exposed to mercury, had toenail mercury levels (0.91 mcg/gram) that were twice as high as the levels found in non-dentists (0.45 mcg/gram). They also found a direct relationship between fish consumption and mercury level with participants consuming an average of 357 grams (3/4 lb) of fish per week having a level of 0.75 mcg/gram while those who consuming 145 grams (1/3 lb) per week had a level of 0.29 mcg/gram. After adjusting for age, smoking and other risk factors for heart disease the researchers conclude that there is no clear association between total mercury exposure and the risk of coronary heart disease, but that a weak relation cannot be ruled out.
Guallar, E, et al. Mercury, fish oils, and the risk of myocardial infarction. New England Journal of Medicine, Vol. 347, November 28, 2002, pp. 1747-54
Yoshizawa, K, et al. Mercury and the risk of coronary heart disease in men. New England Journal of Medicine, Vol. 347, November 28, 2002, pp. 1755-60
Bolger, PM and Schwetz, BA. Mercury and health. New England Journal of Medicine, Vol. 347, November 28, 2002, pp. 1735-36

Editor's comment: The two studies clearly do not agree as to whether high mercury levels are associated with an increased risk of coronary heart disease. I am inclined to believe that they are. Furthermore, there is compelling evidence of significant associations between high mercury levels and Alzheimer's disease, Parkinson's disease, congestive heart failure, kidney damage, hearing loss, and high blood pressure. So definitely, mercury, from whatever source, is a very bad actor and should be avoided. The joint European/Israeli/US study clearly confirms that DHA (fish oil) is protective against a first heart attack, so regular consumption of low-mercury-level fish is still a healthy option. An alternative approach to obtaining DHA (and EPA) on a regular basis is to supplement with 1 gram/day of a high quality, molecular distilled, non-rancid fish oil containing a minimum of 220 mg EPA and 220 mg DHA. Reliable sources of such fish oils can be found at www.consumerlab.com/results/omega3.asp and at www.coromega.com
To be on the safe side it is best to eat fish and shellfish with an average mercury content of less than 0.10 ppm. Unfortunately, there are not too many species left that fulfill this requirement. King crab, scallops, catfish, salmon (fresh, frozen and canned), oysters, shrimp, clams, saltwater perch, flounder, and sole are all good choices. Salmon is my favourite because of its combination of a low mercury content with a high level of beneficial EPA and DHA. The following fish species should be avoided: tilefish, swordfish, king mackerel, shark, grouper, tuna, American lobster, halibut, pollock, sablefish, and Dungeness and blue crab. Limited sampling of the following also indicated high mercury levels: red snapper, marlin, orange roughy, saltwater bass. Atlantic cod, haddock, mahi mahi, and ocean perch have mercury levels around 0.18 ppm, so should be eaten in moderation. For more on mercury content of fish see www.cfsan.fda.gov/~frf/sea-mehg.html

DENVER, COLORADO. It is estimated that about 16% of older adults are vitamin B12 (cobalamin) deficient. This deficiency is mostly related to an inability to absorb cobalamin bound to food. Several experiments have shown that this problem does not affect people's ability to absorb free or synthetic cobalamin. A lack of vitamin B12 can lead to megaloblastic anemia and, if untreated, to irreversible neurological damage that may mimic Alzheimer's disease.
There is ample evidence that injections of cobalamin can quickly correct a deficiency as can oral supplementation with 1-2 mg/day. It is not clear, however, whether smaller amounts, such as the 25 mcg or so found in multivitamins, are sufficient to correct a deficiency.
A team of researchers from the universities of Washington and Colorado has just released a study designed to determine just how much oral cobalamin supplementation is required to reverse a deficiency. The study involved 23 older patients who had been diagnosed as being vitamin B12 deficient (serum cobalamin level less than 221 pmol/L and serum methylmalonic acid [MMA] level greater than 271 nmol/l). All participants received 25 mcg/day of cobalamin during the first 6 weeks, 100 mcg/day during the next 6 weeks, and 1000 mcg/day during the final 6 weeks of the study. Two participants achieved normal MMA levels with the 25 mcg/day dose, an additional 5 with the 100 mcg/day dose, but it took 1000 mcg/day (1 mg/day) before an additional 12 regained normal MMA levels. Thus 19 out of 23 patients (83%) normalized their MMA level and eliminated their vitamin B12 deficiency at a daily intake of 1000 mcg/day. The 1000 mcg/day dose was also effective in lowering homocysteine level in 75% of the patients, but folic acid supplementation was required in 4 of the patients in order to bring homocysteine concentrations down to an acceptable level.
The researchers conclude that most cobalamin-deficient older people require more than 100 mcg/day of oral cobalamin to correct their deficiency.
Rajan, S, et al. Response of elevated methylmalonic acid to three dose levels of oral cobalamin in older adults. Journal of the American Geriatrics Society, Vol. 50, November 2002, pp. 1789-95

