What is the maximum daily dose of magnesium?

Magnesium is a mineral that is essential for health, but sometimes gets overlooked in discussions about healthy eating.

Studies find that because of changes in soil and a reduced intake of fruits and vegetables, we may not be getting enough magnesium to support our health.

Buying a magnesium supplement can be a shortcut to meeting shortfalls of your diet, but it doesn’t come without its own risks. There can be too much of a good thing.

Knowing what the appropriate amount of magnesium is for your body can help you stay healthy without experiencing bothersome side effects.

• What magnesium is
• Natural sources of magnesium
• What magnesium does for the body
• How much magnesium is normal
• How much is too much magnesium and associated side effects

Let’s dive into why magnesium is important, and how to get a proper amount into your diet daily.

Magnesium is naturally found in a variety of beverages, plant-based foods, and animal products. Plant-based foods containing fiber tend to have the most magnesium per serving.

Some sources of magnesium include:

• Nuts and seeds (e.g., pumpkin seeds, chia seeds, almonds, cashews)
• Leafy green vegetables (e.g., spinach)
• Legumes (e.g., peanuts, black beans, kidney beans, lentils)
• Whole grains (e.g., cereal, brown rice, oatmeal)
• Dairy and dairy alternatives (e.g., soymilk, yogurt, milk)

Manufacturers often add magnesium to refined grains, breakfast cereals, and other fortified foods to make up for the magnesium lost during processing.

Beverages like tea and coffee have magnesium but contain the compounds tannins and chlorogenic acid which can reduce how much of the mineral is actually absorbed into your body.

Drinking tap, bottled, or mineral water can give you some magnesium, but the amount of magnesium will differ depending on brand and water type.

As the fourth most abundant mineral in your body, magnesium is a part of a wide variety of physical functions.

These are just a few of the benefits that magnesium has:

The Food and Nutrition Board at the Institute of Medicine developed Dietary Reference Intakes to determine how much magnesium it would take to meet the nutrient needs of most healthy individuals.

The Recommended Dietary Allowances for magnesium in adults are:

• Men 19+ years: 400-420 mg/day
• Women 19+ years: 310-320 mg/day
  • During pregnancy, magnesium needs are increased to 350 -360 mg/day.

Health risks from magnesium usually occur from dietary supplements or medications that contain magnesium.

Common side effects from taking excessive magnesium include diarrhea, nausea, and abdominal cramping.

Getting a large amount of magnesium from food typically does not cause any side effects because your kidneys are usually able to eliminate extra magnesium from the body.

It is for this reason that the Tolerable Upper Limit for magnesium includes only daily magnesium from dietary supplements and medications.9

The Tolerable Upper Intake Levels (ULs) for supplemental magnesium is the same for men and women:

• 9-18 years: 350mg/day
• 19+ years: 350mg/day

Very large doses of magnesium from supplements or medications like antacids and laxatives can cause magnesium toxicity.10

Side effects of magnesium toxicity include low blood pressure, depression, nausea and vomiting, muscle weakness, irregular heartbeat, urine retention, and cardiac arrest.

To reduce the risk of getting too much magnesium, avoid stand alone magnesium supplements unless advised to do so by your healthcare provider. Eating a variety of nuts and seeds, legumes, whole grains, dairy and dairy alternatives, fruits and vegetables, and other nutrient-dense foods can help you meet your daily needs.

In the US, over half the population falls below daily requirements for magnesium according to the Dietary Guidelines for Americans. Other micronutrients that are under-consumed include vitamin D, vitamin E, vitamin C, vitamin A and calcium. A high quality multivitamin and mineral will provide approximately 100-200 mg of magnesium and fill the gaps for these other micronutrients.

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