(HealthDay News) -- A food's flavor is produced by a combination of your senses of taste and smell. If you begin to lose the ability to distinguish foods that are sweet, salty, sour or bitter, a number of factors could be at fault.

The University of Maryland Medical Center offers these possible causes for impaired taste:

• Getting older.
• Having Bell's palsy.
• Having the gum disease gingivitis.
• Having a cold or the flu, a nasal or salivary gland infection, sinusitis or nasal polyps.
• Being a heavy smoker.
• Having dry mouth.
• Having an injury to the head, nose or mouth.
• Having pharyngitis, an inflammation of the pharynx.
• Having a side effect of certain medications.
• Having a vitamin deficiency.