Monday, August 28, 2006

More Medical Myths

More medical myths I wish I could put down forever:
  1. Drinking lots of water is good for you. NOT TRUE. (Yes, this is a repeat from my last medical myths post, but it seems to be the one people are most skeptical about, so I think it bears repeating. I'm not lying, y'all.) This myth probably started because of a misunderstood study long ago that the average amount of water a person uses for the business of existing for 24 hours is equal to about 8 eight-ounce glasses of water. The misunderstanding is that this is not EXTRA water; it's the water that already exists in all the foods and beverages (including caffeinated ones!) a person takes in during the day. Thirst is actually a wonderful mechanism for telling you how much water you need. Extra water does not benefit you. It doesn't help constipation, it doesn't help your skin, it doesn't benefit your kidneys (unless you have kidney stones), it doesn't help you exercise. Perhaps it helps some people avoid eating and drinking a lot of fattening junk, but this is questionable. What it DOES do is make you pee constantly, and in some instances can actually kill you. The water myth is reprinted in every issue of every health and beauty magazine published, so I have little hope of it dying.

  2. Bedrest prevents preterm births. NOT TRUE. I know that it seems to make sense—it must help to "rest," right? And if you stand up, the baby might just fall out!—but studies have shown that it's useless. So why does nearly every OB in the country keep recommending it? Well, think about it. What if they didn't recommend it, and a baby is born prematurely? Yeah, they could be sued, but also, they'd feel awful. If they prescribe bedrest and the baby is born prematurely anyway, everybody says, "well, at least they did everything they could." And what you'll often hear is, "it may not help, but it can't hurt"—a saying that really lights my fuse. In fact, it can be harmful—scratch that: it almost always IS harmful. Maybe only slightly harmful, in that the mother becomes physically deconditioned and has a harder time with delivery and postpartum recovery, and in that the mother gets put out of work earlier than she may have wanted, but sometimes very harmful. I'll give you an illustrative anecdote: a woman who works in my institution as a secretary has preterm labor at twenty-some weeks, and was put on strict bedrest. Weeks and weeks. She nearly went crazy, but even worse, she developed a blood clot from inactivity. So she had to go on blood thinners to prevent her from dying from a blood clot to her lungs. And then had a terrible GI bleed from being on blood thinners and had to have a transfusion. So bedrest almost killed her TWICE. But did she even think about suing the doctors who prescribed bedrest? Of course not, because she believed that she had to do all of this for the baby's sake, and the baby was born healthy.

    I think the bedrest myth is also harmful in that it adds to the fear that women of childbearing age might be a liability in the workforce. There's a doctor in my institution who is on her third month of bedrest, and the burden on her department is substantial. I wouldn't be surprised if they hesitate to hire the next 30-year-old woman who applies for a position. But god forbid a pregnant woman has any problems and DOESN'T go on bedrest. Oh, the guilt! I had preterm contractions (rather than true preterm labor, in which there are cervical changes), which has not really been shown to predict early delivery, but there are plenty of women who are guilted into bedrest for even this condition, and people tried it on me—"Don't you realize that your baby is more important than your job?" (Part of the whole infuriating pregnant-woman-as-vessel thing.) I was fortunate to have a super-smart OB who is also my good friend, so I had someone backing me up in refusing to be put to pasture, but few women are this lucky.

    I think that the biggest obstacle to making people stop putting women on bedrest is that almost nothing has been shown to be effective in the long term to prevent threatened preterm delivery, and until there's something that CAN be done, it's very hard to get people to stop doing things that don't work. (There was a recent meta-analysis that old-fashioned progesterone might be helpful—keep your fingers crossed.)

  3. Taking lots of vitamins is good for you. NOT TRUE. Taking a regular multivitamin probably isn't a bad idea, but in most studies, high doses of vitamins have been shown to be either useless or harmful. (The studies that show possible benefits get lots of press; the later ones debunking them, very little.) Fat-soluble vitamins (A, D, and E) can build up in your tissues, causing hypervitaminosis. Water-soluble vitamins (the B vitamins and C) are generally excreted by your body if they're not needed, though they'll turn your pee nearly fluorescent. Folate (vitamin B9) helps prevent neural tube defects in embryos, but it's added to all grain products these days, so deficiency is much more rare than it used to be.

  4. Refined sugar is worse for you than honey. NOT TRUE. Sweet things in excess are bad for you, whether their sweetness comes from refined sugar, raw sugar, honey, fruit, high-fructose corn syrup, or whatever else is invented next. (I'm reserving judgment on artificial sweeteners for now, but kicking the sweet habit altogether is probably better than relying on these.) What do I mean by "in excess"? I can't describe it, but I know it when I see it. Or eat it.

