Polyphagia

The word polyphagia (/ˌpɒliˈfeɪdʒiə/) uses combining forms of poly- + -phagia, from the Greek words πολύς (polys), "very much" or "many", and φαγῶ (phago), "eating" or "devouring".

Polyphagia is one of the most common symptoms of diabetes mellitus. It is associated with hyperthyroidism and endocrine diseases, e.g., Graves' disease, and it has also been noted in Prader-Willi syndrome and other genetic conditions caused by chromosomal anomalies. It is only one of several diagnostic criteria for bulimia and is not by itself classified as an eating disorder. As a symptom of Kleine–Levin syndrome, it is sometimes termed megaphagia.[4]

Knocking out vagal nerve receptors has been shown to cause hyperphagia.[5]

According to the National Center for Biomedical Information, polyphagia is found in the following conditions:[6]

• Chromosome 22q13 duplication syndrome
• Chromosome Xq26.3 duplication syndrome
• Congenital generalized lipodystrophy type 1
• Congenital generalized lipodystrophy type 2
• Diabetes mellitus type 1
• Familial renal glucosuria
• Frontotemporal dementia
• Frontotemporal dementia, ubiquitin-positive
• Graves' disease
• Hypotonia-cystinuria syndrome
• Kleine-Levin syndrome
• Leptin deficiency or dysfunction
• Leptin receptor deficiency
• Luscan-lumish syndrome
• Macrosomia adiposa congenita
• Mental retardation, autosomal dominant 1
• Obesity, hyperphagia, and developmental delay (OBHD)
• Pick's disease
• Prader-Willi syndrome
• Proopiomelanocortin deficiency
• Schaaf-yang syndrome

Diabetes mellitus causes a disruption in the body's ability to transfer glucose from food into energy. Intake of food causes glucose levels to rise without a corresponding increase in energy, which leads to a persistent sensation of hunger. Polyphagia usually occurs early in the course of diabetic ketoacidosis.[7] However, once insulin deficiency becomes more severe and ketoacidosis develops, appetite is suppressed.[8]

• Diseases and conditions associated with Polyphagia