Saturday, August 24, 2013

How You Can Help Fight Superbugs


“As soon as antibiotics were discovered and developed for medical use, bacteria began the Darwinian ‘arms race’ that has been fought ever since.”  So wrote Steve Heilig in the most recent Journal of the San Francisco Medical Society, where he is a director. Due to overuse of antibiotics, “antimicrobial resistance has reached a crisis stage in human medicine.”  You are doubtless aware that doctors should not prescribe antibiotics for viral infections (colds and flu) unless there is good evidence of an additional bacterial infection.  You may not know that 70 to 80 percent of all antibiotics produced by U.S. companies are used in farm animals.  These animals are often penned in crowded, dirty conditions; they are fed low doses of antibiotics to prevent infections and promote growth.  Bacteria are killed by the low doses used, but some develop mutations that make them immune to the drugs.  These bacteria are passed on to the farmers, their contacts, and the consumer.  Thorough cooking can destroy them, but beware of cutting boards, knives, your hands, and ‘rare’ burgers. 

In a 1976 study, small amounts of tetracycline were given to a flock of chickens by a researcher.  He found that the chickens began to carry bacteria resistant to tetracycline and other antibiotics.  So did the farmers who tended them.  Based on this kind of evidence, in 1977 the FDA announced plans to ban the feeding of low doses of antibiotics to livestock.  However, there was strong backpressure from legislators and agribusiness, and the FDA failed to act on its own recommendation.  The American Academy of Pediatrics, the Centers for Disease Control, the National Academy of Sciences, and the World Health Organization had identified subtherapeutic use of antibiotics as a human health issue.  More than 30 years later, in 2011, the FDA reacted when sued by the Natural Resources Defense Council and other groups.  It revoked its 1977 recommendation (never implemented) and said a ‘voluntary effort’ would be more effective.  There is no evidence that this has worked.  Currently there are over 90,000 deaths per year due to antibiotic resistance.  The Centers for Disease Control are alarmed.  We all should be.

You may have heard of a dreaded bacterium called MRSA – methicillin resistant Staphylococcus aureus, which is found in the community as well as in hospitals.  MRSA related deaths in the U.S. have risen to over 19,000 per year. from antibiotic resistant bacteria.  In Iowa, large pig farms where 2000 pigs are confined shoulder to shoulder, nearly half of these animals carry MRSA according to a 2009 study.  Almost half the workers there carry MRSA as well.

Here’s news close to home – an Iowa pig farmer who used routine antibiotics joined Niman Ranch’s pork collective; he stopped confining his animals and using antibiotics. He found he had the same results as Danish farmers who banned subtherapeutic antibiotics in 2000.  Pork production rose, and the incidence of resistant bacteria fell dramatically in people and animals. 

What can we do to protect ourselves, our children and the public?  There is a microbiologist in Congress, Louise Slaughter, a Democrat from New York.  Every year she introduces a bill called The Preservation of Antibiotics for Medical Treatment Act. We should make sure our congressman, Jared Huffman, supports this bill.  We should refuse to buy or eat meat, poultry, eggs or fish treated with antibiotics.  If it is labeled organic, this is a given. Otherwise, ask the butcher behind the counter. Trader Joe’s shoppers answered a poll by Consumer Union; 69% wanted the store to stop selling meat raised on antibiotics.  The store has hedged on this; although they do sell some antibiotic-free meats, they “do not presume to make choices” for their customers. Bring up this issue when you shop there. Whole Foods does not sell antibiotic-raised meats.  While these personal choices can make the meat you buy more expensive, eating less of it, and using it as a condiment/flavoring for vegetables is a wise move.  When you eat out, ask about the source of the meat, be sure it is not too rare, or go vegetarian.  There is no conclusive proof as yet that taking a daily probiotic pill, or eating yogurt with live cultures is helpful, but some studies point in that direction.  I think it’s a good idea. 
Sadja Greenwood, MD   back issues at

Sunday, August 11, 2013

Go to Health: Exercise 2013

New research on exercise is reported in the August issue of Scientific American. You probably know that the ‘runner’s high’ (also felt after vigorous dancing, biking, and many sports) is caused by the brain’s release of endorphins (opioid-like hormones that evoke pleasurable feeling). Recently, research has also shown that exercise increases our ability to concentrate, think and make decisions. Exercise increases the size of a part of the brain called the hippocampus. The specific part of the hippocampus affected by exercise is one that allows people to remember familiar surroundings. Animal studies have shown that exercise increases the level of chemicals responsible for triggering the growth of new neurons. A molecule known as brain-derived neurotrophic factor is responsible. Newborn neurons are thought to help with distinguishing between similar but different events and things. Think about this – go for a hike; create new brain cells!

New research on how exercise prevents heart disease goes beyond the lowering of blood pressure, lowering LDL cholesterol (the ‘bad’ kind) and raising HDL choesterol (the ‘good’ kind). The more important LDL related effect is that exercise increases the number of larger, safer, LDL particles and decreases the number of small, dangerous ones. A couch potato might have an identical cholesterol level as an active person, but be more at risk for heart attack because of the predominance of small LDL molecules.

