Manganese: The Mighty Trace Mineral

Health Benefits of Trace Minerals

Manganese may be a trace mineral, but don’t let that unassuming title fool you.

This mighty mineral gets it name from the Latin word “magnes” which means magnet. But manganese is far more important for its health implications than its magnetic force (it isn’t even magnetic!)

See, manganese plays a crucial role in your bone health, prevents a number of health conditions, and keeps you alive! (More on that in just a moment.)

So, it’s time to take note of manganese! But how much manganese do you need and which foods are the best sources? Don’t worry, we’ll cover these questions along with the benefits of manganese, safety concerns and more below. So let’s get to it!

Top 3 Benefits of Manganese

Manganese may not live in the same limelight as more prominent minerals like calcium, but the potential benefits it provides are incredible!

Given its rather low-key status, there still isn’t a wealth of quality research on manganese. But the research so far suggests manganese is extremely important. See, manganese is a co-factor (meaning it basically gives the go-ahead) for the production of some vital chemicals and enzymes in your body.
Here are the three major reasons you can’t live without manganese… literally!

Kickstarts Bone Health

Manganese is one of the 13 essential minerals you need to support healthy bones. In fact, manganese is necessary for the very first steps of building bone.

You need manganese to produce a chemical called chondroitin sulfate. And chondroitin sulfate, along with an enzyme called osteocalcin, forms the material in which the fibers and cells of connective tissue are embedded. This material helps to maintain healthy bones and joints! And speaking of healthy joints, chondroitin has been linked with relieving pain in people with osteoarthritis too.

What’s more, manganese is also the co-factor for your bone-building osteoblast cells to produce a number of enzymes. The osteoblasts then use these enzymes as tools in their bone-building work!


Let’s take a look at a study to demonstrate manganese’s role in healthy bones.

A 2.5-year placebo-controlled study enrolled 225 postmenopausal women from the San Diego greater metropolitan area. All of the women were over 50 and in good general health.

The women were given either:

    • A placebo supplement
    • A calcium supplement providing a total of 1,000 mg of calcium per day (250 mg per tablet taken 4 times daily)
    • A trace mineral supplement containing copper (5 mg), manganese (2.5 mg) and zinc (15 mg), taken once daily
    • Or both the calcium and trace mineral supplements.

The results? The women who took the placebo supplement, the calcium supplement alone, or the trace mineral supplement alone all saw a drop in spine bone mineral density (BMD.) But the women who took both the calcium and trace mineral supplements saw an increase in their spinal BMDs!

    • Placebo (39 women) -2.23%
    • Calcium alone (29 women) -0.50%.
    • Trace minerals alone (35 women) -1.66%
    • Calcium + trace minerals (24 women) +1.28%

Granted, the sample sizes are a little on the small side, but this study demonstrates that building bone requires a multi-nutrient approach. And that includes manganese.

Crucial For Hormone Production

Besides being a co-factor for chemicals and enzymes directly involved in building bone, manganese could also be the co-factor for some very important hormones which have an indirect impact on your bone health.

Research suggests manganese is involved in the production of thyroxine– the main hormone secreted by your thyroid. (If you were wondering, the thyroid is a butterfly-shaped gland that sits just below your Adam’s apple).

What’s more, low levels of manganese are a common occurrence in people with hypothyroidism. To date, there isn’t a substantial enough body of research to be conclusive. But given that hypothyroidism is a condition where your thyroid doesn’t produce enough thyroid hormones, it’s plausible that manganese would play an important role.

So what does that mean for you? Well, your thyroid hormones play a vital role in many bodily functions. These functions include regulating: your metabolism, heart and digestive function, muscle control, brain development, mood and most relevantly for osteoporosis, bone maintenance.

But that’s not all. Manganese is a very busy mineral! It also plays a part in the production of cholesterol. You may know cholesterol as something you need to keep an eye on, but the truth is cholesterol, in moderation, is crucial. All your hormones, including the sex hormones estrogen, progesterone, and testosterone are made from cholesterol. And just like the thyroid hormones, sex hormones play a role in your bone health.

You can read more about how thyroid and sex hormones impact your bone health on our “Top Causes of Osteoporosis” page.

Literally Keeps You Alive!

It sounds a little overdramatic, but manganese really is extremely important.

