Hygiene is often defined on subjective metrics. Most natural practices are termed unhygienic simply because of the disgust people feel towards them. Disgust is subjective; and if hygiene is based on disgust, what is unhygienic to some can be hygienic to others, thus creating inconsistent definitions.

It is improper to have inconsistent definitions, especially in the affairs of health. Therefore, a better way to look at hygiene is on the basis health consequences, which is rather an objective metric. Practices that result in bad health should be termed unhygienic, and those that do not result so, however disgusting it seems to a person, must not be termed unhygienic.