News Briefs – October 2010

SELENIUM SUPPLEMENTS REDUCE BLADDER CANCER RISK 

A study has found that, depending on a person’s individual characteristics, increasing his/her selenium intake can lower the risk of bladder cancer by as much as 39 percent. (Selenium is an essential micronutrient that is incorporated into about 25 proteins, called selenoproteins, most of which are enzymes with antioxidant properties that prevent cellular damage caused by the by-products of oxygen metabolism.) Seven previous studies were analyzed to evaluate selenium levels – measured in toenails and blood – and the corresponding incidence of bladder cancer. Most of the subjects were from the U.S. but some were from Belgium, the Netherlands and Finland. Gender-specific differences seemed to account for the greater cancer-protective effect of selenium in women. Further studies are required to determine the all-important optimum dosage of selenium. This study was released on August 31, 2010 and will be published in a future issue of the journal, Cancer Epidemiology, Biomarkers & Prevention.

VITAMIN D MAY BOOST HEART FAILURE SURVIVAL RATES

A study has found that heart failure patients with reduced levels of vitamin D have lower rates of survival than patients with normal vitamin D levels. As a result, researchers suggest that a low intake of vitamin D may be a factor in the development, and outcome, of heart failure. Vitamin D is produced by the skin when it is exposed to the natural ultra violet-B, or UV-B, radiation from the sun. Most tissues and cells have a vitamin D receptor; and evidence suggests vitamin D reduces the risks of several chronic illnesses such as common cancers, autoimmune diseases, kidney diseases, chronic infectious diseases, high blood pressure – and apparently, heart failure. The study team described the evidence of a protective effect from vitamin D as “compelling” and recommended that heart failure patients should be advised to take vitamin D supplements and eat oily fish or eggs. The study was presented August 31, 2010 at the annual congress of the European Society Cardiology.

CALCIUM AND VITAMIN D INCREASE DIET-INDUCED WEIGHT LOSS

A study has concluded that greater intakes of dairy calcium and higher blood levels of vitamin D produce a substantially greater weight loss than the loss experienced by those with lower calcium and vitamin D intakes. (Vitamin D is a fat-soluble vitamin that is found in supplements and in a few foods such as cod liver oil, sockeye salmon, mushrooms, mackerel and tuna fish.) The six-month study used techniques that ruled out the influence of other factors such as age, sex, body mass index, total fat intake and diet type. Blood levels of vitamin D and dairy calcium intake were found to be separate factors affecting increased weight loss; that is, each nutrient had its own specific effect. This study was released September 1, 2010, and will be published in a future issue of the American Journal of Clinical Nutrition. The full-text version is now available online, with subscription or payment of an access fee, at https://bit.ly/coMR3d

IRON DEFICIENCY LINKED TO CHRONIC HEART FAILURE

A study has found that iron deficiency is a factor among chronic heart failure (CHF) patients in terms of poor quality of life, intolerance of exercise, and diminished heart function. Researchers showed that, although typically associated with anemia, low iron levels negatively affect even a third of CHF patients who are not considered anemic. (Iron is important for growth, survival and a number of bodily processes. An excess of iron is as risky as a deficiency. Iron levels should be closely controlled because too much of this insoluble mineral can be toxic. However, deficiencies are considered to be relatively common.) Cardiologists, suggested the study team, should become aware of the possible importance of iron deficiency in heart patients. Correction of iron deficiency in CHF patients may lead to important clinical benefits. A key message of the study is that iron deficiency is often present without anemia. (Iron in meat is more easily absorbed than iron in vegetables but this mineral is also found in lentils, beans, poultry, fish, leafy vegetables, tofu, chickpeas, black-eyed peas, blackstrap molasses, fortified bread, and fortified breakfast cereals.) This study was presented September 5, 2010 at the European Society of Cardiology’s Congress 2010 in Stockholm.

KIDNEY PROBLEMS LINKED TO VITAMIN C DEFICIENCY 

A study has found that kidney dysfunction is associated with a low blood level of vitamin C. Also, low blood levels of vitamin C may cause damage, from greater oxidative stress, among kidney disease patients. It was noted that diabetic patients had consistently reduced levels of vitamin C. Lower blood levels of vitamin C have previously been linked to a greater risk of death from cardiovascular disease. People with higher levels of vitamin C have been found to have a reduced risk of cardiovascular disease and to have a greater life expectancy. (Vitamin C is an essential nutrient in humans and acts as an antioxidant, protecting the body against oxidative stress. Most species can synthesize vitamin C but humans cannot.) A brief summary of this study was released September 3 by the journal, Nephrology Dialysis Transplantation but the study will not be published in the print journal until a future issue. The full-text version is available online, for subscribers and those who pay the article access fee, at https://bit.ly/bPgeer

MORE BABIES SHOULD BE GIVEN IRON SUPPLEMENTS 

A study has shown that giving iron supplements to children with marginally low birth weights (2000-2500 grams) dramatically reduces the risk of developing iron deficiency and anemia, and as a result lowers the risk of poor brain and neurological development in infants. (Birth weight and infant nutrition are important risk factors for death risk in adulthood. Infants with low birth weight are at risk of developing nutrient deficiencies during their first year of life, including iron deficiency. Iron is necessary for the production of hemoglobin for the blood, and also for the development of the brain. Iron deficiency in infants has been shown to be associated with poor neurological development.) The study found no risks from the administration of iron drops to babies but also found that failure to give iron drops often resulted in anemia and iron deficiency. These findings could have a significant effect on nutritional recommendations for children with marginally low birth weights. The research was released September 6, 2010 and will be published in the October 2010 issue of the journal Pediatrics.