  5. If something is herbal/all natural, it's safe. NOT TRUE. For all its faults, the FDA does do a fairly good job of ensuring that drugs that enter the marketplace are reasonably safe and effective. But the FDA is powerless over "nutritional supplements" and herbal medications. It's not that herbal remedies are necessarily useless; several prescription medications have been developed from herbs, in fact. It's that they are almost entirely unregulated. There is no guarantee that what is printed on the side of a bottle of, say, milk thistle is a true representation of what lies within, and plenty of evidence that it is often a gross misrepresentation. There are some real rip-offs out there. And some herbs are powerful poisons.

    Somehow people started believing that doctors can't be trusted when we warn against natural remedies because we're biased against them. I'm not sure why we would be; we recommend plenty of things that don't require a prescription: a good diet, exercise, good sleep habits, quitting smoking. All of these things are all-natural and patient-initiated. And we'd love it if someone found a miracle cure for, well, anything, regardless of whether it required a prescription. I don't mind if a patient wants to try something herbal (in fact, I'll admit it, I'm happy if they get a placebo effect), as long as it's reasonably safe and not expensive. I just don't want my patients shelling out lots of money for anything that is useless and/or harmful.

(I know I'm coming off as anti-granola, and honestly, I'm not; I'm probably crunchier than most people think.) (Though granola can have a surprisingly high sugar and saturated fat content ...)

Any more myths you'd like to have debunked?


Mignon said...

I had a friend that had a near-panic-attack when she missed a day of her pre-natal vitamins in her third trimester. My understanding was that they are most important in the first trim. for the folate, and in fact with baby#2 my OB didn't even prescribe them, but recommended an over-the-counter product if I was worried. I think the What to Expect book breeds paranoia, including this vitamin neurosis, what think you?

kj said...

What about not eating after 6pm? Does everything you eat after 6 "turn to fat" since you're sleeping?

Hoping said...

oh this is fun. what about cranberry juice for bladder infections, does it have to be 100% juice and does it really even work at all?

does propping your hips up after sex really help in the "sperm swimming upwards" process?

Julie said...

Thank you SO MUCH for #2. I get feverishly het up by that one.

Klynn said...

What's your take on bedrest for someone with pre-eclampsia, and developing HELLP syndrome. Did they do me a disservice by putting me to bed for a week before the HELLP got so bad we had to do an emergency c? Thanks.

Michelle said...

I love these -- I wish you were my doctor.
How about fish oil and flaxseed oil supplements? A perinatalogist recommended I take fish oil daily during my first pg, another piece of "we dont know if it works but it wont hurt" advice. I've also had people tell me they swear by flaxseed oil.

Feral Mom said...

Is it true that grape juice is as good for you as a glass of wine? If so, excuse me while I go hurl myself off a cliff.

med school mama said...

When you have a snotty cold, does eating dairy products create more snot? Sure feels like it but others insist not.

Amy said...

how about the myth that you have to work at getting enough protein? Oh yeah, and that cow milk is good for humans?

wavybrains said...

Along with the supplements one, what's your stance on the "supplements are better for you than antidepressants" rhyme that gets repeated in book after book.

ozma said...

I love my herbs. Oh, how I love them. Don't take them away.

I'm all for the placebo effect, myself. I don't know if this is all placebo effect but I don't care as long as they work.

The most amusing ones to me are the ones that refer to 'chemicals.' As if there are things without chemicals. Isn't water a chemical? But I guess what they mean is not chemicals entirely, but pollutants. I wonder how those are scientifically defined. One man's pollutant is another mans stock option but there must be a scientific definition somewhere.

The others have to do with anti-aging creams. Even the term 'anti-aging' is amusing. Stop aging in its tracks! (Use this cream. You shall never die.) I almost hang around the cosmetics counters just so I can have hilarious conversations with the saleswomen. "Cellular recovery cream"! Does it cure cancer? Can we regrow amputated limbs with it. Another woman told me that there was a chemical in a night cream that went to your brain and gave it a signal to grow more collagen. Also, I was assured that the designer of another skincare line had "won the Nobel prize." Damn, I need to go back there and find out what line it was. What if it were true? (Of course, being a Nobel prize winner doesn't say anything about your integrity.)

I also wonder about the myth of water. I remember once I was drinking the tap water in someone's apartment and everyone was drinking the filtered water and I started to think: Is this water going to KILL me or something? Talk to some people and they definitely think so.

I know sugar isn't good for you. But does it cause insanity and early death? The hippies I used to know sure thought so.

The myths I always think of are the hippie/yuppie paranoia ones. They aren't myths, entirely, because some plastics do have carcinogens. But the terror of plastics seems misplaced. Or just the terror of the products of the modern world generally. Ocassionally, I get it myself. It's due, no doubt to the fact that there are a terrifying number of pollutants in the world, mysteriously declining fertility rates or what have you. But really. We do live pretty long over here. Let's try to minimize the scary crap we put into the environment but let's also admit that avoiding the scary crap is next to impossible.

