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Why should I brush my teeth in the morning? My teeth are just going to get dirty again when I eat breakfast 5 minutes later. Plus, I've already done an extensive cleaning (floss, brush, mouthwash) the night before. My teeth should not be getting dirtier as I sleep.

I've heard people say their breakfast tastes better after brushing theire teeth. I've never experienced bad taste from not brushing. I only care about the hygiene reasons for brushing in the morning.

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Just from an efficiency standpoint, you'd do best to wait till after breakfast, wouldn't you? But a lot of folks suffer from "morning breath"... A kind of overnight buildup of...Whatever that's rather unpleasant. So... Lots of folks do the first-thing brushing ritual. I've never bothered.... –  M. Werner Apr 21 '11 at 2:02
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You are meant to brush after breakfast, not before. My wife does this as well and I tell her it is pointless, brush after. And if you are a dentist, brush after lunch as well. –  Craig Apr 21 '11 at 2:02
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Also, I think the thing with brushing before breakfast started because so many people eat out for breakfast or while running out the door to work. In the 'good old days' people would sit down for breakfast at home. –  Craig Apr 21 '11 at 2:04
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@BlueRaja From a UK dentists’ pamphlet: “You don’t have to floss all of your teeth – just the ones you want to keep.” –  Konrad Rudolph Apr 21 '11 at 10:07
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In addition to the other answers, not disputing them but I don't want to add on to them, there is a coating applied from toothpaste that protects your teeth from subsequent bacterial infection. There are antibiotic agents in toothpaste to protect the toothpaste itself from spoilage but also inhibit growth on the teeth themselves. This is manifested by a slipperiness you can feel. –  geoO Mar 26 '13 at 0:59

2 Answers 2

up vote 34 down vote accepted

Brushing at night is the most important. Saliva naturally fights the growth of bacteria on your teeth. Your mouth dries out at night and reduces your mouths ability to do this. Ideally you would keep your teeth clean at all times but thats of course not realistic. A while back I read many websites and opinions about this very question. The main consensus seemed to be that people brush in the morning because it makes them feel good to start their day with a clean mouth (not because it's the best time to do it).

Here is a discussion about it:

During the day, you're flapping your jaw, drinking water, chewing gum, and moving your tounge, all of which help to clean things off of your teeth. At night, your mouth is much less active, which allows bacteria more time to grow without being mechanicalyl sloughed off.

Many years ago my orthodontist told me that it was most important to brush your teeth before going to sleep (I guess either for the night, or for a nap). Saliva production is down, and if you happen to sleep with your mouth gaping open, your teeth dry out and don't have that protective layer of saliva. Just the lack of movement of your lips and tongue while sleeping gives decay more of an opportunity to do its dirty work.

Here is a blog by a Dr:

Brushing before meals: Most people normally brush their teeth in the morning before breakfast. That is beneficial, as you have reduced the number of bacteria before exposing them to food. The amount of acid production is expected to be less, and so would be the damage to the teeth. You get an additional benefit if you use fluoride tooth paste, as the fluoride gets incorporated into the enamel and makes it strong and resistant to the effect of acid. (Fluoride converts the hydroxyl-apatite of enamel to calcium fluor-apatite).

@M.W If you are going to brush in the morning, it may actually be better to brush before you eat rather than after.

brushing right after eating is not at all advised, as the acid produced [by bacteria] has already begun the process of eroding enamel. If you brush promptly after a meal, you rub off part of the dissolved minerals of the enamel.

Edit:

@Craig, listen to your wife. She is correct in this case.

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Brushing teeth is a medical intervention. Medical interventions generally need controlled studies to be accepted. Your post simply lists a bunch of pseudoscientific discussion. Could you provide real sources? –  Christian Apr 21 '11 at 13:16
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I agree that brushing at night is most important, though the next sentence is BS:"your teeth dry out and don't have that protective layer of saliva" since bacteria can't live in a dry environment. Having completely dry teeth would actually be a very effective way to keep them from rotting. –  ufotds Aug 17 '11 at 10:43
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A web forum discussion and a link to a blog from an institute that develops "mind power" are not good sources. Would you be willing to back this up with proper sources? –  neilfein Oct 31 '11 at 1:13
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I am so confused about why this post has upvotes...Isn't this the type of post we want to downvote? –  Jase Dec 26 '12 at 2:13
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Weak, I'm downvoting for poor sources. OOps, can't, not enough rep. –  geoO Mar 26 '13 at 0:59

Expanding on Logicbird's answer, here is what the British Dental Health Foundation says:

Acidic foods and drinks, such as oranges, grapefruit and fruit juices that are often eaten at breakfast time, soften the enamel on your teeth.

Brushing immediately afterward wears the enamel away, and can cause dental erosion, which may lead to pain and extreme sensitivity in the teeth, and also lead to cosmetic problems.

The saliva in your mouth neutralises the acidity and restores its natural balance. However research has shown that this can take up to an hour.


Their tips for avoiding dental erosion are:

  • brush teeth before breakfast if you have fruit or fruit juice, or

  • wait one hour after eating or drinking anything acidic before
    brushing

  • use a straw when drinking acidic drinks to reduce contact with teeth

  • drink water and milk between meals in preference to juice and fizzy drinks

  • chew sugar-free gum - this will produce more saliva to help cancel
    out acid in your mouth

  • finish a meal with cheese or milk to help neutralise any acids


The NHS says the same:

Brush your teeth in the morning before breakfast and last thing at night before you go to bed (and ideally at least an hour after your evening meal).

Brushing your teeth straight after a meal can damage your teeth, especially if you've had fruit, fizzy drinks, wine or any other food that contains acid. This is because tooth enamel is softened by the acid and can be worn away by brushing. Waiting an hour gives your saliva chance to neutralise the acid.

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If I brush my teeth before I drink an acidic juice, that means there's little plaque or saliva to prevent the juice from breaking down the enamel. So why brush before drinking? –  JoJo Apr 21 '11 at 22:13
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@JoJo - Brushing actually induces salivary secretion –  Oliver_C Apr 22 '11 at 9:24
    
It says here at one point enamel get softer. Does that means that it gets harder again if you leave it alone or...? –  user5957 Feb 1 '12 at 22:41
    
@Amer - My dentist said that fluoride (e.g. in toothpaste) would help harden it. –  ChrisW Feb 2 '12 at 0:43
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@Amer - Here is a study saying: Rehardening effects following milk or saliva exposures respectively were evident, presumably due to deposited organic and mineral material on the enamel surface. –  Oliver_C Feb 3 '12 at 15:17

protected by Oddthinking Feb 10 '13 at 10:11

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