NEWSBRIEFS

Diesel fuel not so clean after all
Diesel fuel is generally considered to be more environmentally friendly than gasoline. It produces about 6% less carbon dioxide when burned than do gasoline and diesel- powered cars and gets much better mileage as well. Mark Jacobson, an environmental engineer at Stanford University, now challenges the myth of diesel "superiority". He found that diesel engines emit 25 to 400 times more soot particles than do gasoline engines and that 1 gram of black carbon (soot) is 360,000 to 840,000 times as powerful a global warming agent as is 1 gram of carbon dioxide. Says Jacobson, "You definitely can't ignore carbon dioxide, but controlling soot could be the most effective way to slow global warming".
New Scientist, November 2, 2002, p. 9

Nicotine patches for exams
Researchers at the Medical College of Wisconsin suggest that smokers who are prevented from smoking during an examination or similar demanding task might perform better if they are wearing a nicotine patch. Elliot Stein and his colleagues scanned the brains of smokers while they were doing complex cognitive tasks. Smokers wearing a nicotine patch did better and also found the experience less emotionally draining than did smokers who did not wear a patch.
New Scientist, November 2, 2002, p. 25

St. John's wort and cancer drugs
Dutch researchers report that St. John's wort, a popular herbal antidepressant, can markedly reduce the effect of the chemotherapy drug, irinotecan. Their experiment involved 5 cancer patients (2 with lung cancer, 2 with colorectal cancer, and 1 with sarcoma). The patients received 300 mg of St. John's wort 3 times daily for 3 weeks prior to one of their chemotherapy treatments. The researchers found that the blood plasma level of SN-38, the active metabolite of irinotecan, was 42% lower when the patients had previously taken St. John's wort than when they had not. They conclude that patients undergoing chemotherapy should not be taking St. John's wort. Other researchers have observed that it also interferes with the action of the popular cholesterol-lowering drug, simvastatin.
Journal of the National Cancer Institute, Vol. 94, August 21, 2002, pp. 1187-88 and 1247-49

Diet implicated in acne
Acne affects about 60% of 12-year-olds and 95% of 18-year-olds in modern societies. Acne, on the other hand, is virtually unknown in primitive societies where refined sugar and grains are not available. Researchers at Colorado State University believe that highly processed breads and cereals are to blame for the acne epidemic. They point out that these foodstuffs release a flood of sugar, which in turn triggers the production of inordinately large quantities of insulin and insulin-like growth factor (IGF-1). IGF-1 helps create an excess of male hormones, which in turn helps produce excess sebum, a greasy goop much favoured by acne-promoting bacteria. Australian researchers are about to put this hypothesis to the test. They will put 60 teenage boys with acne on a low carbohydrate diet to see if this makes a difference. Highly refined carbohydrates have also been blamed for contributing to the risk of developing type 2 diabetes and short-sightedness.
New Scientist, December 7, 2002

Europe to proceed with labeling of GM products
The European Union's agriculture ministers have approved rules for the mandatory labeling of foods containing more than 0.9% of genetically modified components. The rules will become law when the European Parliament, almost certainly, approves them in March 2003. "I feel strongly that our citizens need to be able to make this choice", says David Byrne, EU commissioner for consumer protection. The US State Department and GMO producers are, not surprisingly, up in arms about the new legislation and warn of a trade war and action through the World Trade Organization if it is not repealed. Greenpeace and other opponents of genetic engineering are, equally not surprisingly, elated about the law. Says Lorenzo Consoli of Greenpeace, "The times when you could sneak millions of tons of GM soybeans and maize (corn) into the food chain are definitely over".
New Scientist, December 7, 2002

Go easy on snail consumption!
Soil contaminated with heavy metals is generally believed to be fairly innocuous to animal life unless the contaminants are dissolved or suspended in water percolating through the soil. French researchers now challenge this assumption. They allowed snails to rummage around in a drum filled with cadmium contaminated dry soil. After 2 weeks they analyzed tissue from the snails and found that they had absorbed a significant amount of cadmium supposedly tightly bound in the dry soil. Says Ian Pulford of the University of Glasgow," This means that more cadmium then predicted is getting into the food chain". Cadmium can cause anemia and kidney damage. Further studies are now underway to see whether other heavy metals such as mercury, lead, copper, and zinc also enter the food chain from contaminated soils at a rate much greater than previously assumed.
New Scientist, December 21/28, 2002, p. 14

Powerful white wine
Several studies have shown that regular wine consumption helps protect against heart disease. Red wine is believed to have a stronger protective effect than white wine due to its higher content of powerful polyphenol antioxidants, which are concentrated in the skins of the grapes. Researchers at the University of Montpellier in France have now managed to produce a Chardonnay that has four times the polyphenol content of a normal Chardonnay. The new process does not involve genetic engineering, but merely alters the initial processing of the grapes. The wine, Paradoxe Blanc, is now available commercially and is expected to be just the first of a new generation of wines with a higher content of natural antioxidants.
New Scientist, December 14, 2002, p. 7

RESEARCH REPORT

References