Finally, I've found that 'calories in, calories out' is a total myth when it comes to my body. No one will believe me, of course! But let's wait a decade or so. I feel confident I shall be vindicated.

Kristine said...

Yes, I believe nothing actually stops preterm labor if it is truly labor. But I do think in a viable, early preterm gestation, it's worth trying tocolytics for 48 hours to get steroids on board for fetal lung development. That has been proven to change outcome. Same story for preeclampsia/ HELLP syndrome in my opinion. But you can't fight city hall in this law-suit happy society.

DoctorMama said...

mignon—What to Expect breeding paranoia? Ya THINK? Actually their baby & toddler books seem ok, but the pregnancy one is for the birds. Panic-attack-prone birds. And folate is actually most important PREconception. By the end of the first month or two, that horse has left the barn.

kj—well, hm. There is some evidence that those who eat most of their calories late in the day get fatter than those who pack it in early, but it’s not an absolute kind of thing, and it’s hard to tell whether the relationship is causal. Perhaps when you eat late, you don’t give your body a chance to get more active to deal with the extra calories (which people have been shown to do).

hoping—cranberry juice—maybe? A tiny bit? Or maybe not. And if it works, probably doesn’t need to be actual juice.

As for post-sex hip-propping—who the hell thought that one up? The same person who as a teenager believed that jumping up and down afterward was an effective contraceptive measure? I know of no evidence for this one. I did it a few times, but it just seemed too silly for words.

julie—whenever I hear of yet another woman put on bed rest I get so mad I can hardly see straight.

klynn—I’m thinking you were kept in hospital for this period? In which case they WERE following the current evidence: expectant management of preeclampsia (i.e., monitoring the mother and fetus closely in the hospital setting and taking the baby if things start to go downhill) had better outcomes than “aggressive” management, where they delivered as soon as possible. If the baby is doing ok, the longer it can stay in, the better, as long as the mother isn’t put at risk. If you were on home bedrest, well, that makes no sense.

Michelle—fish oil MIGHT be helpful in cardiovascular disease, but the studies are still in the happy-dippy stage of preliminary tantalizing hopeful results that are prone to debunking when proper studies are done. I don’t know about them in pregnancy, or flaxseed either.

Feral—studies have shown that if you give up all alcohol and accept Christ as your personal saviour, you will go to heaven and not care that you died young. (Unless you’ve committed suicide by hurling yourself off a cliff, then you’re not eligible.) Seriously, the health benefits of alcohol apply to ANY alcohol—including, I’m very sorry to say, Peach Schnapps. Grape juice has some decent stuff in it, but the alcohol does more magic. (And juice is sugary, anyway.)

med school mama—NO. You’re right, it FEELS like it does—all sticky in your throat—but this is an illusion.

amy—I don’t know, but I’ll try to find out.

wavybrains—is that really you, or is this Tom Cruise in disguise? Seriously, there is NO science to back up that claim. What “supplements,” anyway? A lot of people self-treat depression with alcohol (a “supplement” if I ever saw one), to spectacularly ill effect.

ozma—don’t worry, I’m not going to confiscate your herbs. I wish I could get a good placebo effect going myself, but I’m sadly impervious. I’m with you on the anti-aging creams. Believe me, doctors do not spend $300 per ounce on Master Science Swiss Bull Testicle Rejuvenation Bounce, because that stuff don’t work. I do anxiously await your debunking of the calories in/out dogma.

kristine—yes, if you can figure out a way to buy time for steroids to work, that seems to be beneficial. And discussion of preeclampsia above.

Claire said...

Loving your blog!

Anyway, I thought red wine was the shizzle with the splendid anti-oxidant called something (starts with R.) That was all you know, 'kapow to plaque on artery walls'. Not that I've got anything against peach schnapps, just love me some red wine.

Any goss on trans-fats and 'fat free' type foods huh huh? I'm talking about the weird fat free ice-cream etc. Anything on the French paradox? Anything you tell me about why eating real cheese with real fat is better for me than some weirdo cheese processed thing would be good.

Sydney said...

Are there ever times that bedrest is essential? I was wondering about a condition such as placenta previa, is bed rest and propping those feet up helpful for that? I've never been pregnant and I read medical records all day, so my experience is purely on paper. Thanks for taking the time to answer our comments.

Vacant Uterus said...

Can you direct me to any studies re: the vitmain myth? My best friend INSISTS that 20,000 mg of Vit. C a day will keep her healthy and that she isn't getting the proper amount of what she needs from a multi. And she takes a prenatal mulit, even though she's no longer pregnant (she is nursing, though.) I'd love to be able to give her some better information.

