Manganese vs. Magnesium: What's the Difference?

It can be easy to confuse the two minerals manganese and magnesium — their names sound so similar.

But manganese and magnesium are very different in many ways, including their composition, how they function in your body, their intake requirements as well as the symptoms associated with deficiency and toxicity.

Manganese is not the same as magnesium. To understand the differences between manganese and magnesium, we'll look at the main properties and benefits of both minerals.

Manganese is an essential mineral that your body needs but cannot make on its own, so you must get it from food or supplements. Your body contains about 10 to 20 milligrams of manganese, located in your bones, liver, pancreas, kidneys and brain, per the National Institutes of Health (NIH).

Manganese benefits your immune system, bone formation and reproductive system, and it's required for the metabolism of protein, cholesterol and carbohydrates. Along with vitamin K, manganese plays a role in blood clotting.

Many foods have manganese, including seafood, whole grains, nuts, legumes, rice and leafy vegetables, per the USDA. Find some of the top manganese-rich foods and their daily value (DV) in the chart below.

Your body absorbs only about 1 to 5 percent of the manganese you get from food, per the NIH. Because manganese is a trace mineral, you need much less of it than magnesium.

The Recommended Dietary Allowance, which is the average daily amount required for good health, for manganese is as follows, per the NIH:

• Children ages 9 to 13 years: 1.6 to 1.9 milligrams
• Teens ages 14 to 18: 1.6 to 2.2 milligrams
• Adults ages 19 and older: 1.8 to 2.3 milligrams
• Pregnant and lactating adults: 2 to 2.6 milligrams

Manganese supplements are available in many different forms including amino acid chelates, gluconate, manganese picolinate, sulfate, citrate and chloride.

Some vitamin-mineral supplements contain manganese. Dietary manganese-only supplements typically contain 5 to 20 milligrams of manganese, per the NIH. Your doctor can help you determine how much manganese you should take daily.

Magnesium is also an essential mineral. Your body needs magnesium to help create energy from the carbohydrates and fats you eat, per the Linus Pauling Institute.

Like manganese, magnesium plays a vital role in the structure and maintenance of your bones. It also helps control muscle and nerve transmission.

Magnesium is required to transport nutrients, such as potassium and calcium, throughout your body. It also helps your body regulate blood sugar levels and maintain healthy blood pressure.

Getting enough magnesium is linked to fewer migraines and depression symptoms, according to a June 2018 study in ​Nutrients​. Plus, the researchers reported a possible positive effect from magnesium for chronic pain and improving post-stroke outcomes.

You can easily get the required amount of magnesium to fulfill your body's needs from many plant and animal foods.

Dark green leafy vegetables, seeds, beans, fish, whole grains and nuts are among the best choices. Generally, high-fiber foods provide magnesium. The mineral is also added to fortified foods, such as breakfast cereals. See the chart below for foods high in magnesium in each food group:

Your body typically absorbs about 30 to 40 percent of the dietary magnesium you need from the food you eat, per the NIH.

The magnesium RDA required for good health is:

• Children ages 9 to 13 years: 240 milligrams
• Teens ages 14 to 18: 360 to 410 milligrams
• Adults ages 19 to 30: 310 to 400 milligrams
• Adults ages 31 and older: 320 to 420 milligrams
• Pregnant and lactating adults: 310 to 400 milligrams

Magnesium supplements are available in various forms, but the kinds that dissolve well in liquid are better absorbed by your body, per the NIH. These may include magnesium in aspartate, citrate, lactate and chloride.

Taking zinc supplements may interfere with the absorption of magnesium.

Magnesium is often found in laxatives such as milk of magnesia. Also, magnesium is sometimes included in remedies for heartburn and stomach upset from acid indigestion.

Manganese deficiencies are very rare in people. According to the NIH, limited evidence suggests that low levels of manganese ​might​ cause symptoms such as:

• Bone demineralization
• Poor growth in children
• Skin rash
• Hair depigmentation
• Decreased serum cholesterol

Low dietary intake of magnesium does not normally cause a deficiency. But if you have certain medical conditions or use certain medications, you may be deficient in magnesium.

Most cases of magnesium deficiency likely result from medical conditions that can upset your body's balance of magnesium, such as diabetes, gastrointestinal diseases or hyperthyroidism, rather than low magnesium intake.

Nausea is a symptom of a magnesium deficiency. Other potential symptoms associated with a magnesium deficiency include:

• Loss of appetite
• Vomiting
• Fatigue and weakness
• Numbness, tingling, muscle contractions and cramps
• Seizures
• Abnormal heart rhythms and coronary spasms

A severe magnesium deficiency could result in low calcium or potassium levels, per the NIH. A magnesium deficiency may cause seizures and may also play a role in decreased cognitive function, per the June 2018 study in ​Nutrients.​

If you have low magnesium intake over a long period of time, this can result in a deficiency, causing symptoms such as fatigue and weakness.

In more serious cases, you could begin to feel tingling sensations or have cricopharyngeal spasms, which are muscle spasms in the neck and throat. You could also experience a change in your heart rhythm, spasms in your heart or seizures.

Manganese is a potent toxicant, not from dietary intake but from exposure through inhaling manganese dust, which is a potential danger to people working in occupations such as mining or welding. Manganese toxicity can also result from drinking water with high levels of the mineral.

Symptoms of manganese toxicity usually affect the central nervous system and can cause:

• Muscle spasms
• Tinnitus or hearing loss
• Unsteadiness and weakness
• Insomnia
• Depression
• Impaired memory and changes in mood

Severe toxicity can progress to neuromotor disorders similar to symptoms of Parkinson's disease, such as imbalance and tremors.

There is no risk of excessive magnesium intake from food, but over-supplementation or medications can result in toxicity, usually causing diarrhea and stomach cramps. Magnesium-containing laxatives and antacids in doses of more than 5,000 milligrams per day have been associated with magnesium toxicity, per the NIH.

Symptoms of magnesium toxicity may include:

• Low blood pressure
• Nausea and vomiting
• Facial flushing
• Urine retention
• Depression
• Muscle weakness
• Breathing difficulties
• Irregular heartbeat or cardiac arrest