1) I often have a bad taste in my mouth, and bad breath as well, I assume. This doesn't stem from poor hygiene: I brush my teeth at least three times a day, and usually more. I'm wondering if there is anything I can do about this. Could this be a symptom of some sort of nutritional deficiency? I think my diet is pretty bad, although I'm working pretty hard on getting more protein and eating less fat. I've also been nauseous a lot lately, and vomiting some. Could that be related?

2) Like many people, I often have an embarrassing bad breath. Listerine and other mouthwashes won't be of any help for this chronic problem. There are lots of products available to get rid of "volatile sulfur compounds (VSC)" - that supposedly cause this — and I just don't know which one I should try. Also, what's your opinion on tongue-brushing?

1) Which is better for you, tap or bottled water?

2) How bad is the water here in New York City? Do you recommend drinking filtered water, or does it really make a difference?

What is the significant difference between a product that is antiseptic and one that is antibacterial? All of the antiseptic mouthwashes I find have a great amount of alcohol in them. This can be very irritating to the mouth. I have found one that is alcohol free, but it says it is antibacterial.

Thanks for your help.

1) My girlfriend just saw her ob/gyn and was told that she has a mild yeast infection. Being that we are sexually active, is this something that I should be concerned about?

2) Can a guy get an infection if he has unprotected oral sex with a girl who has a yeast infection?

I'm a 21 year old woman with white lumpy vaginal discharge (odorless)...I thought it was thrush but after two courses of yeast infection cream it has not resolved...I have never had sex, so can't have an STD...I get bad pain in my lower back and sacro-iliac region with my period and with ovulation though I don't know if this is relevant...I'm embarrassed to see a health care professional about this and don't know if I'm just concerned over nothing...

So far I have been extremely impressed by your service. I trust you with a question which I know many people share: Are whitening toothpastes detrimental to the longevity of one's teeth?

I was told by my dentist that my teeth eroded, due to consumption of too much acidic food. I would like to know what kind of food causes tooth erosion. Do you have a list of these foods?

I have chronic yeast infections. My doctor basically said that I have a pH imbalance and to stock up on Mycelex or similar creams. This answer, to me, is unsatisfactory. There must be something I can do to keep my pH level in balance, or at least on the acidic side. Do lactobacillus and acidophilus tablets keep the vagina more acidic to prevent a yeast infection?

I’m having a burning sensation when I urinate and it still burns after I urinate. Also, I can’t urinate all the way and am continually having to go to the bathroom. I was diagnosed with kidney reflux when I was a child — could this be that?

I was having a conversation with my roommates about pop and coffee and we were wondering which is worse for your teeth, the pop or the coffee? And what do they do to your teeth when you drink them?

What causes fever blisters on lips and how should they be treated? Also, what is the difference between fever blisters and shingles?

I just came here this fall. Since then, my nose has been bleeding occasionally without any injury. My friend told me it was because of the dry air of U.S. Is he right? How can I prevent this situation? I also have a problem when I brush my teeth. My gums are always bleeding and not just a little!! What should I do? Thanks.

This week I'm getting my tonsils and adenoids taken out. I've never had surgery before and I don't know what to expect. Can you explain please?!?

I'm really stressed out because I've been getting recurring urinary tract infections coupled with yeast infections for the last six months. I'm not sexually active and I've been to two urologists and a gynecologist — they've all given me medication but the problems always turn up again. Is one problem causing the other? Can these prolonged problems be doing serious damage to my body? Perhaps you can't answer my questions either, but I'm really at my wit's end. What do I do? I'm tired of doctors and embarrassing exams and I can't understand why this is happening if I'm not having sex. Also, I'm a senior and in five weeks I'm out of health insurance — extending my parent's policy is very expensive and not an option. I'm busy trying to set up interviews, finish a thesis, and do a million things — I don't have time to be running around to more doctors' appointments! What insurance options are there for recent graduates?

I think I may have some kind of urinary tract infection. It came on very suddenly, about three nights ago. And when I pee, there is a burning sensation when my bladder has almost emptied. It's not an STD because I'm in a monogamous relationship, and yes, I'm sure! Please help. Thank you.

Is it bad to chew sugar-free gum? I heard the chemicals in them are bad for you to ingest?

When both of you have braces, and you do happen to get stuck together, is there any way to unhook without help from anyone other than you and him?

About six months ago, I experienced pain when urinating after having intercourse. Typically, I have pain/burning the first time I urinate after sex, but then the pain tends to go away or diminish. I am a 38-year-old male. I have no pain otherwise.

1) I'm considering getting my tongue pierced. Is there anything I ought to know before I get it done? What should I look for in a piercing place? Does the piercing ever have negative effects — I don't know, tongue paralysis or something? Thanks!

2) If and when I decide to take my tongue ring out, I worry that there will be scarring tissue or an ugly hole in the middle of my tongue. Is this the case?

If a guy has jock itch, can it be passed on to a woman in the form of a yeast infection during sexual intercourse? I had intercourse with a guy and he had jock itch. A few days later I got a vaginal yeast infection. Could there be a connection?

1) What is TMJ? What kind of doctor handles this problem?

2) I have a rather odd problem. For the past several years, I have noticed that when I open my mouth wide to yawn or take a bite out of a sandwich, the right condyle of my jawbone slips laterally from the temporomandibular joint, making it difficult, and at times, painful, to close my mouth. I basically have to slip the condyle back into the socket; otherwise, it slips in by itself, which is what causes the pain.

Other than being inconvenient, this has not adversely affected me in any way that I can tell, except that I am now careful not to open my mouth completely when I yawn. I am reluctant to see a doctor about this because I cannot reproduce the situation at will, and don't know if the problem can be diagnosed or detected unless the doctor actually sees the condyle slip out.

Also, any time I have gone to Health Services, it seems that whatever the problem, they just send me home with a jar full of ibuprofen. What do you think is wrong? Is this problem serious? Does it deserve immediate attention? What type of doctor would I need to see and could I get a referral from Health Services?

I am a 26-year-old female and have started getting a yeast infection every month without fail at the end of my period. This started about a year ago and I've cut back on eating bread, I don't eat much sugar and I rarely drink beer. I read online that someone recommended using a douche just before and after starting my period. Is this a reasonable thing to try? I've always been very opposed to douching but I'm sick of the itching and don't want to have to take medication or use cream every month. Any suggestions?

Here's a question I have been debating with a friend for a while, and seeing as how I'm not scheduled to go to the dentist again for a while, I thought you could shed some light on the issue: when brushing one's teeth, should one also brush one's tongue? I would think yes, because what's the point of brushing germs off teeth if the tongue still has them there, and will transfer them to the teeth as soon as you're done brushing. My friend thinks it makes absolutely no difference. So does it matter? We have an ice cream wagered on this one! I hope I'm right!