As we’ve already covered, manganese is a co-factor for a lot of crucial enzymes and hormones. But the most important of all is manganese-dependent superoxide dismutase (MnSOD.) You’ve likely never heard of it, but you’ll soon see it’s a big deal!

As you know, humans need oxygen to survive. Now, about 90% of the oxygen you inhale is used to generate adenosine triphosphate (ATP) inside mitochondria– the powerhouse of cells. Think of ATP as the currency your body spends to fund all sorts of metabolic activities. So far so good…

But here’s where things get a little hairy: during the process of generating ATP, around 2 to 5% of the oxygen escapes! What’s worse, the runaway oxygen is in a highly reactive, free radical form called superoxide anion. This is bad news because superoxide anion is comparable to a zombie. What we mean by that is that superoxide anion is so unstable and reactive that it will literally attack any molecules it comes into contact with. And it’ll turn them into free radicals too! Then these free radicals will attack other molecules and so on and so on…

Now, your body is very sophisticated and is prepared to neutralize the runaway oxygen by using an array of specialized enzymes. And you guessed it… MnSOD is one such enzyme! In fact, MnSOD is arguably the most important, because it lives inside your mitochondria (the epicenter of the free radical breakout.) This makes MnSOD your first line of defense against the free radicals that could attack and destroy every cell in your body given the chance!

To put things in perspective, mice bred to lack functioning MnSOD die shortly after birth. And mice bred with a partially functioning MnSOD have a very short and unpleasant lifespan.

*Please note: At AlgaeCal, we strive to deliver you the most accurate, reliable research, and that wouldn’t usually include animal studies. But in the case of MnSOD, it wouldn’t be ethical to conduct such research on human participants.

The Bone Health Benefits of Selenium

Selenium appears to be one of the least understood trace minerals in terms of how it impacts bone and joint health, but studies show that it does appear to have a positive impact.


In a recent study, scientists clipped the toenails of 940 volunteers and measured the amount of selenium in each sample. They also tested the volunteers for incidence of osteoarthritis. They found that the group of volunteers who had osteoarthritis, also had lower levels of selenium in their bodies than the people who didn’t have osteoarthritis. While the scientists are not sure how low levels of selenium contribute to osteoarthritis, they found that for every additional 0.1 parts per million of selenium in the toenails, there was a 15 to 20 percent lower risk of osteoarthritis in the knees!16 In another study, scientists used a blood thinning drug on rabbits to induce conditions of low bone density. Once the rabbits exhibited the signs of bone loss, they were given a combination of vitamins E and C. While these vitamins helped partially prevent further bone loss in the rabbits, once selenium was added to the mix, the rabbits’ bone structure virtually returned to normal!17

How Much Manganese Do You Need?

So without manganese, you wouldn’t get very far at all. But how much do you need?

Well, as we mentioned a little earlier, there still isn’t a wealth of quality research on manganese. In fact, there was insufficient data on manganese requirements to set a Recommended Dietary Allowance, so the Food and Nutrition Board of the Institute of Medicine set an adequate intake instead. The adequate intake of manganese in the United States is currently set at:

    • 2.3 mg per day for men aged 19 and above
    • 1.8 mg per day for women aged 19 and above
    • 2 mg per day for pregnant women
    • 2.6 mg per day for breastfeeding women

But the problem with “adequate intakes” is in the name. They only provide an adequate amount! These recommendations were set with preventing a manganese deficiency in mind, not promoting optimal health. If you recall the study we mentioned in the “Kickstarts Bone Health” section a little earlier, the women who improved their BMDs took a calcium supplement and a trace mineral supplement. That trace mineral supplement contained 2.5 mg of manganese.

Other human studies show that a dietary intake of 3 mg per day may not even be enough to prevent a decline in the body’s levels of manganese! In short, most Americans probably aren’t getting enough manganese for optimal health. Rather than the current recommendations, recent research suggests a recommended dietary intake of 3 to 5 mg per day.

Manganese Safety Concerns

Manganese is generally considered to be safe, and adverse reactions are uncommon. The tolerable upper limit for manganese is set at 11 mg a day, at which no adverse effects have been reported.

There is one safety issue to cover, however. Exposure to extremely high levels of airborne manganese can be toxic. But the key thing to note here is that manganese toxicity is generally only seen in individuals who work in iron or steel factories, manganese ore mines, chemical plants, or the fuel oil industry. People who work in these environments are regularly exposed to extremely high concentrations of airborne manganese (approximately 20,000 times higher than a regular environment.)