I am one of those excessive water drinkers. But mostly I do it because I'm just that thirsty.

Not Yet said...

Recently a blog got me thinking about my husband's comments as he walks around going "Damn, they didn't grow teenage girls like that when I was young!" The blog referenced the natural plant hormones of soy and the possibility that it is causing infants to ingest something like 5x the amount of hormones in birth control pills in a soy baby formula. If this is true, how much soy is being grain fed to our commercial meat (and various other food items), and what is this doing to my body?

Spinoff said...

Okay, so the week I spent lying on my left side because of blood pressure readings of 210/140 (went down to 180/100 reclining) were for naught? Go figure. Well, the kid in question is now 20 and I'm here to tell about so I guess all is good.

Meira said...

Not a myth, but I was wondering: What's the difference between 0.9% Sodium Chloride vs Lactated Ringers for sub-q hydration?

(As background, the vet rx'd my cat lactated ringers, but the next time I called for a refill I made a mistake and asked for sodium chloride . . . I couldn't tell any difference except that the cat was slightly more annoyed to be getting the sodium chloride.)

Anonymous said...

Ok, you kind of touched on this, but what about the myth that caffeinated beverages actually *dehydrate* you. My sister-in-law is a big promoter of this one (and of the YOU WILL DIE IF YOU DRINK LESS THAN 8 GLASSES OF WATER A DAY theory, and it's corollary, the more water you drink, the more you will flourish). It's my pet peeve, and it makes me want to dump my hot coffee on her head.

And just as an aside, here's what I don't get about those water-crazy people: How do they think humans have survived until now? Indoor plumbing, easy access to potable water, and, shit, drinking glasses for that matter, are all relatively recent inventions. So how did humans get their 8 glasses of water a day when we were chasing game across the prairies?

Anonymous said...

I was put on bed rest a month and a half out from my due date, but went insane with boredom after a day. I figured "what could biking hurt?" so logged about ten miles a day with my dogs up until the week before when one dog smacked my bike wheel with his head, over I went, bike on top and ankle broken. Glad I did avoid the bed rest though, because the labor dang near killed me, and probably would have if I wasn't in great physical shape at the time. I had blood pressure spiking too, but the 8 hours a night on my left side, coupled with naps, seemed to keep it under control. Kidlet is 17 now, having survived the bike accident, labor and 17 years of life. :)

Klynn said...

Grrr. Nope, it was home bedrest. And it took several trips to L&D and rounds of bloodwork to finally show them that I had HELLP (I knew it was coming, because I had it in my previous pregnancy, and I could feel it even before the bloodwork showed it). By the time the bloodwork showed it, the OB sent us directly for the emergency-c. I bet if they'd admitted me things might have gone a little better, even if it didn't lengthen the time he was in there.

Thanks so much for addressing my question. Love your blog!

Lisa said...

The ones that make me pull out my hair:

1. Teething causes fevers
2. The flu shot will give you the flu
3. Put toothpaste on a burn, and put coffeegrounds on a bleeding cut. Do people realize how hard it is to get that shit off when it comes time to debride the burn or sew the laceration???

The MSILF said...

Whoa! I never heard that about coffee in a cut. I can't imagine how furious I'd be digging that out of someone in the emergency room.

DoctorMama and friends, can we start a health TV show based on evidence based medicine and yelling at all the "alternative practitioners?"

Loved this post.

LL said...

How about the old wive's tail (that my ex still subscribes to) that you shouldn't drink milk when you have a fever, because it will curdle in your stomach??

Amber Lawbyrd said...

I did a bit over 42 weeks of bedrest over 3 pregnancies. Hellacious. The worst was the 5 weeks of continguous hospital bedrest after I had PPROM in my 1st pg, where I had to lay down, use a bedpan, and wasn't allowed to shower, in a hospital where no one would speak English to me, and all the food gave me heartburn. I had HG as well, so I was also puking the whole time. My last dr. still put me on bedrest, but at least he let me use the potty & shower. Only way I kept my sanity.

I love hearing you talk about the water myth. I really dislike drinking water, so it's always a relief to hear.

I want to know if it's true that any person can become as flexible as they want to be? I argue with my martial arts instructor about this all the time as I am always getting injured during our stretching classes (torture classes).

Old MD Girl said...

Yes, yes, yes. Especially to the vitamins and herbals points. And as I learned in class yesterday, too much vitamin A is teratogenic. I.e. it will cause your fetus to develop wrong. In very very very bad ways. And that HAS been backed up by studies.

Amy said...

