Tuesday, March 30, 2010

Radon Causes Deaths from Lung Cancer

In Germany, radon in residential buildings has been shown to be a major risk factor for lung cancer. It's clear that this is a worldwide health concern.

A research paper in the current edition of Deutsches Ă„rzteblatt International by Klaus Schmid of the University of Erlangen-Nuremberg and his coauthors discusses the 1900 deaths from lung cancer that they see every year in Germany, purely due to radon within residential buildings.

The authors base their assessment on the results of relevant German studies which include the recently published guidelines of the German Society for Occupational and Environmental Medicine as well as a current publication from the German Commission on Radiological Protection. These indicate that radon within residential buildings makes a major contribution to the radiological exposure of the general population. Schmid and his colleagues refer to measurements taken from residential areas -- those found mildly unhealthy levels of radon in 36% of homes and severely unhealthy levels in more than another 18%.

Exposure within houses is predominantly due to release of radon-containing subsurface air from the soil into the building. Radon can penetrate into houses through leaks in the foundation or in the walls that are in contact with the soil.

Occupational physicians have long known that radon can cause lung cancer, particularly in uranium miners. For individuals without occupational exposure, radon is regarded as the second most important cause of lung cancer after smoking.


Thursday, March 25, 2010

Arginine Supplementation Found to Improve Cycling Performance

Researchers writing in BioMed Central’s Journal of the International Society of Sports Nutrition tested a combination of the amino acid Arginine and an antioxidant in sixteen cyclists, finding that it enhanced their anaerobic threshold. (This term refers to the amount of work done before lactic acid begins to accumulate in the blood.)

Researcher Zhaoping Li worked with a team of scientists from the University of California (Los Angeles) to carry out the randomized controlled trial with older cyclists. She said, “The loss of exercise capacity with age often results in a reduction in physical fitness and more rapid senescence. A dietary supplement that increases exercise capacity might help to preserve physical fitness by optimizing performance and improving general health and well being in older people."

One way in which older people may find their exercised capacity reduced revolves around the signaling molecule nitric oxide (NO), which is involved in many physiological processes, including those related to working out. NO production diminishes in quantity and availability as we age and is associated with an increased prevalence of other cardiovascular risk factors. In the body, NO is created from the amino acid arginine and is inactivated by oxygen free radicals. By supplementing the diet with both this precursor and an anti-oxidant, the researchers hoped to support the NO system in the cyclists and thereby enhance performance.

Sixteen cyclists aged between 50 and 73 were randomly assigned to receive either the supplement or dummy placebo pills. After one week of study, the anaerobic threshold of the supplement group increased, while that of the control group did not significantly alter. This increase in anaerobic threshold was preserved at week three. According to Li, “We’ve demonstrated a 16.7% increase in anaerobic threshold. This indicates a potential role of arginine and antioxidant supplementation in improving exercise performance in elderly."


Wednesday, March 24, 2010

Endometriosis Risk Lower with Omega 3 Food Intake

Women whose diets are rich in foods containing Omega-3 oils appear to be less likely to develop endometriosis, while those whose diets are heavily laden with trans fats might be more likely to develop the debilitating condition, new research suggests. The study, one of the largest to have investigated the links between diet and endometriosis, was published today (Wednesday 24 March) in the journal of Human Reproduction.

The study found that while the total amount of fat in the diet did not matter, the type of fat did indeed make a difference. Women who ate the highest amount of long-chain Omega-3 fatty acids were 22% less likely to be diagnosed with endometriosis than those who ate the least; those who ate the most trans fats had a 48% increased risk, compared with those who ate the least.

These findings, resulting from 70,709 American nurses who were followed for 12 years, suggest that diet may be important in the development of endometriosis. They also provide more evidence that a low fat diet is not necessarily the healthiest. Another impact from the research is further evidence for the case that eliminating trans fats from the food supply is a very good thing.

