In
medicine
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pr ...
, a deficiency is a lack or shortage of a functional entity, by less than normal or necessary supply or function.
TheFreeDictionary > deficiency
Citing:
*Dorland's Medical Dictionary for Health Consumers. © 2007
* Miller-Keane Encyclopedia & Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. 2003
Nutrients
Malnutrition
Malnutrition occurs when an organism gets too few or too many nutrients, resulting in health problems. Specifically, it is "a deficiency, excess, or imbalance of energy, protein and other nutrients" which adversely affects the body's tissues ...
can cause various effects by deficiency of one or more nutrients. For example, vitamin A deficiency causes symptoms such as xerophthalmia (dry eyes) and night blindness.
Endogenously produced proteins
Deficiencies of endogenously produced proteins such as enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
s are the underlying mechanisms of almost all genetic disorder
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders ...
s, for example the inborn errors of metabolism
Inborn errors of metabolism form a large class of genetic diseases involving congenital disorders of enzyme activities. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances ( substra ...
.
See also
* Complement deficiency
References
Medical terminology
Human diseases and disorders
{{disease-stub