While I agree with you that lots of people over emphasize the water thing I can tell you that, for me, it is a necessity. I have suffered from chronic urinary tract infections from the time I was about 5 years old. It is difficult to explain to people the absolute misery that dealing with them caused me over the years. The ONLY way to prevent them for me is to drink lots, and lots, and lots of water (and yes, cranberry juice – even the sweetened kind – will reduce symptoms. But due to the high calories and sugar it really isn’t something you want to rely on on a regular basis.) My husband insists that I am the worst person on earth to take a road trip with but I really don't care. I would much rather have to run to the bathroom a lot than be sick and in pain. On the rare occasions where I don't have my giant water bottle with me and have a chance to refill it throughout the day I can guarantee that I will develop UTI symptoms within 24-48 hours. If keeps me from feeling sick and miserable all the time I will deal with having to go to the bathroom ever hour. And yes, I could replace water with another beverage but then I can almost guarantee I would be taking in excess calories, sugar, caffeine or chemicals. Water is really the best beverage choice.

And correct me if I'm wrong but Hyponatremia is EXTREMELY rare in healthy individuals who do not engage in endurance sports. Unless you are elderly or have kidney problems your average person who is trying to drink 8 glasses a day is not at risk. So while I agree that for most people it isn’t necessary it also is unlikely to cause any harm. In that instance we tend to be replacing other beverages and food with water. We all also tend to consume a lot of sodium in processed food so drinking more water (within reason) will simply cause your body to release the water it retains rather than severely distort the balance of electrolytes in your body.

Gallaudet said...

The one that makes me want to spit and scream is: vaccinations cause autism and damage the immune system.

My SIL recently informed me that she didn't vaccinate her sixth child because, "She just looked at me when that first needle went into her arm, and I knew somehow it was wrong." Then she went and consulted Dr. Internet and decided vaccines are "full of impurities." To which I say: you feed your kid hot dogs?

margalit said...

THank you for posting about drinking too much water. It is extremely dangerous for older people, especially those with heart problems, to drink too much water. I ended up almost dying of congestive heart failure due to my excessive water drinking. I had no clue that that appeared to be bad asthma and a terrible case of heartburn was actually caused by excessive water drinking, which so damaged my heart that I ended up hospitalized. I'm restricted to 4 8-oz glasses of liquid per day, and to ensure that the water doesn't build up, 40 mgs of lasix daily. It's a sucky way to live and I don't wish this on anyone.

Please keep continuing to talk about excessive water drinkage.

DrSpouse said...

Oh &*)(*&, the vaccination and autism one. Cause of new mumps and measles epidemics...

I can think of several psych myths too, but I won't bore you with them.

In the UK flour is not (yet) fortified, and sadly, the "women's multivitamins" on the whole don't even contain the right dose of folate, which is pretty annoying, to say the least.

Laura said...

professionally and intellectually I know #2 just does not prove to be true. But emotionally I accept it...while pg with my #4 daughter, I was diagnosed with PTL at 24 weeks. I was dilated 2 cm and 25% effaced and had history of fast labors. Yet when my OB placed me on complete bedrest with tocolytics, to bed I went. Two weeks later, my water broke oaking our queen size bed. I was hospitalized, tocolyzed even more, shot up with steroids and antibiotics and pushing fluids like crazy. I continued to leak amniotic fluid for 6 more weeks and contract no less than 4-6 contractions an hour on a good day for 12 more weeks. My daughter was born at 38 weeks with no complications. It was 99 days of sheer hell and fear but I would do it a million times again because it is so worth it everytime I see her smile.
yeah, it's myth but I'm bliever. Who could blame me.

DoctorMama said...

Claire—antioxidants have turned out to be duds so far, but alcohol in moderation does seem to have a protective effect. May or may not be causal, but seems to apply to rotgut as well as good cabernet.

As for trans-fats, fat-free ice-cream, the “French paradox” etc.—it’s still not clear why, but it seems you can’t fool Mother Nature. The stuff that we invent to try to trick ourselves into believing we’re eating the real thing just fails, either in that it doesn’t fool us, or it’s bad for us in another way, or it makes us eat more. The French seem good at eating sensible portions of real food, but I think they’re starting to slip, too.

So, eating real cheese with real fat (in moderation) DOES seem to be better for you than eating the fake stuff, but research is too young to really tell us why.

Sydney—well, periods of daily rest MAY be of use when a mother’s blood pressure is elevated. And bedrest in a hospital setting can be helpful in that it provides near-constant monitoring of the mother and fetus, and therefore allows the fetus to continue developing until the last possible moment. So if a fetus may require early delivery—for preeclampsia, for example—hospitalization can help. For previa, no, bedrest has not been shown to be helpful, except in the way I just described. (Doesn’t mean people don’t try it, of course.)

Vacant Uterus—I am almost positive that the friend you describe will not be swayed by studies. And I never meant to say that anyone who’s otherwise healthy shouldn’t drink if they’re thirsty. (Unless they come to me complaining of insomnia because they get up 37 times a night to pee off the excess.)