Exercise is a key to keeping blood sugar normal. As you use your muscles, they need increasing amounts of glucose to fuel their efforts. The liver sends out more glucose and the pancreas releases insulin - to signal cells to draw glucose from the blood. As exercise becomes a daily habit, muscles grow more sensitive to the effects of insulin, so lower levels will accomplish the same result, and the pancreas does not have to work as hard to keep glucose levels normal. This is particularly helpful for people with type 2 diabetes, whose bodies have often become resistant to insulin. Recent studies show that combining aerobic exercise (like brisk walking) with resistance training (weights, leg presses, et al) is the best for keeping blood glucose normal.

We know that we should be exercising, but many Americans fail to achieve the recommended half an hour of moderate activity for five or more days a week. However, a recent analysis of six studies, totaling 655,000 adults tracked for about 10 years, found that people doing leisurely activities like washing the car or taking a stroll for 11 minutes a day had a 1.8-year longer life expectancy after age 40 than inactive people. Those who met the guidelines for moderate activity gained 3.4 years of life, and those who were active between 60 and 90 minutes a day had greater gains – 4.2 years. It seems that we evolved as creatures who moved – think about walking out of Africa to populate the rest of the world. If you find it hard to begin, get a dog. Then you’ll have to walk, and she’ll always love you.

Sadja Greenwood past issues at

Go To Health: Human Papilloma Virus and Its Consequences

Cervical cancer, detected by regular Pap smears before it becomes serious, is caused by a sexually transmitted virus. Nuns and lesbians don’t get cervical cancer if they never have intercourse with men. Condoms offer some protection. Were you ever told this when you (or your partner) went for a Pap test? These facts were ignored for years by the medical profession and popular culture – perhaps because of the discomfort people feel about discussing the nitty-gritty of sex, perhaps because of ignorance. The papilloma virus (HPV) that causes cervical cancer can also cause cancers of the vagina, vulva, penis, anus and throat. Cervical cancer is the most common of these problems, but the number of throat cancers from HPV are now on the rise. The actor Michael Douglas made headlines recently when he told a British newspaper that his throat cancer had come from performing oral sex.

Cancers of the base of the tongue, tonsils and walls of the pharynx are becoming more common. A decade ago, people with head and neck cancers were smokers or heavy drinkers. Now only 20% are smokers or drinkers, and the other 80% have cancers caused by an HPV infection. This year an estimated 14,000 people in the US will be diagnosed with head and neck cancers; most of them will be between 40 and 50 years old, and 3 out of 4 will be men, according to Dr. Robert Haddad of the Dana Farber Cancer Institute. Haddad talks about ‘an epidemic’ of HPV–related head and neck cancers. If oral sex is a factor, the predominance of men may be because vaginal fluid has more virus than the surface of the penis.

There are two vaccines available against HPV infection – Gardisil and Cervarix. These vaccines protect against many of the some 100 strains of HPV, including the high risk strains HPV-16 and 18 which are a known cause of cervical, throat, anal and vaginal cancers. A study supported by the National Cancer Institute has just been published which showed that sexually active young women in Costa Rica had 93% protection against infection with HPV types 16 and 18, after receiving immunization with Cervarix.. Although the study did not include men, it is believed that they would get the same protection with this vaccine.

The Gardisil vaccine was approved by the FDA and the CDC (Centers for Disease Control) for girls ages 9-26 in 2009, and for boys in 2011. Cervarix has also received FDA approval, and may be even more effective. The vaccine is given by 3 injections over 6-12 months. There has been controversy about these vaccines because of reports of serious reactions after injection, but careful studies by the CDC do not show that these reports are valid. Most side effects consist of pain, redness, and swelling at the injection site, and occasional fainting, fatigue, headache, muscle pain, gastrointestinal symptoms, and joint pain.

Women are advised to continue having Pap tests for cervical cancer even after vaccination, as the vaccines are not effective against all strains of HPV. Men and women should know they should not ignore difficulty swallowing or feeling/seeing a lump in the throat or on a tonsil. Seek medical attention promptly if this occurs. Sexually active people should also be aware of many other types of sexually transmitted disease, including HIV/AIDS, syphilis, gonorrhea (rapidly becoming drug resistant), Chlamydia, Herpes et al. Condoms are very helpful but not foolproof for prevention. The birth control pill and IUD are highly effective against pregnancy but do nothing to prevent STDs.. Have you ever wondered why sex scenes in movies and television never involve a discussion of these potential problems? Is it still that controversial? We have calorie counts on some menus, and dire (small print) warning on cigarettes. But nothing is said about sex. Young women in college are initiating hook-ups without emotional involvement so they won’t get derailed from their independent careers. The recent NYTimes article (7/12/13) about this did not mention STDs or birth control. Go figure.

Sadja Greenwood, MD, MPH -->