TERRY GROSS, host:
This is FRESH AIR. I'm Terry Gross.
One experience that most of us share and dread is the scratchy sore throat that signals the arrival of a cold. Our guest, science writer Jennifer Ackerman, says colds send us to the doctor's office 100 million times a year, and we still haven't figured them out.
In her new book, she explains the latest science about the common cold and looks at what tests show about the effectiveness of various cold remedies. Prepare for disappointment on that subject.
Jennifer Ackerman is the author of two previous books and has written for National Geographic, the New York Times, Scientific American and other publications. Her new book is called "Ah-Choo! The Uncommon Life of Your Common Cold." She spoke to FRESH AIR contributor Dave Davies.
DAVE DAVIES, host:
Well, Jennifer Ackerman, welcome to FRESH AIR. As it happens, I am in the third day of a cold myself, just fortuitously. But I noticed that some colds are longer and nastier than others, and I learned from your book they really aren't one disease, are they?
Ms. JENNIFER ACKERMAN (Author, "Ah-Choo! The Uncommon Life of Your Common Cold"): No. There are close to 200 viruses, probably more, that cause the common cold.
The most common is the rhinovirus. And here we are in September, when there's actually a peak of colds from the rhinovirus. That peak begins about 17 days after school starts, when kids are swapping germs in the classroom and then bringing them home to the family and from there to the workplace.
DAVIES: All right, so let's talk about the experience of getting a cold. Why does the misery start in our throats?
Ms. ACKERMAN: Well, this is where the receptors are that the viruses like to latch onto to do their dirty work. And so, this is that sort of scratchy-throat feeling that you get when you're coming down with a cold. That's the genesis, is these viruses latching on to your cells and your throat.
And then what happens is the body responds to the presence of the virus by generating inflammatory agents that inflame the body cells and tissues, giving us that runny nose and the cough.
This is a really interesting point, actually, because it's a relatively new insight in the world of cold science. People thought that the miseries of the cold were really the upshot of the destructive effect of the virus itself on our cells.
This is true of flu viruses. The flu bugs destroy the cells of our lower respiratory tract. But it turns out that the common cold viruses don't really do any direct damage to our cells, that cold symptoms result from the body's response to the intruders.
DAVIES: So it's the immune system kicking into gear that makes us uncomfortable, right?
Ms. ACKERMAN: That's right. The body makes this whole slew of inflammatory agents and our cells and tissues get all upset and give us these, the runny nose and sneezing and all the symptoms of a cold.
DAVIES: Now, I thought we would talk about how we get colds or avoid getting them. And you have a lovely description in your book of a time when you were in a checkout counter at a grocery store and noticed that you were in the line of a checker who appeared to be suffering from a cold. If you could just read that little section for us.
Ms. ACKERMAN: I'd love to.
(Reading) It was a few days before Christmas, and I was in a hurry. I considered swooping my piles back into the cart and hightailing it to the next line over, but it was too late: She was ringing up my milk and cheese.
She looked miserable and sniffed noisily every 10 seconds or so as she plowed slowly through my pile of organic onions, potatoes and peppers. Still, her affliction seemed harmless enough until, with just a few items left in my order, she suddenly wrinkled her nose, caught her breath, turned slightly and sneezed ferociously, sending a spray of fine droplets partly into her sleeve but mostly onto my heaping grocery bag.
Then she paused to tear off a piece of paper towel and blew her nose into it with such audible force that I feared for the integrity of her sinuses.
To her credit, she did take a second to spritz with hand sanitizer before reaching for my head of broccoli. However, a minute later, she wiped her nose with the back of her hand, then picked up my eco-friendly bag and handed it over the counter to me, tucking into it, I feared, a bonus load of rhinoviruses.
(Soundbite of laughter)
DAVIES: That's our guest, Jennifer Ackerman, reading from her book "Ah-Choo! The Uncommon Life of Your Common Cold."
Well, I have to ask you: Did you get sick from that little encounter?
Ms. ACKERMAN: No, I didn't. I actually ran right home and washed my hands, and no, I didn't get sick from that encounter.
