The Dangers and Safety Precautions Related to the Olfactory Dysfunction Anosmia
Imagine the smell of some freshly baked cookies hot out of the oven, or the clean smell of a brand new car's interior. Have you ever thought what it might be like to never smell these scents again? What if you could not smell your dinner burning on the stove or the fact that the baby needs a diaper change? The National Institutes of Health in 1979 found that around 200,000 people consult their doctors every year for the decreased or total loss of smell (Crawford and Sounder, 95). The disorder is anosmia, the loss of the sense of smell, usually from a sinus infection or a nasal obstruction, which lasts only temporarily. Anosmia is also known as a permanent condition commonly resulting from a head injury or disease, such as airopic rhinitis or chronic rhititus associated with granulomatous disease, which destroys either the olfactory
nerve. This smell disorder can also be caused by psychological factors, such as a specific fear of a particular smell (Mosby, 94).
Of then five senses, smell seems to be the least appreciated (Gillyatt, 97). Society always gives attention to the senses that appear most necessary: sight and hearing. Touch and taste appear more important because it is obvious that without them life becomes more challenging (Gillyatt, 97). Humans are microsmatic, which means that the sense of smell is not necessary for survival like with animals (Goldstein, 99). The sense of smell can protect people and therefore is important. Smell also makes things enjoyable (Gillyatt, 97). For instance, when eating a favorite food the taste is much more flavorful when feeling healthy opposed to being congested. Humans can recognize as many as 10,000 different scents, compared to the sense of taste , which is limited to four basic categories: sweet, salty, sour, and bitter (Gillyatt, 97). The sense of smell is very important, but taken for granted. Everyone should be aware of anosmia because as people age the disorder becomes more and more common. Approximately fifty percent of people over 65 years of age have experienced a decrease in smell (Schiffman, 94). It is apparent that the weakening of the sense of smell is age related (Cain and Stevens, 86). Anosmia is a disorder that needs to be taken seriously. The permanent loss of smell can be hazardous to ones health if not dealt with properly.
Recently, it has been discovered that odors that are sensed simultaneously are identified individually and consecutively in the brain, instead of as a mixed odor. Nagel observed that odor combinations are similar to combinations of color, rather than sound (JAMA, 98). The sense of smell is very complex. Millions of odor receptors work to identify different scents. The brain sorts the hundreds of signals representing specific odors into round files called glomeruli. The glomeruli are a major part of organizing scent perception (Richardson, 95). These glomeruli line the olfactory bulbs which are connected to olfactory nerves and olfactory tract, the parts of he brain associated with the sense of smell (Mosby, 94). Airflow patterns in the nose allow for scents to reach the olfactory receptor cells located on the dorsal side of the nasal cavity, septum, and superior tubinates. These cells are constantly renewing, which takes about one month. People with olfactory dysfunction
have damaged some of their olfactory nerves. Age-related anosmia is usually due to degeneration of the gloneruli and olfactory bulb (Schiffman, 97).
Health can be greatly affected when a person has anosmia. Taste is most commonly lost with the disorder since there is a close connection of smell and flavor (Goldstein, 99). Because anosmia results from an olfactory deficit, there is usually a loss of taste. A taste loss is one of the first things noticed by people losing their sense smell. This loss of taste can greatly affect a person's eating habits. Many people with anosmia are known to skip meals because the appeal for food is not there. Nothing seems to taste good anymore and the flavor is gone. Another reason appetite is effected, is that the aroma of foods does not cause a desire for food because the person cannot detect the luring odors from the food (Crawford and Sounder, 95). Not eating results in malnutrition and involuntary weight loss. This can also lead to illness because the proper foods are not being eaten to keep a person healthy. The primary reinforcers for eating are saticity and pleasure. Without taste and smell the person will not experience these sensations (Schiffman, 97). Anosmia can also have the opposite effect and cause a person to overeat to compensate for the loss of taste. This can result in a weight problem (Crawford and Sounder, 95). Obesity is a major result of elderly women with olfactory dysfunction's (Duffy, Backstrand, and Ferris, 95).