Not Yet—re: soy infant formula & etc. The answer is, “… more studies are needed.” Nothing obvious is showing up as a real problem; doesn’t mean it might not in the future, but I wouldn’t put it at the very top of your worry list.

Spinoff—hypertension is one thing that periods of resting (though not strict bedrest) may help. Or not.

Meira—we did that with our cat too! Isn’t it trippy, jabbing that needle in and they don’t even seem to notice? Anyway, I really don’t know if it would hurt more to use the one instead of the other … we mostly just use 0.9% NaCl on people.

Anonymous—the reason the “caffeinated beverages don’t count” myth started is that caffeine has a teeny-tiny diuretic effect, but this quickly wears off, so it essentially makes no difference. (But I bet your SIL is extremely healthy, shiny, and kind because she drinks so much water.) Basically, the kidneys rock; they’re why we don’t usually need to worry about our fluid balance.

Anonymous—you rock too. What did they say when you showed up with the fractured ankle?

Klynn—ugh, I’m sorry. I’m glad your little guy ended up fine.

Lisa—it is SO HARD to convince people that the flu shot cannot give you the flu. (It’s easy to see why, though: flu shots are given at the beginning of cold & flu season, and a certain number of people will be coming down sick just when they get the shot, and it’s human nature to decide that if B happened after A, then A caused B.) I had never heard those other myths—yikes.

The MSILF—sounds fun, but I don’t think “EBM—The Reality Show” would get very good ratings. (By the way, I don’t mean to rag on all “alternative” therapy; every therapy was unproven at some point. The ones that get my goat are the ones that persist despite good evidence that they don’t work.)

LL—never heard the fever/curdled milk thing either. But you know what? Milk ALWAYS curdles in the stomach.

Amber Lawbyrd—almost a year of your life in bed? Geez. I hardly know what to say to that. (I have had the experience of being stuck in a hospital where no one would speak English to me. So terrifying. Makes me try to work extra hard to get an interpreter when I see non-English speaking patients.) Re: flexibility—some people have looser ligaments than others, and you can’t change the composition of your collagen. But I expect it’s futile to try to convince your instructor of that.

Old MD Girl—re: vitamin A and teratogenicity—I didn’t mention that in my post because I don’t want anyone to freak out over the vitamins they’ve been taking. Yes, animal studies have shown such an effect, but they haven’t found hard data that it’s dangerous in humans at anything like the doses most people can get their hands on. Retinoids are VERY teratogenic, however, when taken orally (Accutane, I mean—topical retin-A cream has NOT been shown to be a problem.)

Amy—hey, if you need your water, you need it; it’s just that most people don’t. And yeah, water is a lot better than just about anything else. Re: hyponatremia being rare—yes, thank goodness. But the scary thing is that since this whole water craze started, otherwise healthy people who are not exercising terribly hard HAVE developed it, and that’s new—and preventable. But you’re quite right, the worst thing most people will suffer is too many trips to the toilet.

Gallaudet—I’ll just say it so that I can say I said it: Vaccines DO NOT cause autism. They DO save lives.

Margalit—good thing to highlight: if you have heart problems, you should in fact RESTRICT your water intake. It does seem like a sucky way to live.

DrSpouse—I’d like to hear the psych myths!

Laura—Who could blame you? Not I. I’m so glad it turned out all right.

Orange said...

Thanks for the "bedrest has not been shown to help in cases of placenta previa" info. A friend was sent home from the ER with no bedrest instructions, and the placenta shook itself loose a few days later, leading to a baby born at 26 weeks. Good to know that bedrest wouldn't have staved off the prematurity.

Anonymous said...

What's the deal with the contraceptive effect of breastfeeding? I'm holding out a teeny hope (age 40 with 7 IVF's under my belt - hahahahaha!) that, woops, I might get pregnant the old fashioned way. But I also want to continue feeding (though generally now that my daughter is 9.5 months this is only 2-3 times per day). My periods have been regular (and I'm a PCOSer, so this is a surprise) since 3 months post partum.

Breastfeeding as a contraceptive - myth or fact??


(the kidneys rock - love it!)

Monica said...

I know several people who can tell you that breastfeeding is NOT an effective contraceptive method!

Anonymous said...

I hope I join them...mind you, I've not used a contraceptive since, um, oh, 1995, so I might be a tad optimistic.


Rebecca said...

Brestfeeding is NOT an effective contraceptive! If you're not having periods you're probably safe but there's no guarantee. Once your period comes back you are 100% fertile. Ask my daughter who is only 15 months younger than my son.

emjaybee said...

My husband developed a horrible case of hives a few years ago from taking pumpkin extract (vitamin A) supposedly to help w/ his bowel problems. We didn't know that's what was causing it until he'd suffered through a month of steroids and itching and antidepressants and complete misery. Once we did figure it out, it took 90 days or so to get out of his system. Made me v. skeptical of all herbal supplements.

