Wednesday, October 31, 2012

HPV – Who Knew All it Could Do?


HPV – the Human Papilloma Virus – has been known for years to be the main cause of cervical cancer in women. There are over 40 types of HPV that are transmitted by direct skin to skin contact during vaginal, anal and oral sex, and most do not cause disease.  However, infection with certain viral types,  mainly but not exclusively  HPV 16 and 18, can cause cervical cancer if not treated. This is why the Pap test is so important for women who are or have been sexually active, with men or with women.  The Pap test is a procedure in which cells are scraped from the cervix and looked at under a microscope. The Pap test can detect abnormal cells before they become cancerous, and early treatment in the doctor’s office can get rid of the problem. However, some women don’t know about the need for regular pelvic exams, or can’t afford them. There were 4,200 deaths from cervical cancer in the US last year.  Cervical cancer is a very serious problem in developing countries which cannot afford to do Pap screening. 

Some subtypes of HPV can also cause cancers of the vulva, penis, anus and the mouth and throat.  Sexually transmitted HPV type 16 causes about 85% of anal cancers according to the National Cancer Institute. The risk for anal cancer is much higher in gay and bisexual men than heterosexual men.  Women who have anal sex are also at greater risk.

Condoms, which help to prevent pregnancy and HIVAIDS, can prevent HPV infection by about 70% if used every time.  Skin to skin transmission can still occur outside of the condom.  Still  - condom use is important with new partners.   The good news is that most HPV infections are cleared by the immune system in a few years and never cause a problem.  However, some people don’t clear the virus, and their infections remain. 

In recent years there has been an increase of cancers of the throat and base of the tongue, caused by HPV 16.  Previously known risk factors for throat cancer included smoking and alcohol, but throat cancers are now seen in younger people who don’t smoke or abuse alcohol. Throat cancers from HPV are more commonly seen in men, but women are also affected.  Oral sex is considered to be a major predisposing factor.  The increase in throat cancer is considered serious, because it can be hard to detect early.

Since most people do have genital and oral sex, how can we view this threat and deal with it?  Prevention and early detection are vitally important.  This would include:
*consistent condom use with new partners, even with oral sex.  This may seem unlikely, especially for teenagers trying to do the right thing to avoid pregnancy.  However, they should be informed about the problem.
*Make sure your children get the HPV vaccine, Gardasil or Cervarix – given in 3 shots over 6 months.  Both are effective in preventing infections that cause cervical cancer.  Gardasil is believed to prevent more HPV types, those that cause cancer of the anus, vulva and vagina.  HPV vaccination is recommended by the Centers for Disease Control for 11 and 12 year old girls, and girls and women age 13 through 26 who have not been vaccinated.  Gardasil has been found to be safe and effective for males age 9-26.  Vaccinating a boy with Gardasil will help his partners, and also help him to prevent oral cancer.  The cost of the vaccine is about $130 per dose - $390 for the series.  Most health insurance plans cover the cost, and the Vaccines for Children program may be able to help.
*Pap tests are still important for women, even if vaccinated, because the vaccines do not prevent about 30% of HPV types that can cause cervical cancer.
*Being in a faithful relationship with one partner, limiting the number of sex partners, and choosing a partner with few prior sex partners can be helpful.   However, it is not always possible to know if a partner or oneself is currently infected with HPV. 
*Early detection of cervical, vaginal, vulvar and anal cancer can be done by regular medical examinations, self exams, and alertness to anything that feels like a persistent sore or abnormal growth. 
*Early detection of cancers of the mouth and throat can be done by regular visits to the dentist and dental hygienist, who should look for abnormalities in the mouth and throat, including hidden areas at the back of the tongue.   Everyone should be aware of symptoms such as a persistent sore throat or mouth sore, a feeling of a mass in the throat, a lump in the neck, or difficulty swallowing.  
Check it out!
* Keep your immune system strong by getting enough sleep, exercising moderately, eating healthy food (lots of vegetables!), and avoiding tobacco, dangerous drugs, and excess alcohol.