DAVIES: Well, let's talk about how we get colds and don't get them. I guess you certainly want to be around not - you want to avoid being around people who are sneezing or coughing, right?
Ms. ACKERMAN: That's right. Some cold viruses are carried in airborne droplets from coughs and sneezes, but the most common cause of the common cold, the rhinovirus, it's most commonly spread by direct contact with objects that are -or hands contaminated by the nasal secretions, you know, from someone who's infected.
So the virus is transmitted when you touch your hand to a contaminated object like a bus rail or a politician's hand and then you touch your own hand to your nose or eyes. This is the way the virus travels most frequently.
DAVIES: So, compulsively washing your hands is a good idea year-round?
Ms. ACKERMAN: Yes. Now, I don't advocate, you know, being Lady Macbeth about this. I really adhere to what one of the scientists I spoke with called prudent paranoia, which is, you know, you pay attention. You know, if you shake hands with somebody who's obviously ill and, you know, you do want to wash your hands, just as I did with the cashier at the grocery store.
The other great technique is not touching your face. And this is actually, you know, easier said than done. Just try not touching your face for a day. I mean, try being conscious of it. Most of us touch our faces about one to three times every five minutes. So that's, like, you know, 200 to 600 times a day.
We also pick our noses about five times an hour, and these are...
DAVIES: Oh, seriously, really?
(Soundbite of laughter)
Ms. ACKERMAN: Studies suggest this. These are really hard habits to beat. So when people ask me, you know, what do I do to avoid the cold this season? I say start practicing now not touching your nose or face or your eyes.
DAVIES: All right. Now, you wrote about a study that looked at places that might carry germs and the extent to which you'd find them there. Doctor's office, lot of germs. Daycare, lot of germs. What about elevators?
Ms. ACKERMAN: Yes, well, you know, we all touch elevator buttons. There are, I would say, cold hot spots that are commonly touched by people. In the office, it's often the, you know, the Xerox machine or the refrigerator handle in the kitchen, the microwave handle in the kitchen.
Yes, these are places where you just don't know who's been there before you. And they are a vehicle for transmission.
DAVIES: Okay, airplanes, hotels, beware as well, right?
Ms. ACKERMAN: Yes, indeed. The studies of what people leave behind in hotels, apart from their spare change and bobby pins and that sort of thing, was really disheartening. The scientists discovered that cold viruses are often, you know, left on TV remotes, pencils, door handles, places that are frequently not really cleaned by the cleaning crew.
So, you know, you enter a hotel room, and somebody who has been there, you know, a few hours or even 24 hours before may very well have had a cold and left you a little welcoming gift.
DAVIES: All right. Let's talk about ways that we can try and avoid them. You know, one thing people always debate is whether you can catch a cold from standing out in the rain or being in cold weather.
Ms. ACKERMAN: Yes, that is absolutely a myth. Colds are caused not by cold but by viruses. And so, exposure to cold really has nothing to do with catching cold, nor does your susceptibility increase if you're cold. Really solid scientific studies on this are pretty solid that there's no greater risk. So, you know, going outside and catching a chill is really not going to increase your chances of catching cold.
DAVIES: And the reason we see them more in certain seasons than others is because kids get to school and spread them, and then I guess...
Ms. ACKERMAN: That's right.
DAVIES: Right, and the viruses do like some kinds of weather more than others, don't they?
Ms. ACKERMAN: Yes. The reason that cold viruses are more common in fall and winter is because the colder, wetter weather drives us indoors where the viruses leap much more readily from nose to nose.
DAVIES: Are you more likely to get a cold if you're exhausted, sleep-deprived?
Ms. ACKERMAN: Yes. Now, there are two different things here. Fatigue, just being worn down, doesn't necessarily increase your susceptibility. Two things, however, do.
Sleep deprivation, if you get less than seven hours of sleep, that increases your risk of getting a cold. Very interesting study recently that found that people who sleep less than seven hours a night are really much more likely to get colds than longer sleepers.
