Student Questions: Hangovers, Manuka Honey, and Probiotics

Once again Skeptoid answers a round of questions sent in by students all around the world. This week's questions include what types of liquor will produce the least hangovers (always an important question for students); whether horse milk and manuka honey are miracle cures or just more worthless scams; what effect storing a car battery on a cement floor will have on its charge; how well certain ancient texts translate into other languages; and what's the real value of taking probiotic supplements to reduce gut-related side effects during a course of antibiotics. Let's begin with an important question from a studious medical school pupil:

Different Drinks, Different Hangovers?

This is Aaron from the NYU School of Medicine. People claim that different types of alcoholic beverages produce different physiologic effects, such as some types causing worse hangovers. How could this be true?

True it is. There are two basic things that cause hangovers. First and most obvious is the amount of alcohol in a drink. When you consume one unit of alcohol, your body expels three to four units of water, causing dehydration. This water loss causes shrinkage of your tissues, and since your skull doesn't shrink, your shrinking brain pulls on the connective tissues and causes a headache — the main feature of a hangover. Drinks with more alcohol cause worse hangovers.

But there's also a second cause independent of how much alcohol is in the drink. As the different ingredients of different alcoholic beverages ferment, other chemicals are produced besides alcohol, collectively called congeners. The congeners are what give different alcoholic beverages their colors, aromas, and flavors. Congeners include acetone, acetaldehyde, and tannins, which contribute to different hangover symptoms to different degrees. As a general rule, darker colored beverages contain more congeners than lighter ones; and lesser-processed drinks (usually cheaper) contain more than more-processed (usually more expensive) drinks. Whether you're drinking beer, wine, or liquor, clear top-shelf drinks will usually produce less intense hangovers.

Horse Milk

Marlon Roukema, student from the Netherlands. My question is, HORSE MILK. A miracle cure or just very expensive milk powder. Thank you.

There's a pretty easy way to tell if a product is actually a good medical treatment or just an expensive (and useless) fad: see if the literature on it is scientific or marketing. In the case of horse milk, also sold as mare's milk, virtually its only mention on the Internet is by mail-order companies selling it with claims of miraculous health benefits. I found no decent research papers at all finding that there's any value in it. The same goes for camel's milk; it's widely and freely available where it's made, so why not sell it to foreigners with amazing claims for ridiculous money.

Horse milk is big in Mongolia. But this isn't because Mongolians have found some secret of ancient wisdom; it's because horses are the dairy animals there. Mongolians usually ferment it into an alcoholic beverage called airag to preserve it. Probably this connection to Asia — always attractive to alternative-crazy Westerners — is what made it popular.

Manuka Honey

Hello, I'm Imogen from Cambridge in England, and I'd like to ask, is there any evidence to support the use of Manuka honey for anything else than sweetening food? A supermarket near me charges over £30 per jar. Is it actually the miracle product that it claims to be?

Manuka honey is a strong, dark honey that comes from New Zealand and parts of Australia. And, as with almost every substance, someone somewhere is selling it as a miracle cure for disease.

Various honeys do have different chemical contents, since the bees producing them feed on different plants. Manuka honey is among those high in methylglyoxal, which is an antimicrobial. When applied topically in wound care, weak evidence suggests that manuka honey may be an effective antibacterial treatment. However it's not likely to be as effective as medical antibacterial treatments, and no large studies have ever found a superior benefit.

Some cite the fact that manuka honey contains hydrogen peroxide. But it only contains as much as any other honey, and we now know that hydrogen peroxide is virtually worthless as an antibacterial agent.

For some reason a lot of supplement manufacturers sell manuka honey in pill form, claiming that it treats disease if taken internally. This is nonsensical; its proper use is topical, not systemic. As a food or sweetener, manuka honey is as good as any other honey. As a topical antibacterial for minor wounds, it's probably better than nothing at all. As a health supplement, it's completely worthless — so save your £30 per jar.

Batteries on Cement Floors

Hi, Brian. This is Jim Johnson in Vancouver, Washington. It seems to be a common notion among auto mechanics and others who work with batteries that a charged battery loses its charge more quickly when stored on a concrete or cement floor, and even charging a battery on a concrete or cement floor affects its ability to take a charge. These notions seem implausible since automobile batteries are housed in non-conductive plastic, but is there anything to them or do they amount to urban legends? Thanks.

