Deficiency/Heart/Sleep

Magnesium

Essential mineral that corrects low intake and may support sleep and blood pressure in adults who do not get enough from food.

Magnesium

Essential mineral that corrects low intake and may support sleep and blood pressure in adults who do not get enough from food.

score

evidence

Caution

risk

Proven Benefits

01Corrects magnesium deficiency

02Lowers blood pressure modestly

03Improves sleep quality

04May improve endothelial function

05May reduce nighttime leg cramps

06May support normal heart rhythm

Chemical Forms

Recommended

Magnesium glycinate
Magnesium citrate
Magnesium chloride
Magnesium malate

Avoid

Magnesium oxide (poorly absorbed, more likely to cause diarrhea)
Magnesium hydroxide (better as a laxative/antacid than for daily repletion)

Expert Note

Glycinate, citrate, and chloride are generally better absorbed and better tolerated than oxide. Glycinate is usually gentler on the gut, citrate absorbs well but can loosen stools, and chloride is well absorbed in capsules or liquids. Oxide has a high elemental percentage on the label but poor solubility, so it often acts more like a laxative than a reliable repletion form.

Protocol

Amount

200-350 mg elemental magnesium

Frequency

Once daily or split into 2 doses

When

With food if GI-sensitive; evening can help if your goal is sleep, but consistency matters more than timing.

Condition-Based Dosing

Low dietary intake / general repletion

200-300 mg elemental magnesium daily— Start lower if you are prone to loose stools; glycinate is usually best tolerated.

Poor sleep quality or nighttime muscle cramps

200-350 mg elemental magnesium in the evening for 2-4 weeks— Glycinate is often preferred because it is gentler on the gut.

Long-term proton pump inhibitor use or adults 60+

200-350 mg elemental magnesium daily— Consider checking serum magnesium if symptoms, prior low levels, or long-term use are present.

Safety & Limits

Upper Safe Limit

350 mg/day from supplements (IOM UL for adults; higher intakes mainly raise diarrhea risk)

Cycling

Safe for continuous use

Contraindications

Significant kidney disease or dialysis without clinician guidance — reduced magnesium excretion can raise hypermagnesemia risk

Tetracycline or fluoroquinolone antibiotics — magnesium binds the drug and lowers absorption; separate by several hours

Levothyroxine — magnesium can reduce drug absorption; separate by at least 4 hours

Bisphosphonates like alendronate — magnesium reduces absorption; separate by at least 2 hours

Myasthenia gravis — magnesium can worsen muscle weakness, especially at higher intakes

Synergies

Vitamin D3

Magnesium is a cofactor for vitamin D activation and signaling, so low magnesium can blunt the response to D3 supplementation.

Potassium

Magnesium supports Na/K-ATPase activity, and low magnesium can make low potassium harder to correct and may worsen blood pressure or rhythm issues.

Avoid Combining With

✕Proton pump inhibitors like omeprazole (reduce intestinal magnesium absorption long-term)
✕Chronic alcohol use (increases urinary magnesium loss)
✕Large calcium doses taken together (possible absorption competition; separate by 2+ hours)
✕High-phytate fiber supplements taken at the same time (may modestly reduce absorption; separate by 1-2 hours)

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