Many people turn to homeopathic(同種療法の、同毒両方の)remedies, including products containing zinc(亜鉛), to mitigate the effects of the common cold. However, a new study indicates that over-the-counter zinc gluconate(グルコン酸塩) nasal sprays are ineffective in preventing or reducing the duration of the common cold. Furthermore, the evidence suggests that these sprays can dull users' sense of smell or even eliminate it permanently. The loss of one's sense of smell, a condition called anosmia(無臭覚症), affects how sufferers experience food, hinders their ability to detect dangerous conditions like gas leaks or fires, and can even lead to feelings of depression.