HEALTHY SCIENCE
Microwaved Socks, and Other Tales from the Airwaves
I look forward to my Friday mornings. Thatâs when I spend an hour and a half conversing with the public on CJAD Radio in Montreal. The idea behind the show is for me to provide reliable scientific information, answer questions about current concerns, and attempt to clear up some of the mysteries that permeate daily life. But the show is an education for me, as well. For over twenty years, it has allowed me to monitor the pulse of the population and gain a glimpse into its psyche. I have been pleased by callers who have made unusual scientific observations, elated by those with intriguing questions, and frustrated by the occasional demonstration of scientific illiteracy. I have also come to realize that people are burdened with numerous fears, both rational and irrational. And I have learned not to be surprised. Shocked, maybe â but never surprised.
âHow do you wash microwaves out of socks?â one caller queried. I didnât quite know what to make of this. Quickly, though, we established that he was not worried about having trodden on some stray microwaves, but he had heard about a device being marketed to reduce the risks of cell phone use. First of all, we need to understand that there is very little scientific evidence to suggest that cell phones are dangerous, other than to those who use them while driving. But that has not stopped the inventive marketers. Theyâve come up with a socklike device that one places over the phone to absorb the âharmful microwaves.â The instructions that come along with this gem apparently instruct the user to launder the sock regularly to âwash out the radiation.â Total nonsense.
Microwaves are a form of energy, and they can indeed be absorbed by materials. After all, thatâs how microwave ovens work. Moisture absorbs the waves, energizing the water molecules. They move around more rapidly, and it is this motion that we sense as heat. But microwaves cannot be stored in a substance for later release. It seems, though, that this contention is not restricted to scam artists who want to protect us from cell phones. A listener once called to ask how long one should allow microwaved food to stand after cooking to âallow the microwaves to escape.â Obviously, this person had been reading her microwave cookbook, which would have advised her to allow microwaved food to stand briefly before serving it. This is common practice, necessary to complete the cooking process. Contrary to what many think, microwaves do not penetrate food deeply. The exterior of the food in question is easily heated, but the inside cooks through heat transfer by conduction. Thatâs why the food must stand for a few minutes. It has nothing to do with allowing vagrant microwaves to escape.
Microwaves are not the only form of radiation causing undue concern. A terribly agitated caller was worried because after being x-rayed she was asked to take the films to her physician herself. She had heard all about exposure to x-rays being dangerous and thought that by carrying the films she was âexposingâ herself.
Since the infamous date of 9/11, a number of people have asked about wearing clothes that have gone through x-ray scanners at airports. They are concerned that these items may become radioactive and pose a risk to their health. Excessive exposure to x-rays can certainly be risky, but x-rayed items do not store and reemit radiation. Unfortunately, just a mention of the word radiation is often enough to alarm people.
A gentleman wanted to know what the safest way was to dispose of a broken compact-disc player. I didnât realize what he was getting at until he asked whether a laser was a form of radiation, which of course it is. Radiation is nothing more than the propagation of energy through space. Turn on a light and you are exposed to radiation. The caller knew that CD players use a laser, and since lasers produce radiation, there had to be some risk. The laser beam in a CD player is just a special type of light beam that poses no danger at all, and it is only emitted when the device is on. So old CD players can be safely discarded. But old laminated pictures may be a different story.
I had to address this issue when a caller asked if it was safe to burn a laminated picture in her fireplace. It turned out that she had been recently divorced and wanted no reminders of her former spouse. Burning his picture seemed appropriate, but she had heard that laminated photos were mounted on particleboard glued together with urea-formaldehyde resin. She was worried that the heat would release formaldehyde, which she had heard was toxic. Indeed, formaldehyde is a problematic substance, but the amount released in this particular combustion process would be too little to cause concern. Still, I suggested that if she was still worried, she could hang on to the picture until the next hazardous waste collection took place in her municipality. She liked that idea â she told me that âhazardous wasteâ was an excellent description of her former mate.
Then there was the listener who wanted to know if lighting a match was a good way to get rid of the smell of natural gas in a house. That question prompted me to launch into a lecture on a common misunderstanding about gas. Natural gas, I said, is just methane, and methane has no smell. Thatâs why odiferous compounds are added to make sure that gas leaks are readily detected. I explained that soot from a burning match could absorb small amounts of smelly compounds, but, I added somewhat smugly, it was not a good idea to go around striking matches in a house that could be filled with methane. It was then that the caller sheepishly informed me he knew all that, but the ânatural gasâ he was talking about was more likely to be found in the bathroom than in the kitchen. It was I, not he, who had jumped to the wrong conclusion. Like I said, my Friday mornings are interesting.