The study’s leader, Dr. Stacey Missmer, is an assistant professor of obstetrics, gynaecology and reproductive biology at Brigham and Women's Hospital and Harvard Medical School in Boston.

“Millions of women worldwide suffer from endometriosis. Many women have been searching for something they can actually do for themselves, or their daughters, to reduce the risk of developing the disease, and these findings suggest that dietary changes may be something they can do. The results need to be confirmed by further research, but this study gives us a strong indication that we’re on the right track in identifying food rich in Omega-3 oils as protective for endometriosis and trans fats as detrimental,” Dr. Missmer added.

Endometriosis occurs when pieces of the womb lining, or endometrium, is found outside the womb. This tissue behaves in the same way as it does in the womb – growing during the menstrual cycle in response to oestrogen in anticipation of an egg being fertilized and shedding as blood when there’s no pregnancy. However, when it grows outside the womb, it is trapped and cannot leave the body as menstruation. Some women experience no symptoms, but for many it is very incapacitating, causing severe pain. The tissue can also stick to other organs, sometimes leading to infertility. It afflicts about 10% of women. The cause is poorly understood and there is no cure. Symptoms are traditionally treated with pain medication, hormone drugs or surgery.

It's nice to hear another Omega 3 success story. Long-chain Omega-3 fatty acids are found mostly in oily fish. They have been linked to reduced heart disease risk. Trans fats are artificially produced through hydrogenation, which turns liquid vegetable oil into solid fat. Used in thousands of processed foods, from snacks to ready-meals, they have already been linked to increased heart disease risk. We read frequently about various communities around the world that have instituted bans on these dangerous fats.


Wednesday, March 17, 2010

Compound in Bananas Looks to have Great Anti-HIV Abilties

A strong possibility exists that new therapeutics directed against HIV may come from research on bananas, proving once again that the plant world holds enormous potential for cures. This potent new inhibitor of HIV, derived from bananas, may open the door to new treatments to prevent sexual transmission of HIV, according to a University of Michigan Medical School study published March 19 in the Journal of Biological Chemistry.

Scientists have an emerging interest in lectins, naturally occurring chemicals in plants, because of their ability to halt the chain of reaction that leads to a variety of infections.In laboratory tests, BanLec (the lectin found in bananas) was clearly as potent as two anti-HIV drugs currently on the market. Based on these findings, BanLec may become a less expensive new component of applied vaginal microbicides, researchers say.

This banana extract could become one of the ways of stopping the spread of the HIV, which is a category of drug that is vitally needed. The rate of new infections of HIV is outpacing the rate of new individuals getting anti-retroviral drugs by 2.5 to1, and at present it appears an effective vaccine is years away. That's why bananas could step in and save the day.

Study senior author David Marvovitz, M.D., professor of internal medicine at the U-M Medical School, says that while condom use is quite effective, condoms are most successful in preventing infection if used consistently and correctly, which is often not the case, particularly in developing countries.

“[Some] women have little control over sexual encounters so development of a long-lasting, self-applied microbicide is very attractive,” Markovitz says. The most promising compounds for inhibiting vaginal and rectal HIV transmission are agents that block the virus prior to integration into its target cell, which is what this lectin appears to do.

Lectins are sugar-binding proteins. They can identify foreign invaders, like a virus, in the body, and attach themselves to the pathogen. The U-M team discovered that BanLec can inhibit HIV infection by binding to the sugar-rich HIV-1 envelope protein, gp120, and block its entry to the body. It's exciting because therapies using BanLec could be cheaper to create than current anti-retroviral medications which use synthetically produced components, plus BanLec may provide a wider range of protection, researchers say.


Stressful Pregnancy May Lead to Asthma Later in Life

New research proves how stress during pregnancy may raise the risk of asthma in children. Researchers at Brigham and Women’s Hospital and Harvard Medical School in Boston have investigated differences in immune function markers in cord blood between infants born to mothers in high stress environments and nfants born to mothers with lower stress. They have found marked differences in patterns that may be associated with asthma risk later in life.