The other risk factor is chronic stress. When we are under continuous stress, we are more susceptible to getting a cold.
DAVIES: We're speaking with Jennifer Ackerman. Her new book about the common cold is called "Ah-Choo!" We'll talk more after a break. This is FRESH AIR.
(Soundbite of music)
DAVIES: If you're just joining us, we're speaking with science writer Jennifer Ackerman. She's written a new book called "Ah-Choo! The Uncommon Life of Your Common Cold."
So let's talk about remedies and cures. Vitamin C, for years and years, people have sworn by it, both to ward off colds and to fight its symptoms when infected. Anything to it?
Ms. ACKERMAN: Well, unfortunately, you know, Vitamin C has been the subject of study for years and years and years. And the bottom line is that when it comes to preventing the common cold in the general population, Vitamin C gets a grade of about D.
If it's taken on a regular basis, it really doesn't help to prevent colds in the general population. If you take daily Vitamin C, it may reduce the severity of symptoms but only very slightly. It has this ability to dry nasal secretions a little bit. So there is some positive effect when you have a cold. It can actually shorten the duration of a cold just a tiny fraction.
There is some preventive benefit for people who are engaged in endurance exercise or people who are exposed to extreme cold. The studies suggest that for these people, these sort of - in these extreme environments or doing this extreme exercise, a daily dose of about 200 milligrams actually reduces the incidence of colds by half.
DAVIES: So if you're a marathon runner or work on an ice-breaker, maybe, huh?
Ms. ACKERMAN: Yes.
DAVIES: Another remedy that's arisen in recent years and until I read your book was one of my favorites was zinc lozenges. They say take them quickly, and it'll knock the symptoms down. Anything to it?
Ms. ACKERMAN: Well, I share your disappointment. Zinc lozenges were favorites in my family for years and years. When my, you know, kids were little and they had a scratchy throat, I'd, you know, give them a lemon-flavored zinc lozenge to suck. And I was just sure I was doing the right thing as a mom.
But it turns out that studies suggest that the mineral is touted as this way of reducing the severity of symptoms and shortening a cold, but as it happens, the only really consistent effect reported by the high-quality studies is this very bitter, medicinal aftertaste in the mouth.
And moreover, with zinc, we have to be a little bit concerned about the zinc nasal sprays and gels, which have been shown to cause permanent damage to the sense of smell in some people.
DAVIES: All right, now another product that was hot for a while was a tablet that you dissolve in water called Airborne, right? What do the tests show about that?
Ms. ACKERMAN: Yeah, Airborne is the number one natural cold remedy. I think it has sales of something like $150 million a year. And, you know, it was billed as this homey product invented by a schoolteacher, this, you know, fizzy concoction of vitamins, minerals and herbs. And the ads claimed that, you know, all you had to do was take it before you entered a germy environment, and you'd instantly be protected. And if you were already down with a cold, the ads said, you know, it was clinically proven to nip colds in the bud.
Well, baloney on both counts. It does no such thing. The watchdog groups who look at these products and test them have really called it just an overpriced vitamin pill that's been really cleverly but deceptively marketed.
If there's any effect of Airborne, it's due to a really high dose of Vitamin C, which we've discussed, you know, has some effects of drying secretions and shortening colds slightly. But it's far, far cheaper to just buy the vitamin than to buy this, you know, overpriced, multivitamin product.
DAVIES: Okay, what about echinacea? People talk about that as being helpful.
Ms. ACKERMAN: Yeah, echinacea has also been widely used and, you know, I certainly gave it to my kids, too. And I think it's, in terms of popularity for cold sufferers, it's still the sort of king of herbal remedies.
But there's pretty solid evidence that it doesn't work. It won't protect you from catching a cold and it does very little to relieve symptoms once you have one. And another point to make here, a lot of these echinacea compounds actually contain very little of the herb at all.
So if you've had success with echinacea, and you believe in your, its ability to heal you, whether it's from the placebo effect or actually from the herb, just beware of the product that you're buying and make sure that it actually contains the herb.