Yes, Scientists Are Allowed to Change Their Minds
âGee! You scientists â one day you say this, the next day you say that,â exclaimed the apparently frustrated lady as she approached me after a public lecture. âI remember having you as a prof twenty years ago, and you maintained that anyone who had a balanced diet did not have to worry about taking vitamin supplements. Now here you are suggesting that we take a multivitamin and that there may be value in some other supplements as well. Canât you guys make up your minds?â
Well, frankly, no. At least not completely. Science rarely gives us conclusive answers. It is an ongoing process that attempts to remain in step with the latest research. Thatâs why changes in recommendations made to the public should come as no surprise. Indeed, I think I would be more concerned if I were saying the same things today as I did twenty years ago, because it would indicate that we had made no progress in our understanding of nutrition. Also, I would suggest that a time span of twenty years is not exactly âone day this, the next day that.â During this period, for example, we have firmly established the role of the B vitamins in preventing the buildup of homocysteine in the blood, and we have recognized the potential value of an increased intake of vitamin D. In general, we have come to understand more fully that some vitamins may do more than just prevent nutritional deficiency diseases. At worst, as Iâve often said, a multivitamin may just make for more expensive urine. At best, it may result in significant health benefits.
Thatâs the argument I was giving to my former student when another gentleman joined the discussion. He took issue with what he perceived to be my enthusiasm for vitamin supplements (although I hardly think that suggesting a multivitamin qualifies me as a supplement pusher) and informed me that he had just given up his vitamin E pills because he did not want to âdie of a heart attack.â I was a little taken aback by this, because vitamin E has been associated with protection against heart disease. So what was this guy talking about? He had âproofâ of the dangers of vitamin E, he said, and he proceeded to pull a neatly folded newspaper article out of his pocket. âVitamin E Debunked as Heart Healthy,â the headline screamed.
Now it all began to click. A study published in The New England Journal of Medicine had garnered a great deal of media attention because it suggested that taking a mixture of antioxidants reduced the effectiveness of a cholesterol-lowering medication. It was an interesting study, to be sure, but it certainly did not show that vitamin E supplements are dangerous, as many newspaper accounts inferred.
One of the most commonly prescribed classes of drugs for reducing LDL cholesterol, the so-called âbad cholesterol,â is the statins. LDL causes deposits to form in arteries and triggers heart attacks. This happens when the cholesterol that has been deposited undergoes a chemical reaction and becomes oxidized cholesterol, the most dangerous form. By contrast, HDL, or high density lipoprotein, scavenges cholesterol from the blood and prevents its deposition. Thatâs why it is referred to as âgood cholesterol.â HDL can be increased by taking high doses of niacin, one of the B vitamins. There is also some evidence that antioxidants such as vitamin C, vitamin E, beta-carotene, and selenium can reduce the oxidation of LDL and therefore reduce the risk of heart disease. A logical question to ask, therefore, is what would happen if someone at risk for heart disease took a statin drug, plus niacin, plus antioxidants? Would the beneficial effects be combined and the risk reduced accordingly?
This is just what researchers at the National Institutes of Health decided to find out. So they enrolled 160 subjects with existing heart disease in a study. Forty patients were given Zocor â one of the most popular of the statin drugs â together with niacin, while forty others took the same drugs plus vitamins C, E, beta-carotene, and selenium. Another group of forty took only the antioxidants, and a fourth group was given a placebo. The results were surprising. As expected, Zocor and niacin reduced LDL, raised HDL, and lowered the risk of heart attack. But when researchers incorporated the antioxidants into the mix, they noted a smaller increase in HDL and a slight increase in artery blockages. The groups taking only the antioxidants or a placebo had the most cardiac complications.
What are we to make of this? The basic conclusion is that the mix of antioxidants blunted the benefits of the combined statin-niacin therapy. We donât know which antioxidant was responsible. Vitamin E may not even have played a role at all. And this study doesnât give us information about what happens when only a statin is taken together with antioxidants, a situation that is far more common than combined statin-niacin therapy. Finally, we must remember that all the participants in this trial already had heart disease, so we can draw no conclusions at all about the possible effectiveness of antioxidants in preventing the disease in the first place. Certainly, the data do not justify headlines about antioxidants increasing the risk of heart disease.
Really, the only appropriate conclusion we can draw from this study is that anyone who has been prescribed both a statin and niacin is probably better off not taking any antioxidants. But there is absolutely nothing in the study to suggest that antioxidants, and vitamin E in particular, are dangerous to the general population. Any contention about vitamin E causing heart attacks is totally unjustified. True, the study does hint that the benefits of antioxidant supplements have probably been overstated. Weâll see. No one can be certain about what further research will show. But of one thing, I am sure. If Iâm around in twenty years to talk about this stuff, I wonât be saying the same things as Iâm saying now. Thatâs the way science works. And do I have a better chance of being around if I take antioxidants? I guess that depends on which study I read.
Iâll Take the Yogurt, but Hold the Enema Machine
It was an experience I never thought I would have. I had read about it, I had seen pictures of it. Now here I was, sitting in Dr. John Harvey Kelloggâs patented vibrating chair, happily vvvibrrraaatinggg away. I was visiting the little museum in Battle Creek, Michigan, dedicated to the exploits of the good doctor, whose flaky ideas about health had captured Americaâs imagination in the late 1800s.
