Magnesium Intake Calculator

The NIH recommends: men 19-30 years: 400 mg/day; men 31+ years: 420 mg/day; women 19-30 years: 310 mg/day; women 31+ years: 320 mg/day; pregnant women: 350-360 mg/day; breastfeeding women: 310-320 mg/day. Children need 80-240 mg/day depending on age. Most Americans do not meet the RDA from food alone.

Magnesium is involved in over 300 enzyme reactions. It is essential for energy production (ATP synthesis), protein synthesis, muscle and nerve function, blood glucose regulation, blood pressure regulation, and bone development. About 60% of the body's magnesium is in bones. Low magnesium is linked to type 2 diabetes, heart disease, and migraines.

Pumpkin seeds top the list at 156 mg per oz. Chia seeds provide 111 mg per oz. Almonds, cashews, and peanuts provide 60-82 mg per oz. Spinach provides 78 mg per half cup cooked. Black beans, edamame, and avocado are good plant-based sources. Dark chocolate (70-85%) provides about 65 mg per oz. Fish, chicken, and beef provide modest amounts.

The tolerable upper intake level (UL) for supplemental magnesium is 350 mg/day for adults (not including food sources). Excess supplemental magnesium causes diarrhoea, nausea, and cramps. Very high doses from supplements can cause low blood pressure, irregular heartbeat, and in extreme cases respiratory arrest. The UL does not apply to magnesium from food.

Some evidence suggests magnesium supplements may improve sleep quality, particularly in older adults and people with low magnesium levels. Magnesium regulates neurotransmitters and melatonin. However, the evidence is modest. The NIH notes that more research is needed. If you are considering magnesium supplements for sleep, discuss with your healthcare provider first.