DAVIES: Is there anything out there that really helps to either avoid colds or reduce their severity or duration? Chicken soup?
(Soundbite of laughter)
Ms. ACKERMAN: Well, chicken soup is interesting. You know, it's been touted as a cold remedy by grandmothers, including my own, for, I don't know, the past thousand years or so. And as it turns out, you know, there may be some medicinal value to chicken soup but not in the way you might think.
There was a lung specialist from the University of Nebraska whose wife made this wonderful chicken soup with vegetables for her big family every time they got a cold. And he thought, well, I'm going to put the broth to the test and see whether it actually has any biological effect.
And he did find that in the Petri dish that the chicken soup had some anti-inflammatory action. So again, we know the cold symptoms are caused by inflammation. And the chicken soup seemed to, in a Petri dish anyway, have some anti-inflammatory effects.
Now, it's never been tested in humans this way. In theory, it may actually ease symptoms. But I actually think that it's the warm broth and the love that goes into making it that makes it healing.
You know, there are some studies that suggest that empathy can actually cut short a cold by a full day. So if you think that somebody is really empathizing with your misery and makes you this wonderful pot of chicken soup, you know, that's better than any drug on the market, and there aren't any side effects.
DAVIES: All right, so if we can't cure the colds, and we can't avoid them, maybe we can treat the symptoms. Let's talk about what you do when you have this affliction. First of all, there are a lot of multi-symptom cold medicines. Are they a good idea?
Generally, experts say no. Multi-symptom cold medications include a mix of ingredients, some of which may be useful and some not, depending on what your most severe symptoms are.
And also, they often contain a pretty substantial dose of pain reliever, you know, for instance, acetaminophen. And if you take that multi-symptom cold medication not sort of understanding that it has this big dose of acetaminophen, which is, you know, the active agreement in Tylenol and other products, and you take a Tylenol or some other acetaminophen-containing pill, you can actually risk overdose, and that can put your liver in trouble.
DAVIES: So you can treat individual symptoms. And you hear sometimes people say, well, you know, the symptoms are there for a reason. That's your body fighting the infection. And if you treat the symptoms, you might actually be prolonging the duration of the cold. Is that true?
Ms. ACKERMAN: Not from what I understand from the experts. The advice that I heed is advocated by Jack Gwaltney, who studied the common cold for 40 years, and he's arguably one of the world's foremost experts.
And what he recommends is taking two single-ingredient drugs every 12 hours. And you start at the earliest sign of a cold, that sort of scratchy throat, and you continue until your symptoms are clear.
And the two drugs that he suggests taking are, first, a non-steroidal anti-inflammatory drug like ibuprofen or naproxen, something like that. Then that helps to ease your, that sense of malaise and cough and sore throat.
And he also suggests taking an antihistamine. And the one that he suggests is the older, they're called first-generation antihistamines, the kind that make you drowsy like Benadryl or Chlor-Trimeton. These are the sedating types of antihistamines. And those will help relieve runny nose and sneezing.
It's important to note that the newer antihistamines, such as Claritin, which are really designed for allergies, do not have this beneficial effect on the cold.
But taking those two drugs, the anti-inflammatory drug, you know, most of us know them as pain relievers, and these older antihistamines, it will ease your symptoms. And also, it limits the buildup of nasal fluid, which can actually lead to secondary infections. If you have too much nasal fluid, sinusitis is a very common complication.
I also use a saltwater gargle to relieve sore throat and those nice lemon-mint throat lozenges, which I actually think help relieve cough. These things all -they make you feel better while you're getting better. They don't actually shorten the duration of your cold. They're not curing you. They're just making you feel better while your body gets you better.
DAVIES: Well, Jennifer Ackerman, thanks so much for speaking with us.
Ms. ACKERMAN: Thank you, it was a pleasure.
GROSS: Jennifer Ackerman spoke with FRESH AIR contributor Dave Davies. Her new book is called "Ah-Choo! The Uncommon Life of Your Common Cold." You can read an excerpt on our website, freshair.npr.org. I'm Terry Gross, and this is FRESH AIR.