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.

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?

My boyfriend and I have been together for almost three years, and we've lived together for more than one, but I still can't do Number Two when he's in the house. It's not a problem during the week when we both go to our separate jobs, but on the weekends, it's usually just the two of us in the house all day (and night) Saturday and Sunday and if I feel the need to poo, I have to wait until Monday. My question is this — are there any adverse health issues I should be concerned about with waiting to poo? I know that holding your pee can give you bladder infections, but is there a similar issue with Number Two?