Hey, here's one: do raspberry teas do anything to help "ripen the cervix"? My midwives were big on this, but I don't think it does a damn thing. It does give me cramps when I'm not pregnant though.

Shirky said...

does cracking your knuckles harm the joints long-term?

Can I continue to say it does, because I detest that sound?

Kelly said...

How about the whole spotting-in-first-trimester-so-no-exercise-for-you thing? I gained 65 lbs in my first pregnancy thanks in large part to that one.

CaerLiveSound said...

I think Doctor Mama should run a weekly "Ask Doctor Mama" column! Look at all these neat questions!

mamamarta said...

exclusive, on-demand breastfeeding, with no supplements, no artificial nipples, and pretty much 24/7 contact between mom and baby is actually a very effective form of birth control in first half year or so post-partum. i wouldn't worry that your 9mo's nursing 2 to 3 times a day is affecting your fertility.

doctormama, how about these:

routine ultrasound in normal, healthy pregnancy is a recommended diagnostic practice.

the safest place to give birth, after a normal, uncomplicated pregnancy, is in a hospital.

routine, continuous fetal monitoring in a normal labor after an uncomplicated pregnancy improves outcomes for babies.

babies with severe jaundice should stop breastfeeding.

elective c-sections are perfectly safe for baby and mom.

epidurals have no effect on babies.

as a lay breastfeeding counselor, and someone interested in pregnancy and birth, i have to say that in my experience the medical establishment is just as guilty of disregarding evidence-based practices as the crunchy alternative folks are...

Rebekka said...

I have to take issue with a couple of things (love your blog, by the way!)

Refined sugar is worse for you than honey. NOT TRUE. Sweet things in excess are bad for you, whether their sweetness comes from refined sugar, raw sugar, honey, fruit, high-fructose corn syrup...

I don't think sweet things are good for you at all, and I hardly eat them, BUT honey contains trace elements that refined sugars do not, and may have health benefits including reducing fasting blood sugar -

(sorry, it never works when I try to make a link active).

I think that's a cogent argument for honey being at least a little better for you than refined sugars - although I think you're very much right when you say too much of any sugar is bad for you.

Secondly, dismissing a potential link between vaccines and autism is not as simple as dismissing a link between the MMR and autism. While I do not think there is a connection between MMR and autism, I do think there is a potential link between vaccines that contain the additive thimerosal and autism that merits further investigation. Studies such as this one ( ) that shows LESS mercury in the hair of babies who later developed autism suggest that autistic children may have a problem excreting mercury. It's not definitive, obviously, but there are other studies that suggest similar findings -


The MMR vaccine doesn't contain thimerosal, and I don't think vaccines in themselves contribute to autism. But I do think this potential connection deserves further study and should not be dismissed as a myth.

And finally, on the treatment of depression with herbs - several studies have found St John's Wort more effective than a placebo in treating mild to moderate depression, and for mild depression it is just as effective as anti-depressents, with less side-effects.

(and I also agree with everything mamamarto said!)

DoctorMama said...

Re: breastfeeding as contraception—what Rebecca & mamamarta said.

Emjaybee—I don’t know of any studies on raspberry tea & ripening the cervix. Interestingly, one of the most common methods used to ripen the cervix by physicians—laminaria—are derived from kelp & are an “herbal” method.

Shirky—cracking the knuckles probably doesn’t do long-term damage. Just tell them it drives you crazy. I don’t let anyone crack gum in my presence, even though I know of no health consequences to doing so.

Kelly—that recommendation is not based on any data, though it would be a very hard thing to study. This is one of those “depends” situations—depends why they think you’re bleeding and what kind of exercise you’re talking about. Spotting in the first trimester is so common that an awful lot of women would be prohibited from exercise if this were a blanket rule.

CaerLiveSound—too much pressure!

Mamamarta—whew, that’s a lot, but I’ll take a stab:

Is routine ultrasound in normal, healthy pregnancy is a recommended diagnostic practice? Well, this is becoming a moot question, I think. Older studies suggest that “routine” ultrasound does not benefit mother or fetus, but the availability of ultrasound (and advances in ultrasound technology) is increasing so rapidly that it’s very hard to compare now—you can’t find any un-ultrasounded fetuses anymore, or many pregnant women who don’t want an ultrasound. (There are of course places where the technology is not very available, but then the medical care is very different there as well.)

The safest place to give birth, after a normal, uncomplicated pregnancy, is in a hospital—does not appear to be true, though it has not been studied in a rigorous fashion. (Giving birth far from hospital care, should it be required, does appear to be riskier.) In the studies that have been done, the majority of women who are giving birth for the first time end up transferring to a hospital anyway (for good or ill); women who have had normal vaginal births in the past tend to do as well or better in non-hospital settings.

