Magnesium Forms

The article claims magnesium oxide has about 4% absorption, so a 400 mg tablet provides only about 16 mg absorbed magnesium. Different magnesium salt forms are not interchangeable and can have different physiological effects. The article prefers magnesium glycinate because it absorbs much better than oxide and avoids oxide-associated GI distress. Most magnesium forms other than threonate may be suitable for nighttime use, particularly those intended for relaxation or muscle relaxation. The article states that glycine in magnesium glycinate may support sleep and reduce neural excitability through GABA receptor activity. The article says higher magnesium oxide intake can cause diarrhea, cramping, and GI distress because unabsorbed magnesium draws water into the intestines. The article says magnesium oxide is common because it is inexpensive and compact. The article limits magnesium oxide use to short-term treatment of severe constipation. Magnesium glycinate, citrate, and nitrate are associated with relaxation, muscle relaxation, and mood relaxation, making them suitable for later-day use.