![]() |
Magnesium in diet
Definition
Magnesium is an essential mineral for human nutrition.
Alternative Names
Diet - magnesium
Function
Magnesium in the body serves several important functions:
- Contraction and relaxation of muscles
- Function of certain enzymes in the body
- Production and transport of energy
- Production of protein
Food Sources
Most dietary magnesium comes from vegetables, such as dark green, leafy vegetables. Other foods that are good sources of magnesium:
- Fruits or vegetables (such as bananas, dried apricots, and avocados)
- Nuts (such as almonds and cashews)
- Peas and beans (legumes), seeds
- Soy products (such as soy flour and tofu)
- Whole grains (such as brown rice and millet)
Side Effects
Side effects from increased magnesium intake are not common because the body removes excess amounts. Magnesium excess almost always occurs only when magnesium is supplemented as a medication.
Lack of magnesium (deficiency) is rare. The symptoms include:
- Hyperexcitability
- Muscle weakness
- Sleepiness
Deficiency of magnesium can occur in people who abuse alcohol or in those who absorb less magnesium due to:
- Burns
- Certain medications
- Low blood levels of calcium
- Problems absorbing nutrients from the intestinal tract (malabsorption)
- Surgery
Symptoms due to a lack of magnesium have three categories.
Early symptoms:
- Anorexia
- Apathy
- Confusion
- Fatigue
- Insomnia
- Irritability
- Muscle twitching
- Poor memory
- Reduced ability to learn
Moderate deficiency symptoms:
- Heart (cardiovascular) changes
- Rapid heartbeat
Severe deficiency:
- Continued muscle contraction
- Delirium
- Numbness
- Seeing or hearing things that aren't there (hallucinations)
- Tingling
Recommendations
These are the recommended daily requirements of magnesium:
- Children
- 1 - 3 years old: 80 milligrams
- 4 - 8 years old: 130 milligrams
- 9 - 13 years old: 240 milligrams
- 14 - 18 years old (boys): 410 milligrams
- 14 - 18 years old (girls): 360 milligrams
- Adult females: 310 - 320 milligrams
- Pregnancy: 350 - 400 milligrams
- Breastfeeding women: 310 - 360 milligrams
- Adult males: 400 - 420 milligrams
References
Food and Nutrition Board, Institute of Medicine. DRI Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington, DC: National Academy Press; 1997.
Yu ASL. Disorders of magnesium and phosphorus. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 120.
Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.
Reviewed By: Linda Vorvick, MD, Family Physician, Seattle Site Coordinator, Lecturer, Pathophysiology, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
| A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch). |

