Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Deficiency
Introduction
Overview
A deficiency is a lack of something.
- In mathematics, a deficient number is a number n for which σ(n) < 2n.
- In medicine there are a variety of nutrient deficiencies:
- Avitaminosis is a deficiency of vitamins.
- Boron deficiency (medicine)
- Chromium deficiency
- Iron deficiency (medicine)
- Iodine deficiency
- Magnesium deficiency (medicine)
- In genetics, a genetic deletion is also called a deficiency.