Why do we develop bad breath while fasting?
S. Narasimhan, Chennai
Bad breath is also known as halitosis or fetor oris. Foulness of breath is a social menace. Many people are not aware that their breath is foul. Though it is found more commonly in the elderly it is quite common among youngsters also.
Friends and others who come into contact with the sufferer hesitate to apprise him of the condition for fear of hurting his sentiments. Some people believe that it is incurable!
Bad breath usually results from periodontal diseases – disease of the gums and other structures supporting teeth, ill-fitting dentures, carious teeth, poor oral hygiene, metabolic activity of bacteria in plaque or putrefaction of sulfide-yielding food (proteins), etc.
Contributory factors are smoking, alcohol, sinusitis, lung disease and less commonly diseases of the esophagus.
Locally retained bacteria metabolize sulfur-containing amino acids (cysteine, methionine) in protein to yield volatile hydrogen sulfide and methyl mercaptane.
These gases have foul smell. Not only do they stink but they also damage the surrounding tissue. Thus they perpetuate bacterial retention and periodontal disease. At night and between meals conditions are optimal for odor production.
That is one reason why we develop bad breath while fasting. So eating regularly may help prevent bad breath. (Breath fresheners may help). Some people advise brushing the tongue, a practice common in India. Periodic scaling will, of course, help.
Prolonged fasting may cause a condition called Ketosis. This is from burning of too much fat. Ketosis does not result from just overnight fasting. Fasting has to be longer than that to give rise to ketosis.
The body has enough glucose stored as glycogen to see it through about 24 hours. Beyond that it relies on its fat reserves. All the fat that is mobilized is not burnt in the final common pathway of metabolism — the citric acid cycle. The excess fatty acid — acetic acid — gets diverted to the pathway for the formation of ‘ketone bodies', a product of fat metabolism.
They are formed in the liver and used by peripheral tissues.
When the rate of synthesis exceeds the metabolic capacity of tissues, ketonemia (presence of more than normal amount of ketones in blood) and ketonuria (presence of ketones in urine), together called ketosis, result.
In ketosis, ketone bodies are excreted in breath causing ‘bad breath'.
The breath has a characteristic smell described in medical circles as ‘ fruity'. While this smell is not normal it can not be described exactly as ‘foul' either. This smell is often encountered in diabetics.
Physician
Irinjalakuda
Thrissur, Kerala