Routine, continuous fetal monitoring in a normal labor after an uncomplicated pregnancy improves outcomes for babies—not true.

Babies with severe jaundice should stop breastfeeding—of course not. In fact, every effort should be made to get them to breastfeed MORE.

Elective c-sections are perfectly safe for baby and mom—PERFECTLY safe? Certainly not true. Very safe? True. (I’m not a proponent of truly elective surgery in general.)

Epidurals have no effect on babies—Hmm. Epidurals have an effect on the mother; pain relief is much greater than with other methods, but with this comes a possible increase in the length of the second stage of labor, and a small increase in the risk of instrumental (forceps/vacuum) delivery. As for the baby: NON-epidural pain medications do have an effect on babies, but epidurals probably do not (even taking into account the risk of instrumental delivery). (Disclosure: I examined all of the evidence about this prior to giving birth, and I elected to have an epidural. I did indeed have a prolonged second stage and a vacuum-assisted delivery. I also have a wee pelvis.)

As for whether the medical establishment is guilty of disregarding evidence, absolutely; this is especially true in the surgical world (including OB), partly because of the malpractice environment—see my discussion of bedrest above! But is the medical establishment in general “just as guilty”? No, I don’t agree. But you probably don’t mean all doctors as compared to all “alternative” practitioners. I certainly think that there are many doctors who ignore evidence, and many alternative practitioners who heed it.

Rebekka—you are right, honey does contain trace elements that refined sugars do not. The study you mention, however, involves only ten subjects, which is too small a sample to draw much useful information from. (And the information they do obtain is very mixed; of the indices they mention, some are probably good things and some are probably bad things.) Honey can actually be dangerous for infants, however, and in balance, I think it does not have an overall advantage over refined sugar. (Especially since you’d have to eat way too much of it to get a benefit, IF one exists.)

Re: vaccines/autism/thimerosal—this is obviously a complicated issue. (And Bihari, I'm holding you responsible for getting me into it!) It’s my firm opinion from looking at a lot of evidence that vaccines do not cause autism, and I have had my son vaccinated for everything offered. Whether mercury exposure is implicated in autism is a different question; however, the most common way kids are exposed to mercury is through fish in their or their mothers’ diets, or via environmental exposure (living near a mine, e.g.). Thimerosal has never been shown to be a significant contributor to mercury levels—BUT it has been removed from pediatric vaccines anyway, just in case.

Clearly there is an increase in autism (apparently worldwide), and we don’t know why; we need to keep looking for the answer.

And re: St John's Wort—yes, I agree that this (and other herbs) may be effective—my complaint is that when you buy St. John’s Wort (or whatever), you have no guarantee of what you’re getting, or how much.

wavybrains said...

I just wanted to thank you for all your great answers to the Q's--I learned alot. And no, I didn't mean to sound Tom Cruie-ish at all. Just the oppisote---:) It seems like everywhere you turn someone is peddling "natural" antidepressants and "natural" cures for depression and bashing antidepressants which can make the need to take them seem like you are doing something bad/uneccessary/foolish :) :) Probably could have phrased that better. I enjoyed the other Q a lot too.

DrSpouse said...

Some great psych myths:

Boys are ALWAYS slower to talk than girls (in fact, of course there's a huge overlap, and the difference is about three WEEKS) so loads of boys don't get referred to speech therapists "because they're boys".

All types of "talking therapy" are the same - either they are great, or they are rubbish, according to your point of view. In fact, behavioural therapy and CBT have been shown to work, most of the rest are no better than being on a waiting list.

The MMR/autism thing is one of ours too. Lots of children who have autism appear to lose developmental milestones - this is probably because children start off by doing things in a "baby" way, then learn new, "child" ways of doing the same things (e.g. eye contact).

Babies can remember EVERYTHING! Including being in their mother's womb! And they can miss their birth mother even if they were separated from her at birth (just got slammed on someone else's blog for saying I didn't believe this). The fact that they learn to associate* the doctor's office with having a heelprick proves they can remember every detail, including having a fully-formed representation of their mother. The fact that basically we remember nothing from before we are 18 months, and that children under 6-9 months don't get upset when separated from their mother, proves nothing.

*NB NOT remember. Associate.

Babies are smart! No, sorry, they are dumb. They do not have fully functioning cortexes. They cannot do maths... (actually, that one's a matter of theory - some psychologists believe they are smart).

Anonymous said...

DoctorMama, I'm kind of defensive about your attack on water-drinking myth, since I've always drunk a lot of water and enjoyed believing that this was healthy. I'm almost willing to go along with what you say about it, but one question--doesn't drinking lots of water dilute the effects of excess sodium in your food?