A long-running health survey of American adults is, for the first time, now able to include valuable information about our taste and smell functions, thanks to support from the National Institute on Deafness and Other Communication Disorders (NIDCD).
By Robin Latham, NIDCD
For more than 60 years, a national survey of American adults has been gathering information on a wide range of health factors and conditions. The exam includes the usual types of tests you find in a standard physical exam: height, weight, blood pressure, and cholesterol levels. But it also includes a nutrition survey using sample size bowls, plates, and cups to help people accurately describe what and how much they eat. In a separate home visit, researchers document day-to-day activities, lifestyle behaviors, illness symptoms, and chronic health conditions.
The ongoing survey is called the National Health and Nutrition Examination Survey (NHANES). It is the only national U.S. health survey that combines both in-person interviews with physical examinations.
In the recent past, thanks to NHANES' careful collection of health and health behavior data, scientists have been able to substantiate the dangers of second-hand cigarette smoke, and the health consequences of exposure to lead-based paint. NHANES' data built the growth charts your pediatrician uses to determine how well your baby is developing, compared to other babies of the same age.
Although NHANES had included a hearing test for decades, the NIDCD has been trying to add assessments for taste and smell function since 1997, when it first began working with the National Center for Health Statistics (NCHS) to develop reliable tests. NCHS is now part of the Centers for Disease Control and Prevention (CDC), which runs NHANES.
"Taste and smell form the basis for what we choose to eat or drink," says Howard Hoffman, M.A., program director of epidemiology and statistics at the NIDCD, and one of the prime movers of the drive to include taste and smell tests in NHANES. "Does the ability to taste and smell impact nutrition? I would say so, but in what ways and to what degree remains uncertain."
By adding tests that measure taste and smell function to the nutritional information NHANES already collects, epidemiologists and biomedical researchers will be able to take a closer look at the role of taste and smell in nutrition and health. Just as important, thanks to the physical exams and detailed medical histories NHANES technicians collect, researchers will be able to explore associations between taste and smell dysfunction and medical conditions such as high blood pressure and diabetes, as well as brain disorders such as Parkinson's and Alzheimer's diseases, which are characterized by an early loss of smell.