LOW LEVELS OF VITAMIN D LINKED TO DOUBLE THE RISK OF SCHIZOPHRENIA

Babies with low levels of vitamin D have an increased risk – in fact, double the risk – of developing schizophrenia later in life. That’s the conclusion of a new study of 424 individuals that showed a link between vitamin D (25 hydroxyvitamin D3) sufficiency and healthy brain growth. (Vitamin D is produced by the effect of sunshine on the skin and, although linked to bone health, researchers have previously found that people with schizophrenia are more likely to be born in winter, when sunlight is rare.) “Improving vitamin D levels in pregnant women and newborn babies could reduce the risk of later schizophrenia,” said one of the researchers. It’s important to note that a link between schizophrenia was found with both insufficient and excess levels of vitamin D. Further study is required to assess the actual best levels of vitamin D. The research team described this need for further study as “urgent.” This study was published September 7, 2010 in the Archives of General Psychiatry.

POOR DENTAL HYGIENE LINKED TO HEART DISEASE

A study suggests that without proper brushing of teeth and regular flossing, bacteria from plaque can escape into the bloodstream, where they can initiate blood clots and generally wreak havoc on the body. Researchers stressed that people need to maintain good dental hygiene to help ward off blood clots and heart disease in general. The study showed that, once let loose in the bloodstream, Streptococcus bacteria cause blood platelets to bind together and completely encase the bacteria, protecting the bacteria from both the body’s immune system and from antibacterial drugs. This same process creates small clots as well as growths on the heart valves or inflammation of the blood vessels. Dental health may prevent the release of bacteria into the blood and therefore, these other heart-related risks. The study was released September 9, 2010 at the autumn meeting of the Society for General Microbiology in Nottingham, UK.

VITAMIN B SUPPLEMENTS COULD HALT ALZHEIMER’S PROGRESSION

A study has found that supplementing the diet with large doses of vitamin B could cut, by a third to a half, the brain shrinkage that is common in elderly people with early signs of the disease and could slow, or even halt, the memory-robbing disease’s progression. The researchers stressed the need for further study to confirm these results but described the study outcome as “striking” and “dramatic.” Over a two-year period, half of the168 volunteers, all of whom were over the age of 70 and had been diagnosed with mild cognitive impairment (MCI), were given high daily doses of the B vitamins folate, B6 and B12. Specifically: “Participants were randomly assigned to two groups of equal size, one treated with folic acid (0.8 mg/d), vitamin B12 (0.5 mg/d) and vitamin B6 (20 mg/d), the other with placebo.” On average, compared to the group that received only placebo pills with no active ingredients, B-taking volunteers exhibited an average 30% lower degree of brain shrinkage, which is associated with atrophy; but in some cases, the reduced amount of atrophy was lower by as much as fifty percent. The study was released September 8, 2010 by the online journal Public Library of Science ONE and can be accessed free online at: https://bit.ly/btsJCl

DIET-INDUCED OBESITY ACCELERATES LEUKEMIA

A study has found that obesity resulting from diet accelerates – and theoretically, at least, may even trigger – the progression of acute lymphoblastic leukemia (ALL). Obesity has long been associated with an increased incidence of many cancers, including leukemia; but it has not been clear whether the higher risk was caused by obesity or by some other risk such as lifestyle or genetics. The researchers suggest that obesity may trigger leukemia and that “some hormone or factor in overweight individuals, perhaps produced by the fat tissue itself, may signal leukemia cells to grow and divide.” Not all obesity is caused by diet; weight gain can also be caused by genetics, aging, pregnancy, lack of sleep, some medicines and certain health conditions. This study is important due to the prevalence of obesity in society. Also, leukemia is the most common type of childhood cancer at a time when childhood obesity is at an all-time high. This just-released study will be published in the October 5 issue of the journal Cancer Prevention Research.

ANTIBIOTIC USE ALTERS INTESTINAL FLORA

A study has found that repeated use of antibiotics causes increasing and persistent changes in the composition of the gut’s beneficial bacteria colony. A previous study by the same scientist had shown that friendly bacteria in the gut bounce back fairly quickly after a single, short-term round of Cipro, an antibiotic often used for intestinal, urinary and systemic infections. But this longer study found that as few as two rounds of Cipro, six months apart, is sufficient to produce subtle long term effects such as the replacement of an entire species of bacteria with a closely related species; or the complete elimination of some species. The problem with this subtle effect is that an eradicated bacteria species may have been performing an important function such as fighting a particular pathogen with the toxin it produces; with those particular bacteria missing, the pathogen could multiply unchecked until, years later, it has invaded the patient’s system.

