Sunday, August 31, 2014

Organic Foods Contain More Antioxidants

Back in 2012, a comprehensive meta-analysis of many previous studies concluded that in terms of nutrition, organic foods are generally no better for you than non-organic foods (this blog Sept. 6, 2012). Of course, that didn’t sit too well with supporters of the organic food movement. Well finally, proponents of organic foods have something to talk about, too. Another comprehensive meta-analysis, this one by primarily European researchers, concludes that organic foods have fewer pesticides and more antioxidants than non-organic foods.

The finding of fewer pesticides is to be expected, of course, since the pesticides they’re talking about aren’t supposed to be used on organically grown crops in the first place. The same was found in the previous nutritional study. The finding that organic foods contain more antioxidants will be welcomed by supporters of organic foods. As you may know, antioxidants are thought to be protective against cell damage, and hence could (in theory) assist in delaying cellular aging and possibly reducing the risk of cancer.

Unfortunately, “in theory” does not always coincide with “in reality”. Neither group of authors is claiming that eating organic foods actually leads to better health, because at the moment there is no evidence to support such a claim. If its better health we want, we should concentrate on eating more fruits and vegetables of either kind (organic or non-organic) according to our preference, and less refined sugar and fat.

Saturday, August 23, 2014

Illegal Human Organ Trafficking

It is illegal to sell or buy human organs in most countries. It is also against the principles of the Transplant Society and the International Society of Nephrology, whose joint Declaration of Istanbul states that organ trafficking and transplant tourism “ violate the principle of equity, justice, and respect for human dignity and should be prohibited.”

But where there’s money to be made, someone will try to make it. As the gap between the demand for kidneys and their supply (from cadavers or live donors) continues to widen, unscrupulous underground “businessmen” manage to bring desperate patients and willing sellers together, for money. If you can find one of these kidney brokers, the going price seems to be nearly $200,000 to buy a kidney, but less than $20,000 to sell one.

Kidney brokers are rarely caught and convicted, in part because they may not live on the same continent as the buyer and seller. So where exactly is the crime committed? Furthermore, brokers claim to enlist only altruistic donors who are not paid. They tell the potential buyer that the high price is to “cover expenses”. Donors are paid under the table and then coached to say that they are not doing it for money. No one really believes that, however, when the donor is from Costa Rica and the patient (a total stranger) is from Israel or the U.S. Desperate buyers are willing to turn a blind eye to the truth when their life is at stake. For a peek into this shadowy world, see the New York Times article on the subject or visit the Declaration of Istanbul website highlighted above.

Reasonable people have argued that the only way to eliminate the black market in human organs is to permit the buying and selling of organs, subject to controls to protect potential donors. They argue that thousands of lives could be saved every year. Whether buying/selling organs could be done without undue coercion of the poor is still an open question. At least one study in this country suggests that perhaps it could (this blog, April 26, 2010.) I’m not convinced, however, that the same results would hold in places where people are truly desperate, and not just below the average U.S. income. I’m reserving judgment on this idea for now.

Wednesday, August 20, 2014

Why Societies Collapse

Why have some of the greatest human societies of all time essentially collapsed to insignificance, or at least undergone steep declines? What fate awaits today’s most important societies, or even the human race as a whole? Is collapse inevitable?

A study to be published in Ecological Economics offers some interesting observations on these questions, based on a mathematical modeling analysis of past societies. According to the authors of the paper, two commonly-observed events associated with societal collapse or steep decline are; 1) resource over-use beyond carrying capacity, and 2) social stratification (increased separation into rich versus poor). The first factor should be obvious to any student of biology: Any population, whether it be bacteria or humans, must ultimately undergo a decline in population or at least a decline in living standards if it depletes the resources available to it. That concept is at the heart of the philosophy that ultimately humans must learn to live within a “sustainable world” if we are to stay healthy, happy, and successful.

The second factor, social stratification, is not so obvious. The authors propose several ways that increased separation between rich and poor could affect a society. One might be that the rich over-utilize resources, leaving too few resources for the poor. Another could be that as the poor make it into the rich category, there are too few workers left to do a society’s work.

Press reports of the study have made it sound as if we’re doomed. But nothing about the study implies that at all. There’s no reason why an enlightened society couldn’t make an effort to minimize social stratification and learn to use its resources wisely. Forewarned is forearmed.

Friday, August 15, 2014

First Antibiotic-Resistant Bacteria; Now Herbicide-Resistant Weeds

Nearly all of the corn and soybeans planted in this country have been genetically modified to make them resistant to a common herbicide called Roundup (glyphosate). Such genetically modified organisms (GMOs) can be sprayed with Roundup during the growing season to kill weeds without harming the crop.

Given what we know about how the over-use of antibiotics has led to the appearance of antibiotic-resistant strains of bacteria, what did we think would happen when we began spraying GMO crops heavily with a single herbicide? Why, of course - Roundup-resistant weeds! According to a recent New York Times article, an invasive Roundup-resistant weed called palmer amaranth (carelessweed) is already sweeping northward from the south, wreaking havoc on farmers’ fields.