Our venerable sage Ben Franklin told us:  An ounce of prevention is worth a pound of cure.  Let’s follow his advice. 

Sadja Greenwood, M.D., MPH  back issues on this blog

Monday, October 15, 2012

Arsenic in Rice?

Arsenic is a chemical element found in water, soil and air. For this reason, it is inevitably found in some foods. Human activities have added arsenic to the environment, through burning coal, oil, gasoline and wood, and through the use of arsenic compounds in pesticides, herbicides and wood preservatives. The Food and Drug Administration (FDA) monitors foods in our diet; it has analyzed arsenic levels in rice for 20 years, and has not found evidence of change in arsenic levels. However, researchers are now better able to measure whether existing levels represent more or less toxic forms of the element. It plans to complete its analysis of about 1,200 rice products (rice milk, rice cakes, infant cereal, etc) by the end of the year, and to issue guidelines.

Meanwhile, Consumer Reports, published by Consumers Union, has stated that its tests of more than 60 samples of rice and rice products found inorganic arsenic, a probable human carcinogen, in most samples. Earlier this year, they had found worrisome levels of arsenic in apple and grape juices, and called on the FDA to set limits for arsenic in these juices. They are now asking the FDA to set limits for arsenic in rice.

Consumer Reports’ study found:
*White rice grown in Arkansas, Missouri, Louisiana and Texas had higher arsenic levels than samples from California, India, and Thailand.
*Brown rice had higher levels than white rice, comparing rice from within a tested brand.
*Infant rice cereals and drink products contained worrisome levels of arsenic.
*Groups who rely on rice as a staple, such as some Asians and Hispanics, were found to have higher arsenic levels.

Rice grown in Texas, Louisiana and other gulf coast states have high levels of arsenic because of cotton growing in times past. Arsenic pesticides were used to control the boll weevil. California rice, and Asian rice have considerably lower levels.

Consumer Reports advises that children under 5 not be given rice drinks daily. Similar advice has been given in the United Kingdom.

Consumer Reports has asked the FDA to ban the feeding of arsenic containing drugs to animals (used for growth promotion and disease prevention). The manure of these animals contains arsenic, which can be used to fertilize food crops. It also asked for a phase out of arsenic containing pesticides.

Philip Landrigan, an epidemiologist, author and pediatrician at New York’s Mt. Sinai School of Medicine, suggests that pregnant women and babies avoid rice, or use only small amounts of California rice, or switch to other grains, such as oats or barley.

Arsenic has been implicated as a cause of skin cancer (non-melanoma), and is also related to cancers of the liver, lung, kidney and bladder. The evidence for this comes from studies in Taiwan, where well water contains high amounts of arsenic. The same is true in Bangladesh – tube wells drilled to protect the population from bacterial diarrheal disease have been found to have high levels of arsenic. This is a very serious situation in parts of India as well. Current remedial efforts include digging very deep wells, where water may have lower arsenic levels.

What can you do about arsenic in food and water? There is virtually no arsenic in Bolinas water. Call your local water department to find levels if you live elsewhere. Avoid apple and grape juice unless it is organic – even then, it’s better to eat the whole fruit. Avoid chicken, unless it is organic. Eat California rice, but don’t make it your everyday staple. Try almond milk if you usually drink rice milk. If you are avoiding gluten, try millet as a rice substitute. Millet should be rinsed first, and cooks in 20 minutes. You can make it very tasty by cooking it with onions, garlic, chopped nuts, and spices. When cooking, I always think of chef Rebecca Katz’ suggestion: FASS. F stands for a bit of fat, such as olive oil. A stands for acid – meaning a little something sour, like a squeeze of lemon. S stands for sweet – a drop of maple syrup, or pomegranate juice, or some frozen corn. S stands for salty – a pinch of salt. Put this in every dish, and you’ll love the result!