A study was conducted in 1995 analyzing smell disorders and how they effect nutrition of elderly women. Eighty women were studied for odor perception and odor identification using the standard olfactory test from the study by Cain, Gent, Goodspeed, and Leonard. Almost half of the women had problematic risks concerning minimal interest in food related activities, minimal preference for foods with sour/bitter tastes, higher intake of sweets and less intake of low-fat milk products ( Duffy ,Backstrand, and Ferris, 95) The solution to these eating disorders is to find ways to make eating enjoyable again. The texture of food and how they are combined become very important to someone with anosmia. Eating a hot meal with a cold salad allows for different temperature experiences and when eating vegetables, mixing partially cooked vegetables with fully cooked ones allows for a texture comparison. Another suggestion is to eat spicy foods that cause sensations on the tongue (Crawford and Souder, 95). The object is to take some time to make meals interesting and fun, so there is still an appeal to eat and feel satisfied.
The sense of smell is not only important to taste, but it is also essential for detecting signs of danger such as smoke, gas leaks and spoiled food. A person living with anosmia needs to take extra safety precautions
. Smoke detectors are a necessity in all areas of the home, especially in the kitchen and near fireplaces (Gillyatt, 97). An extra safety is having fire extinguishers in case of a small fire (Crawford and Sounder, 95). Another safety precaution is electric stoves instead of gas stoves. Gas leaks are recognizable by smell and could not be detected by someone with this disorder (Gillyatt, 97). Household cleaners can be a risk factor because the odor of the chemicals will not be noticed to warn the person that the chemicals are toxic and should be used in a well- ventilated area. Warning labels should be read as a reminder of the chemicals involved in such things as hair products, bathroom and kitchen cleaners, insecticides, etc. Our sense of smell keeps people aware of automotive troubles. Regular checkups should occur to prevent problems. The sense of smell is also very important in detecting spoiled food. To prevent this leftovers need to be marked with throwaway dates and special attention needs to be given for freshness dates to be sure the food is good and safe to eat (Crawford and Sounder, 95).
Some people are more likely to have olfactory deficits. People, ages 65 and over, commonly experience progressive impairment in both taste and smell. The proportion and population of the elderly is constantly increasing and they are experiencing age related sensory loss. The most publicized sensory loss of the elderly has been sight and hearing. There has not been much attention or research done regarding the loss of smell. The main cause of olfactory loss is normal aging. Diseases, medications, surgical intervention and environmental exposure can also be related. One study found a relation with seizures and smell disorders. Patients who had suffered from two types of seizures, mesial temporal lobe and neocortical, were studied to see if testing olfactory functions is useful to distinguish between the two seizures. The results found that mesial temporal lobe seizures impaired olfactory quality discrimination and resulted in lower delayed recognition scores than neocortical seizures (Savic, 97). These results imply that the seizures affect different parts of the brain, and that the many different aspects of are sense of smell can be impaired without complete damage.
Anosmia with the elderly can be a real problem. Many elderly people live in nursing homes. This is a situation where a person with anosmia may tire of the food because it is bland to them. Eating becomes boring and can cause a person to not eat, which can lead to weight loss. Younger individuals are able to distinguish the degrees of difference between odors of different quality much better than an elderly person is. The difficulty of identifying odors becomes very common once over the age of 80 (Schiffman, 94). One study that supports the age-related olfactory loss also found that both men and women's sense of smell decrease with old age, but women did significantly better than the men when using Pennsylvania's Smell Identification Test (Brant, Cruise, Metter, Pearson, and Ship, 96). The topic of anosmia is growing. More and more people have become aware of this disorder in the past few years. Today's sense of smell is mostly for practical purposes when compared to the early stages of the evolution (JAMA, 98) but, it should not be taken for granted. Medical research will hopefully discover ways to rehabilitate the sense of smell when it is lost so meals can always be enjoyed, healthy living practical, and everyone can live safer.
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