Workers exposed to high levels of manganese experience health problems that tend to involve the nervous system and include behavioral changes and slow, clumsy movements. At its most severe, this combination of symptoms is called manganism, which resembles Parkinson’s disease.

The Top Food Sources of Manganese

Since it’s a trace mineral, you won’t find a truly generous helping of manganese in many foods. But nonetheless, here are some of the top “manganese-rich” foods to add to your bone-healthy shopping list.

Note: There are a few factors that come into play when evaluating the manganese content of food. See what they are below the table.

Best Food Sources of Manganese
Food Serving Size Amount in mg


1 teaspoon


*Oats, cooked

1/2 cup


*Brown rice, cooked

1 cup


*Garbanzo beans, cooked

1 cup



1 cup



1 cup


Pumpkin seeds

1/4 cup



4 oz



4 oz



0.75 cup



1/4 cup


Sweet potato

1 cup


*Lentils, cooked

1 cup


*Lima beans, cooked

1 cup


Collard greens

1 cup


*Navy beans, cooked

1 cup



2 teaspoons


Sesame seeds

1/4 cup



1 cup


Black pepper

2 teaspoons


Swiss chard

1 cup



1 cup



1 cup



2 teaspoons


*Tea (green)

8 oz

0.41 – 1.58

*Tea (black)

8 oz

0.18 – 0.77

* Your body won’t be able to absorb the full amount of manganese stated in these foods. That’s because these foods contain high amounts of tannins or fiber that bind to the manganese, preventing your body from absorbing it fully.

Before you stock up on oats and pineapple, there are a few things to bear in mind when shopping for manganese-rich foods:

Is the food product organic?

If you’re a regular reader of the AlgaeCal blog, you’ll know that we recommend opting for organic produce whenever possible. And the same goes for manganese sources too. See, “conventional” agricultural techniques use pesticides and chemicals that deplete the nutrient levels of produce (and actually promote bone loss in some cases!)

Of particular concern for the manganese level of produce is a herbicide called glyphosate (Round Up). A crop absorbs the minerals it contains from the soil, right? But glyphosate oxidizes the manganese in soil, which means the crop can no longer absorb it. Which obviously means that the crop contains next to no manganese for the consumer!

Whole grains vs refined grains

The Total Diet Study– which documented the daily mineral intake of eight age-sex matched groups for seven years– revealed that the biggest dietary contributor of manganese is grains.

But not all grains are created equal. Refined grains like white flour provide far less nutrition than their whole grain counterparts. And that goes for manganese too. See, the milling process that creates a refined grain removes a huge portion of the mineral content. In fact, a whopping 90% of the original manganese content is lost when wheat is milled into refined flour for example!

Manganese Takeaways

It may be a trace mineral, but as you’ve seen, manganese is mighty!

Manganese plays a role in your bone health and your very survival. But despite these distinguished accolades, research suggests many Americans aren’t getting enough. It doesn’t help that the adequate intake was set with preventing a deficiency in mind rather than optimal health too.

More recent recommendations fall between the 3 to 5 mg per day range. A modest amount on paper, but it can be trickier to meet that mark than you’d think. Especially given the relatively small amount of manganese in food in general and the short-change you get from conventionally grown foods.

Unless you eat a near completely organic diet, you could be consuming less manganese than you think.

Still, foods are the best source of manganese, but if you’re reading this post, you may be wondering how much is in a daily dose of AlgaeCal Plus? Well, AlgaeCal Plus provides only .11 mg of manganese. Of course, .11 mg is only a small complement to your dietary manganese consumption, but AlgaeCal Plus provides manganese along with all of the other 13 essential bone-building minerals as part of a multi-nutrient approach to bone health.

If you recall the study we mentioned a little earlier, the postmenopausal women who took calcium along with several trace minerals like manganese (a multi-nutrient approach) were the only group that improved their bone densities. And AlgaeCal Plus is clinically supported to increase bone density too!

The bottom line? AlgaeCal Plus provides everything you need to build new bone and increase your bone density. But you’ll still need some extra manganese to reach the recommended 3 to 5 mg a day, so use the table above to ensure you’re getting the right food sources for optimal health.