Monsanto, the manufacturer of Roundup and the developer of the GMO seeds most farmers now plant, is planning even more genetic modification of corn and soybeans to make them resistant to other herbicides as well, allowing farmers to spray more than one herbicide on their crops. Each new modification will buy farmers some time in the perpetual battle against weeds (and also enrich Monsanto). But it’s not hard to see that in the long run this is a losing game; the over-use of any herbicide will ultimately lead to the emergence of herbicide-resistant weeds. Adaptation and evolution are hallmarks of the natural world. Farmers will have to develop other approaches (in addition to just spraying herbicides) to combat weeds effectively.

Saturday, August 9, 2014

Two Experimental Drugs Used to Treat Ebola

Desperate times call for desperate measures.

Two drugs are currently being used to treat patients with Ebola hemorrhagic fever (Ebola). Both are relatively untested, meaning they are a long way from being formally approved by the FDA. But when the choice is between watching patients die or trying something, it seems that trying something wins out.

The use of untested drugs and/or drugs in very short supply raises all kinds of ethical issues, of course. The first drug, called ZMapp, had never been tried on humans before now. It was first used on the two Americans who contracted the disease in Liberia and who have since been flown to Atlanta. Aside from the issue of risk to the two patients, there’s the troubling ethical question of favoritism; why was it given to the two Americans first, and not to any of the many African patients? (On the other hand, had it been given first to Africans, there would be complaints that Africans were being used as guinea pigs. You can’t win this one!). 

The second drug, called TKM-Ebola, was already in the human testing phase when the Ebola epidemic began. But the tests, which were being conducted on normal human volunteers, had been halted temporarily because of side effects in one volunteer. Given the current situation, though, the FDA took the unprecedented step of approving TKM-Ebola for Ebola patients anyway. Apparently the FDA felt that the potential benefits to patients who actually had Ebola far outweighed the risks.

It takes time to ramp up the production of any drug. Both drugs will be in short supply in the near future, which means that choosing which patients will get them will remain an issue for a while. From a medical point of view, it’ll be interesting to see how effective they actually are.

Tuesday, August 5, 2014

An Ebola Outbreak in West Africa

A recent outbreak of a viral disease called Ebola hemorrhagic fever (Ebola HF) has killed over 700 people in the West African nations of Guinea, Liberia, and Sierra Leone.   Infected persons initially exhibit symptoms including a fever, fatigue, and joint, muscle and abdominal pain, similar to the flu.  But unlike the flu, Ebola HF interferes with mechanisms involved in blood clotting, ultimately leading to hemorrhage in multiple organs.  Over 55% of all persons infected with Ebola HF have died, making Ebola HF one of the most deadly viral diseases currently infecting humans.

Before you get too worried, you should know that the virus that causes Ebola HF is NOT transmitted through the air (like the common cold) or even by casual physical contact (e.g. a handshake).  It is transmitted primarily through direct contact with bodily fluids.  Persons most at risk are people who live with an infected person, health care workers, and persons who work with infected cadavers, such as funeral workers.  The availability of good medical care (not always available in West Africa) reduces the death rate significantly.  So far, two Americans have contracted the disease while working in Liberia; both have been transported to the U.S. and are being treated in a special medical unit at Emory University in Atlanta.  Both are expected to recover.

The CDC will be sending 50 additional disease experts to the region within the next month in an effort to contain the outbreak.  For updates and more information about Ebola HF, see the CDC’s website page on the topic.

Is there anything you should be doing right now to protect yourself?  Well, yes… according to the CDC you should “avoid nonessential travel to the west African nations of Guinea, Liberia, and Sierra Leone”.  Shouldn’t be too hard for most of us.

Friday, August 1, 2014

Synthetic Human Growth Hormone Use by Teens

An increasing number of teens are using synthetic human growth hormone (HGH) to enhance their appearance and/or their athletic performance, according to the latest survey from the Partnership for Drug-Free Kids.  Eleven percent of teens now say that they have used HGH at least once, up from 5% just a year ago.   Girls are nearly as likely to use HGH as boys.   Teens’ attitudes are changing, too; fewer teens report that there is a moderate or great risk associated with performance-enhancing drugs than in past years.  The full survey on teens’ attitudes toward HGH and other performance-enhancing steroids, as well as marijuana and prescription medicines, can be accessed here.

Whether HGH actually does enhance teens’ appearance or athletic performance is still an open question.  WebMD calls the effects of HGH on athletic performance “unknown”.   Nor is it known whether there are any long-term negative effects of HGH use on health.  And finally, there are no guarantees that HGH products sold illegally over the Internet actually contain HGH, as advertised.

The U.S. Food and Drug Administration (FDA), the agency responsible for regulating medical drugs, has approved HGH for use by prescription only, for specific medical conditions.  It does not have the resources to prevent Internet sales of HGH, any more than the police are able to stop illicit prescription drug or marijuana use.  Teens are taking a risk by buying HCG over the internet, without a prescription.

For more on this subject, go to a previous blog post titled "Athlete Caught Doping with Growth Hormone."