The result is that the blood glucose level rises somewhat after eating, and within an hour or so, returns to the normal fasting level. Even the best diabetic treatment with synthetic human insulin or even insulin analogs, however administered, falls far short of normal glucose control in the non-diabetic.Complicating matters is that the composition of the food eaten (see glycemic index) affects intestinal absorption rates. Glucose from some foods is absorbed more (or less) rapidly than the same amount of glucose in other foods. In addition, fats and proteins cause delays in absorption of glucose from carbohydrates eaten at the same time. As well, exercise reduces the need for insulin even when all other factors remain the same, since working muscle has some ability to take up glucose without the help of insulin.Because of the complex and interacting factors, it is, in principle, impossible to know for certain how much insulin (and which type) is needed to cover a particular meal to achieve a reasonable blood glucose level within an hour or two after eating. Non-diabetics beta cells routinely and automatically manage this by continual glucose level monitoring and insulin release. All such decisions by a diabetic must be based on experience and training (i.e., at the direction of a physician, PA, or in some places a specialist diabetic educator) and, further, specifically based on the individual experience of the person. But it is not straightforward and should never be done by habit or routine.
Occasionally, BHT may be caused by the use of antimicrobial medications (e.g., tetracyclines), or oxidizing mouthwashes or antacids. A soft diet may be involved as normally food has an abrasive action on the tongue, which keeps the filiform papillae short. Pellagra, a condition caused by niacin (vitamin B3) deficiency, may cause a thick greyish fur to develop on the dorsal tongue, along with other oral signs.Transient surface discoloration of the tongue and other soft tissues in the mouth can occur in the absence of hairy tongue. Causes include smoking (or betel chewing), some foods and beverages (e.g., coffee, tea or liquorice), and certain medications (e.g., chlorhexidine, iron salts, or bismuth subsalicylate (Pepto-Bismol)). Diagnosis
Diagnosis is usually made on the clinical appearance without the need for a tissue biopsy. However, when biopsies have been taken, the histologic appearance is one of marked elongation and hyperparakeratosis of the filiform papillae and numerous bacteria growing on the epithelial surface.Hairy tongue may be confused with hairy leukoplakia, however the latter usually occurs on the sides of the tongue and is associated with an opportunistic infection with Epstein–Barr virus on a background immunocompromise (almost always human immunodeficiency virus infection but rarely other conditions which suppress the immune system). Classification
Hairy tongue (lingua villosa) refers to a marked accumulation of keratin on the filiform papillae on the dorsal surface of the tongue, giving a hair-like appearance. Black tongue (lingua nigra) refers to a black discoloration of the tongue, which may or may not be associated with hairy tongue.