“This is the first study in humans to show that increased stress experienced during pregnancy in these urban, largely minority women, is associated with different patterns of cord blood cytokine production to various environmental stimuli, relative to babies born to lower-stressed mothers,” said Rosalind Wright, M.D., M.P.H., associate physician at Brigham and Women’s Hospital.

The findings have been published online in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine. Asthma is known to be more prevalent among ethnic minorities and among disadvantaged urban communities, but the disparity is not completely explained by known physical factors. Urban women living in the inner-city also experience significant stress, particularly minority women. This research may finally be shedding some light on why this difference has occurred.

The role of stress in asthma development is poorly understood, but animal studies have suggested that the mother’s stress during pregnancy can influence the offspring’s immune system, starting in the womb.


Tuesday, March 9, 2010

Checklist for Depressive Symptoms

I just found a one-page, 27-item questionnaire that is available free online. It was designed for doctors to help them screen their patients, but It's really an interesting tool for anyone who wants to know if they are showing symptoms of the four most common psychiatric illnesses. It's validity has been confirmed in a study led by University of North Carolina at Chapel Hill researchers.

"Results of the My Mood Monitor (M-3) Checklist" was published in the March/April 2010 issue of Annals of Family Medicine. The checklist was developed by M-3 Information of Bethesda, Md., and is available at www.mymoodmonitor.com (click on the headline of this blog post for the link). I took this test and found it very easy and informative. Obviously, if you have any issues it's going to direct you to your doctor, but it is possible to learn about how you are feeling and whether or not these feelings are "normal."

The lead author of the report says that about one in 10 Americans who suffer from depression and anxiety-related mental health disorders never receives treatment because they don’t understand what’s wrong, and when they go to their family doctor these treatable illnesses are too often missed.


Monday, March 8, 2010

Women Who Drink Moderately are Less Likely to Gain Weight

According to a new report in the March 8th issue of the Archives of Internal Medicine, normal-weight women who drink a light-to-moderate amount of alcohol appear to gain less weight and have a lower risk of becoming overweight and obese than non-drinkers.

Alcohol contains about 7 calories per gram, and there are approximately 28 grams per ounce -- so it is possible to see that alcohol drinking could indeed contribute to weight gain. However, research has not provided evidence that consuming alcohol is a risk factor for obesity. In fact, studies like this one suggest that a moderate consumption of alcohol can actually have the opposite effect.

Dr. Lu Wang of Brigham and Women’s Hospital (Boston) and colleagues studied more than 19,000 U.S. women age 39 or older with normal weight. On an initial questionnaire, participants reported how many alcoholic beverages they typically drank per day. A total of 7,346 reported drinking no alcohol; 6,312 drank less than 5 grams; 3,865 drank 5 to less than 15 grams; 1,129 drank 15 to less than 30 grams; and 568 drank 30 grams per day or more.

Over an average of 13 years of follow-up, women on average gained weight progressively. Women who did not drink alcohol at all gained the most weight, with weight gain decreasing as alcohol intake increased. A total of 7,942 (41.3 percent) women who initially had normal weight become overweight or obese, including 732 who become obese. Compared with women who did not drink at all, those who consumed some but less than 40 grams per day of alcohol were less likely to become overweight or obese. Women who drank 15 to less than 30 grams per day had the lowest risk, which was almost 30 percent lower than that of non-drinkers.

“An inverse association between alcohol intake and risk of becoming overweight or obese was noted for all four types of alcoholic beverages [red wine, white wine, beer and liquor], with the strongest association found for red wine and a weak yet significant association for white wine after multivariate adjustment,” the authors write.

The authors caution that, given potential medical and psychosocial problems related to drinking alcohol, its beneficial and adverse effects for each individual must be considered before making any recommendation about its use. It's interesting to note the red wine connection here once again.