Manganese deficiency is very rare because most people get plenty in their diets. However, it does rarely happen in people with certain gene mutations. Read on to find out more about manganese deficiency, the health effects of low manganese levels, and foods high in manganese that boost your levels safely. What is Manganese?
Manganese is a trace mineral essential to all forms of life. It is required for the normal development , growth , and function of our bodies [ 1 , 2 , 3 ].
Manganese serves as an essential part of important enzymes, including mitochondrial superoxide dismutase [ 4 , 2 ].
These enzymes play a role in:
Manganese is found pretty much everywhere: in the air, water, and soil. We readily ingest it through food and water. That’s why manganese deficiency is basically unheard of [ 8 ].
But while it is a required part of a healthy diet, exposure to excess levels can be toxic [ 8 ].
Want to learn more about the benefits and function of manganese in a healthy body? Check out our post here . Normal Levels
Normal ranges of manganese for adults are [ 8 ]: 4-15 μg/L in blood (that is equal to 72.8 – 273 nmol/L)
0.4-0.85 μg/L in serum (the liquid component of blood)
1-8 μg/L in urine
Seniors have slightly lower manganese levels compared to other age groups, likely due to lower gut absorption [ 9 ].
Blood, urine, and saliva levels are poor indicators of manganese exposure or of total manganese present in the whole body [ 10 , 11 , 12 ].
RBC (red blood cell) manganese levels are a better measure of the actual content of manganese in tissues. They can help estimate recent exposure to manganese, spanning a couple of months before the test [ 13 , 14 ].
For those worried about toxicity due to long-term, low-dose manganese, hair, nail, and bone manganese content may give a more accurate exposure estimate [ 15 , 10 ].
However, the uses of both hair and nail manganese tests are limited. People naturally have a large variation between them, and hair and nails are especially prone to contamination from shampoo, nail polish, dust, dirt, and other external factors [ 16 ].
Normal manganese levels in the blood are 4-15 ug/L. Red blood cell manganese helps estimate recent exposure, while bone testing may be more accurate for long-term exposure. Manganese Deficiency
Manganese deficiency is very rare , as sufficient amounts of this nutrient are present in most diets [ 2 , 17 ].
In fact, this condition is so rare that, for a long time, only a few vaguely described cases existed in the medical literature [ 18 , 19 ].
That was until 2015, when a rare genetic mutation in a manganese uptake transporter gene ( SLC39A8 ) was discovered [ 20 , 21 ]. Possible Causes
SLC39A8 serves as a transporter for metals such as manganese, iron , zinc , and cadmium, meaning that it transports these metals into cells. People with mutations in this gene have low blood manganese levels. Zinc levels have been low in some patients, but normal in others [ 22 ].
Infants and children with these mutations experience [ 23 , 22 ]: Severe developmental delay
Short stature (dwarfism)
Low muscle tone (hypotonia)
A movement disorder resembling tremors (dystonia)
Seizures Intellectual disability Inability to align the eyes (strabismus) Deafness Failure to thrive Mutations in this gene are associated with [ 23 , 22 ]: Leigh-like mitochondrial disease , because the enzyme MnSOD (manganese superoxide dismutase) stops working in the absence of manganese, which damages the mitochondria. Type II congenital glycosylation disorder , because manganese is needed for the function of an enzyme that adds sugar residues to proteins and fats (β-galactosyltransferase). In these cases, manganese supplementation normalized enzyme function and helps improve motor function, hearing, and other neurological issues. To avoid toxicity during treatment, doctors regularly monitor blood manganese levels and conduct MRI brain imaging to detect possible manganese buildup [ 24 , 22 ]. Dietary Deficiency When seven men were experimentally placed on a manganese-depleted diet for over a month, they experienced a transient skin rash and decreased blood cholesterol levels. In addition, blood calcium , phosphorus , and alkaline phosphatase ( ALP ) levels rose, possibly due to increased bone breakdown [ 25 ].That said, most of what we know of dietary manganese deficiency comes from animal studies. In animals, low dietary manganese impairs growth, prevents proper bone formation and causes skeletal defects, decreases glucose tolerance, and impairs fat and carb metabolism [ 26 , 27 ].Manganese deficiency due to diet is extremely rare and has never been reported in humans. There are a handful of cases of deficiency due to genetic causes. Symptoms Potential symptoms of low manganese (not due to genetic reasons) include:Because of the rarity of manganese deficiency, these symptoms are more likely to be produced by another underlying condition . If you suffer from symptoms like these, we strongly recommend talking to your doctor, who will order the appropriate tests and make an accurate diagnosis. Conditions Several studies have investigated the effects of low (but not deficient) manganese.Lower manganese levels have been linked to:However, it’s important to note that higher manganese levels are also associated with many of the same conditions. In fact, manganese levels often have a U- or inverse U-shaped relationship with many conditions : the highest and lowest levels are detrimental and the mid-range beneficial.In addition, low manganese is may be an effect of certain diseases and disorders, rather than the cause.Finally, low manganese levels have been observed in some people with: Exocrine pancreatic insufficiency (lack of digestive enzymes made by the pancreas) [ 47 ] But these are isolated cases. In other words, not all people suffering from these diseases have low manganese levels. Therefore, manganese deficiency in these diseases is not considered a health concern , but it may be worth asking your doctor about your manganese levels occasionally if […]