Sadja Greenwood, MD, MPH see more on this blog

Saturday, October 6, 2012

What Are the Benefits of Organic Food?

A recent study from Stanford University looked at 17 studies comparing people who ate organic or conventional diets, and 223 studies comparing the bacterial, fungal or pesticide contamination of such foods. There were no long-term studies of health outcomes between the two diets in their analysis. The studies showed no consistent differences in the vitamin content of organic products, although there were higher levels of omega-3 fatty acids in organic milk. The study did find that organic produce had a 30% lower risk of pesticide contamination, but the pesticide levels in all food generally fell within the allowable safety limits. They found that children on organic diets had lower levels of pesticide residues in their urine, and organic chicken and pork reduced exposure to antibiotic resistant bacteria, but the clinical significance of all these findings were found to be unclear.

Many people have been confused by these findings from Stanford. Is organic food worth the extra money? Charles Benbrook, a professor at Washington State University’s Center for Sustaining Agriculture and Natural Resources, wrote a compelling answer in the October issue of Nutrition Action Healthletter. Benbrook has worked for the National Academy of Sciences, and consults for The Organic Center. He says that 60% of studies do show a higher nutrient content in organic foods, especially when the comparison is between fruits and vegetable grown in similar locations. The Stanford study did not consistently make such comparisons.

A recent study of tomatoes in Spain showed that organic tomatoes had twice the antioxidant levels as conventional tomatoes. There are two reasons for this. Organic plants have to fend off a range of insects, so they develop more defensive compounds that also keep us healthy. Conventional crops are produced with large amounts of nitrogen fertilizer, which drives up yields and fruit or leaf size, but dilutes the levels of vitamins, minerals and antioxidants.

Contaminants that cause food poisoning can grow more readily in conventional fields, because of extra nitrogen, and the lesser microbial diversity due to pesticide use. In organic fields there is more microbial biodiversity, so pathogens may not last as long or become as numerous.

Organic foods may not be pesticide free, because of traces blown in from conventional fields. However, pesticide levels are markedly lower. Benbrook has devised a scoring system, the Dietary Risk Index (DRI) that measures the number of different pesticide residues and their levels. Looking at organic versus conventional strawberries, blueberries, apples, grapes, nectarines, peaches and pears grown in the US, the DRI was 3 for organics, versus 24 for conventional fruits. Imported conventional fruits from Chile and Argentina have much higher DRIs than those grown in the US, because of more stringent regulations of pesticide use in the US.

According to Professor Benbrook, there is compelling evidence that low level exposure to organophosphate insecticides in food are contributing to neurologic and developmental problems in children, such as lowered IQ. Lead exposure was found to be most harmful in a Harvard study, followed by organophosphate pesticides and methylmercury. The most compelling evidence of harm comes from the insecticide chlorpyrifos, which has been banned by the EPA for home use, but is still permitted in agriculture. Its level in pregnant farmworkers correlated with lower IQs in their children. When researchers at Emory University in Atlanta gave children organic fruits and vegetables, chlorpyrifos levels fell to almost undetectable levels in their urine in 5 days. Chlorpyrifos is made by Dow Chemical. A coalition of farmworker and advocacy groups filed a lawsuit against the EPA in 2007 seeking to ban the use of chlorpyrifos; the suit is still pending.

Professor Benbrook thinks that the most important dietary change we can make is to eat more fruits and vegetables, and less bad fat, added sugar and processed food. I’m going to add – eat with the seasons, so that you avoid imported produce with its higher levels of pesticides. The second most important is – of course - to eat organic produce and organic grains. If you can afford it, this is your most important step.

Subscribe to the Nutrition Action Healthletter if you want to keep up with the science of nutrition in an easy, readable format. It’s easy to find the address on-line, and 10 issues cost only $10!

Finally – let always give thanks to our local organic farmers, and to the Bolinas People’s store with its daily array of luscious, healthy food!

Sadja Greenwood MD back issues at on this blog