Why is my breath bad in the morning?

Because the mouth does not get as much oxygen during the night hours and because it is largely inactive often your breath odour will be worse when you wake up in the morning.

How can I check my own breath?

You have probably realized how difficult it can be to smell your own breath. Blowing into cupped hands is not very accurate.
So here are two more methods:
•    Lick and smell the inside of your wrist – (although your skin does have a smell of its own as well)
•    Wipe a cotton bud, tongue scraper or teaspoon over the back of your tongue and smell

Why the back of my tongue?

The back of the tongue is a quiet relatively dry and inactive area of the mouth where anaerobic (not requiring oxygen) bacteria can thrive. Food debris, post nasal drip, and dead skin cells all create a lively environment of bacteria and can be one of the causes of bad breath.

Dry mouth and bad breath

A dry mouth can be the cause bad breath.
Certain substances can cause the mouth to dry out:
•    Alcohol
•    Coffee
•    MSG (Monosodium Glutamate – a common additive in some Asian cuisine)

Trapped food and bad breath

Food trapped in the interstices between your teeth can contribute to bad breath.

Sometimes gaps develop between your teeth near the gum but the teeth remain close together at the biting edge. Food can be forced up into the gap by the biting action but is not able to come back down on its own. This is called a food trap and debris can get trapped in here and cause breath odour.

If you think you have a food trap tell your dentist.

More serious causes of bad breath.

Sometimes the cause of persistent bad breath is more serious and is worth getting checked out:
•    Gum disease
•    Abscessed tooth
•    Xerotomia ( dry mouth due to more complex issues such as damaged saliva glands)