This is my favorite type of urban legend, and the reason is that there is real historical fact behind why the legend exists. Lesser urban legends are simply not true and that's the end of them; but this one actually used to be true.

There were two potential causes for cement floors and batteries not getting along, and they both depended on the fact that car batteries used to be cased with hard rubber. If the cement floor had any type of moisture in it at all — which they usually do — that moisture could cause the rubber to swell, potentially cracking the glass cells in which the battery acid was housed. The battery acid would seep back down through the rubber, and damage the cement floor. Alternatively, the moisture in the rubber could cause a conductive path from the battery acid, through the moisture in the cement, and to the ground, thus causing the battery to discharge quite quickly.

But as has been the case throughout recent decades, battery cases are no longer made of rubber and glass cells are no longer used. They're made of polypropylene, which is impermeable to both moisture and acid. So there is no longer any way that a cement floor can be detrimental to modern batteries. In fact, because cement is such a good thermal heat sink, putting your batteries on it can actually keep them cooler, which slows the rate of the chemical reactions inside them that cause all batteries to naturally discharge over time. So embrace your cement.

Books Best in the Original Language?

Hello Mr. Dunning my name is Jeremiah Leonard. My question is: Can the Kuran only be read in Arabic? Can Shakespeare only be read in English? Are there certain languages that are so nuanced that they are virtually untranslatable?

Generally, the answer to this is no. Certainly there are concepts in various cultures that are harder to understand in other cultures, but keep in mind that a language is usually more flexible than a culture. For example, it's easy for you to imagine and describe a concept or an idea that would never be prominent in your culture. Think of two cultures, with the entire breadth of ideas comprehensible to each represented by a Venn diagram. No matter how different those two cultures are, the Venn diagram is going to be nearly all overlap. In my culture we would never think of eating babies as a way to gain strength, but note how easy it is for me to comprehend and express the concept in language.

While a literal phrase-for-phrase translation of even the most nuanced work might not make very much sense, that's due only to the mechanics of the languages, and not to any conceptual limitations. Lingua franca refers to a common language that two people can use to communicate. Sometimes it is the native language of one party or another; sometimes it is an agreed-upon third language. It would be a pretty rare case that two parties fluent in their lingua franca would be unable to share and mutually understand even the most abstract concept.

Probiotics

Hi. I am Jason from Ohio. My doctor prescribed for me to take antibiotics twice a day for a while and I read online that taking probiotics — pills supposedly filled with healthy digestive bacteria — will help to keep my digestive tract in balance during my antibiotic treatment. Is there any truth in this?

This is a really interesting question, lots has been written about it. The culprit here is AAD, antibiotic associated diarrhea. Besides attacking whatever bacteria is behind your particular medical problem, antibiotics are also suspected to have a detrimental effect on your gut bacteria, particularly in high doses or in longer treatments. This may result in diarrhea which usually lasts until you finish taking it.

In elderly people and other high-risk patients, diarrhea can potentially be dangerously dehydrating. Many researchers have tested whether taking a probiotic supplement might help replenish the gut bacteria during antibiotic treatment. Probiotics are essentially just live bacteria cultures, similar to what you'd get by simply eating yogurt. Now if you do a search through the literature, you're going to find a lot of research that finds there may be a benefit, and a lot of research that finds no benefit. Naturally any site that sells probiotic supplements is going to claim that the evidence is clear, but that's far from true.

The latest high quality study, published in 2013 in The Lancet, found no decreased incidence of AAD in elderly patients who supplemented antibiotic treatment with probiotics. The study followed 3000 patients in five hospitals and was properly blinded and randomized, so it's a very good result.

Here is the summary. Probiotics are definitely not going to hurt you. You probably don't need them. If you want them, just have yourself a nice yogurt, and don't expect much.

Students, keep those questions coming in, it's easy to do with your smartphone's voice recording feature. Just come to Skeptoid.com and click on Student Questions, where there's a form and some simple instructions. I look forward to hearing from you.

By Brian Dunning
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