Kellogg was infatuated with the human colon. He believed that virtually all ailments could be traced to âautointoxicationâ through substances produced by the âputrefyingâ bacteria inhabiting the colon. The key to health, he maintained, is a clean colon. His cereal flakes served as âlittle internal broomsâ that helped sweep out the colonâs contents, especially if these were loosened by the activity of the vibrating chair. I didnât note any such effect. Neither did I notice any stimulation of the internal organs after galloping on Dr. Kelloggâs famous mechanical horse. But I did spy something while riding that horse. A curious glass and metal device sat unceremoniously in a corner, barely eliciting a glance from other museum visitors. I recognized it right away. It was Kelloggâs enema machine.
Dr. John Harvey Kellogg administered and received more enemas than anyone in history. His electric enema appliance pumped fifteen gallons of water through the colon in just one minute. But that was not the end of the cleansing process. Next came the yogurt flush. Made with the amicable bacterium Lactobacillus bulgaricus, the yogurt would âdrive out the disease-forming bacteria that had been implanted by the putrefactive action of flesh foods.â âBalance your intestinal flora,â Kellogg maintained, âand youâll live as long as the rugged mountain men of Bulgaria!â And, according to Elie Metchnikoff, the Russian bacteriologist whose research triggered Kelloggâs yogurt compulsion, that was pretty long.
Metchnikoff had caused quite a sensation with his theory that the longevity of Bulgarians was due to the copious amounts of yogurt they ate. He even had a theory to explain how this happened. The good bugs, which Metchnikoff named in honor of the Bulgarians, overwhelmed the bad bugs in the gut that caused disease. Yogurt was elevated to the rank of a wonder food, in spite of the fact that Metchnikoff had no real evidence for his theory, or indeed for his notion that Bulgarians experienced remarkable longevity.
Metchnikoff was awarded a Nobel Prize in 1908 (for work unrelated to yogurt), and that helped enshrine the yogurt mystique and make the food a âhealthâ staple in the Balkans and in Russia. Indeed, when the former Soviet Union began its manned space flight program, it established a microbiology laboratory at the Baikonur Cosmodrome to study the cosmonautsâ gut bacteria. The concern was that the stresses of space travel might change the balance of these bacteria and cause some nasty symptoms. A spacecraft is certainly no place to be struck by diarrhea!
The researchers experimented with giving the cosmonauts yogurt before their missions. They must have been satisfied with the results, because the practice became routine, as did the collection of bacteria samples from the spacemenâs saliva and guts after they returned to Earth. The researchers cultured these samples and used them to make yogurt with the hope that, having withstood the stresses of space travel, these bacteria would create a healthier product. They probably didnât, but they did help the struggling Russian space program raise funds. A commercial variety of yogurt made with bacteria cultured from cosmonaut emissions is still being touted as a health food.
While the appeal of yogurt cultured from cosmonaut poop may be limited, the notion of introducing beneficial bacteria into the gut is receiving widespread attention from scientists. Research into âprobioticsâ is mushrooming. Simply put, a probiotic is any preparation that contains specific microorganisms in sufficient numbers to alter the microbial flora in a host and exert beneficial health effects. There is increasing evidence that yogurt, if made with the right bacteria, falls into this category. Traditionally, yogurt has been made with Lactobacillus bulgaricus and Streptococcus thermophilus, which are acid sensitive and do not make it through the stomach to the colon in sufficient numbers. But acidophilus and bifido bacteria do. And they really do squeeze out disease-causing bacteria, such as Clostridium difficile, often responsible for diarrhea.
Very good scientific evidence now exists for treating diarrhea with probiotics, including the type associated with antibiotic use. Antibiotics can destroy some of the gutâs beneficial bacteria, the kind that keep troublesome microbes in check. Clostridium difficile can seize the opportunity, multiply, and cause severe diarrhea. In rare cases, such diarrhea resists all treatments. Well, maybe not all. Dr. Lawrence Brandt, a gastroenterologist at Montefiore Medical Center in New York, has come up with a novel, though admittedly unconventional, approach. In one highly publicized case, he mixed stool samples from a patientâs husband in saline water and deposited little chunks of this matter every ten centimeters along the womanâs colon. This âfecal colonoscopyâ resulted in the almost immediate resolution of symptoms, in all likelihood due to the restoration of a healthy balance of microflora in the gut. Doesnât sound particularly appealing, but protracted diarrhea is no pleasure either. Science sometimes moves forward in unusual ways.
In children, diarrhea is most often caused by a rotavirus infection. Studies have shown that treatment with an oral hydration solution containing Lactobacillus GG significantly shortens the duration of the problem. Yet that may be just the starting point for probiotic benefits. There is tantalizing evidence for cancer prevention and immune system enhancement. Some probiotics can destroy cancer-causing agents in the gut, and at least one excellent study has shown that the risk of eczema in babies can be reduced if they are given Lactobacillus GG. Chances are that this will work for some allergies as well. Particularly noteworthy is the fact that in over 150 studies of probiotics, no adverse effects have been noted.
Now the vexing question is to determine which probiotic bacteria are the most beneficial. Lactobacillus GG (modestly named by its discoverers, Sherwood Gorbach and Barry Goldin) looks very promising. It performs well against diarrhea, shows anticancer effects in animals, and in some ...