The second administration of antibiotics appeared to have a greater impact than the first, although the effect varied between test subjects. This study was released September 13 and will appear in a future issue of the journal Proceedings of the National Academy of Sciences.

WATERCRESS MAY “TURN OFF” BREAST CANCER

A study has found that a compound in watercress may have the power to suppress breast cancer cell development. Normally, as cancer cells develop they send out signals that cause new blood vessels to grow into the tumour and these nourish the rapidly growing cancer cells with oxygen and nutrients. But a watercress compound (called phenylethyl isothiocyanate) appears to turn off the tumour signal within the body, effectively starving the breast cancer cells. The amount of watercress consumed by test subjects was 80gm, which is about a cereal bowl full. (This leaf vegetable is known for its tangy, peppery flavour and is a member of the Brassica or cruciferous family, which includes cabbage and broccoli. Previously, watercress has been linked to a lower risk of lung cancer and of low thyroid levels.) The study leader suggested more research is needed on the relation between what we eat and cancer. This study was presented at a September 14, 2010 press conference and will be published in the current issue of the British Journal of Nutrition.

ANXIETY MEDICATIONS RAISE MORTALITY RISK

A 12-year study of 14,000 patients has found that those who take medications to treat insomnia and anxiety, even on an irregular schedule, have a 36% greater risk of dying than those who do not. This is considered a small but significant increase in risk.
What causes this higher risk of mortality among those taking drugs to treat insomnia and anxiety is not clear, but researchers pointed out that these prescriptions affect reaction time, alertness and coordination, making patients subject to falls and accidents. Also, patients on these meds are more prone to breathing problems during sleep; and some drugs of this type increase the risk of suicidal behaviours.
The team leader suggested that non-drug cognitive behavioral therapies have been shown to be effective against both insomnia and anxiety and that this type of therapy should be suggested to patients. Also, according to the head researcher, “These medications aren’t candy, and taking them is far from harmless.” This study was published in the September 2010 issue of the Canadian Journal of Psychiatry.

POOR DIET AND INADEQUATE EXERCISE MAY UNDERLIE CHILDHOOD ASTHMA

A study of 18,000 children aged four to 12 suggests that unbalanced nutrition and lack of exercise may be the major risk factors for developing childhood asthma, even in those of a healthy weight. These findings challenge the long-held idea that obesity itself is a risk factor for asthma. Instead, despite the fact that obese individuals showed a greater risk of asthma, the study implicated these patients’ metabolic dysfunction in the risk of asthma, such as triglyceride levels and glucose metabolism – and not their obesity itself. The conditions known as dyslipidemia (high triglyceride levels) and hyperinsulinemia (acanthosis nigricans or AN) are very common in both obesity and metabolic syndrome, and as a result, suggests the study, obesity has been linked with asthma risk when in fact these conditions themselves are the most likely risk factor.
Metabolic factors, suggests the study, may be the actual cause of the airway inflammation and hyper-reactivity that leads to asthma. In fact, it is the childhood experience of poor nutrition and lack of exercise that may lead to later asthma, according to the research. This study was released September 16, 2010 and will be published in a future issue of the American Journal of Respiratory and Critical Care Medicine.

OMEGA-3 FATTY ACIDS IN FISH OILS FIGHT INFLAMMATION AND DIABETES 

Finally, a study has identified the mechanism by which omega-3 fatty acids appear to effectively fight chronic inflammation, insulin resistance and diabetes. The study found that there is a key receptor in obese body fat, and that omega-3 oils – specifically docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) – activate this receptor, which results in broad anti-inflammatory effects and improved systemic insulin sensitivity. (There is a strong connection between obesity and diabetes.) The effect of fish oil was powerful, according to the researchers, and, “The omega-3 fatty acids switch on the receptor, killing the inflammatory response.”
The study team warned that more study is required to determine how much fish oil constitutes a safe and effective dose. Researchers suggested that the study could eventually lead to a natural dietary remedy for the more than 23 million Americans who suffer from diabetes. This study was published in the September 3 issue of the journal, Cell. The full-text version is now available online without fee at https://bit.ly/9TQ09d

SPECIAL DIET PREVENTS KIDNEY STONES

A study has found that the DASH diet, a diet designed to combat high blood pressure (also known as Dietary Approaches to Stop Hyper-tension), also helps prevent kidney stones. This diet is high in fruits, vegetables, nuts and legumes, dairy products, and whole grains, and low in sweetened beverages and red and processed meats. Despite similar fluid intakes, the study observed a greater output of urine among those on the DASH diet, which may stem partly from the fact that DASH foods have higher water content. More important, DASH subjects’ urine held higher concentrations of citrate, an important inhibitor of calcium kidney stones.
Researchers suggested that two foods prominent in the DASH diet have potent kidney stone-fighting properties: low-fat dairy products and plant foods. This just-released study will be published in the October 2010 issue of the Clinical Journal of the American Society of Nephrology.

(Editor’s note: Although the benefits of dairy have been mentioned a few times this month in News Briefs, for those with dairy intolerance there are many equally beneficial vegetarian alternatives to dairy products.)

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