If you have a poor sense of smell you will not detect the presence of leaking gas in the home or service station, or the smell of other poisonous gases like chlorine and the foul-smelling rotten egg gas, which can be emitted at dangerous levels from swamp lands or marshes.
Poor sensitivity also means that you will perceive the flavour of foods differently to other people. For example, if you cannot detect orange, apple or strawberry smells, these fruits will have little flavour and be bland. Similarly, if you cannot perceive the basic tastes of sweet, salty, sour, bitter and umami – the savoury taste of monosodium glutamate in many Asian dishes – food will be perceived as bland and unpleasant.
Changes to the flavour of food and beverages as a result of smell or taste loss can have significant effects on health and result in inadequate nutrition, anorexia or obesity. These serious outcomes arise because people find it difficult to adjust to their new world of unpleasant foods. Some people, however, continue to eat normally, and there is some evidence that these individuals can imagine flavours.
Loss of smell or taste can be due to diseases, head injuries, medications, or people can be born smell-blind or taste-blind. Often loss of these senses is temporary and may last up to a year or two.
Fortunately, unlike the senses of vision and hearing...