The odor from our mouths are caused by the waist from bacteria that live in our mouths. These waists are volotile (rapid evaporation) sulfides. With the reproduction of extra bacteria in our mouths, or the consumption of much protein foods, will result in more than normal amount of emitting sulfides. I do not know of any test. What I do know is that in most cases, halitosis do increase with stress. This might be because stress do deplete the immune system and thus would cause an increase in bacterial reproduction. This no doubt includes mouth bacteria. Other reasons for bad breath are toxic digestive system, gum disease, tooth decay, heavy metal buildup, nose or throat infection, improper diet, constipation, smoking, diabetes, indigestion, inadequate protein digestion, liver malfunction, postnasal drip, and poor oral hygiene. If you are living in a stressful situation, then do all you can to reduce or eliminate the stress. As soon as the stress is gone, the bad breath will also. Learning to take things as they come and work with it, is a good way of reducing the effect of stress. Drink pure water on a regular basis. This seem to help a lot. Have your colon cleanse at least four times per year. (use a cleanser that carries probiotic to be taken after the cleanse is finished.) While it is important to have meat in your diet, eating lots of meats can result in clogs which in turn can cause bad breath. Also protein residue forms food for mouth bacteria. Eat lots of raw fruits and raw vegetables. These will help with regular bowel action, which will in turn discourage the storage of toxic waste. Raw foods also supply vital nutrients that are very important for the boosting of your immune system. Brush and floss your teeth every day and visit your dentist once or twice every year. Also gargle every day. Using a breath spray or a mouth wash do help. Ask a trusted friend to tell you when your breath is smelly. That is what I do. Or use a spoon to scrape the back of your tongue and smell it. The following links will give you more detailed information about bad breath. http://www.animated-teeth.com/bad_breath/t3_causes_of_halitosis.htm http://www.animated-teeth.com/bad_breath/t1_halitosis.htm