deficiency
Meaning of deficiency: Deficiency describes an insufficient amount of a substance the body needs, such as a vitamin, mineral, or hormone, to function normally.
Definition of deficiency
Deficiency describes a condition in which the body has less than the amount it needs of a particular substance required for normal function, such as a vitamin, mineral, hormone, enzyme, or other essential compound. A deficiency can develop for many different reasons, including inadequate dietary intake, poor absorption within the digestive tract, increased loss from the body, or an inherited condition affecting how a substance is produced or used.
The effects of a deficiency depend entirely on the substance involved and the role it normally plays in the body, ranging from very mild or unnoticeable effects to significant impairment of a body system, and symptoms can take time to appear as the body's existing reserves of the substance are gradually used up. Some deficiencies affect a single body system, while others have wide ranging effects because the deficient substance is involved in many different processes throughout the body.
Diagnosing a specific deficiency generally involves laboratory testing that measures the level of the substance in question, often alongside an assessment of diet, absorption, and other possible contributing factors.
Used in a sentence
Laboratory testing confirmed a vitamin D deficiency in the patient reporting persistent fatigue.
Good to know
Symptoms of a deficiency often appear only after the body's existing reserves of the substance have been gradually depleted, so a deficiency can be present for some time before it becomes clinically apparent.
Word origin
Where “deficiency” comes from
Formed from Latin deficere, meaning to fail or be lacking, from de- and facere, meaning to do or make.