Will Taking Too Much Magnesium Cause a Zinc Deficiency?

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Once they enter your body, vitamins and minerals in the foods and supplements you consume can interact with each other, and these interactions can alter the absorption of these nutrients in your digestive tract. One such interaction occurs between magnesium and zinc. Too much magnesium does not cause a zinc deficiency. However, the reverse is true, and high doses of zinc can cause a magnesium deficiency.

Magnesium and Zinc Interaction

Magnesium and zinc can interact in your digestive tract, which can affect your body's ability to absorb the nutrients. Specifically, taking large amounts of zinc can disrupt normal magnesium absorption. As a result, take a zinc supplement along with a meal might prevent your body from effectively absorbing the magnesium from your food. However, your kidneys still excrete magnesium in your urine, and without the ability to replenish your magnesium stores from your diet, you might develop a magnesium deficiency.


Effect of Magnesium Depletion

Magnesium depletion due to zinc supplementation can negative affect your health. The mineral contributes to nerve, muscle and cardiovascular function, so a magnesium deficiency can affect all these tissues. You might notice muscle weakness, fatigue or headaches due to low blood pressure and anxiety. The deficiency can also disrupt your normal heart rhythm, and can cause serious health conditions like seizures.

Zinc Toxicity

Taking doses of zinc large enough to inhibit magnesium absorption might also cause other health effects due to zinc toxicity. High doses of zinc can cause nausea and vomiting, as well as abdominal cramping and loose stool. A zinc overdose can also cause additional mineral imbalances, depleting your body's copper stores and causing a copper deficiency. The excess zinc might also have an effect on medication in your system, increasing your risk of drug side effects.


Zinc Intake and Considerations

Consuming more than 142 mg of zinc daily proves sufficient to alter the magnesium balance and prevent magnesium absorption in men, according to the Linus Pauling Institute at Oregon State University. This zinc dose is much larger than your required intake: adult men require only 11 mg daily, while women require 8 mg. If you take supplements containing zinc, visit a doctor to determine an appropriate dosage to prevent a magnesium deficiency. Never combine supplements without your physician's approval, and only take supplements as recommended by your doctor.