Manganese is one of those elements commonly referred to as “trace” minerals within the human body, because they’re found and required only in relatively tiny quantities. But that description should not be taken as reducing the importance of manganese in any way. Indeed the very name is derived from the Ancient Greek word for magic; evidencing the special powers which they attributed to it. Modern science is probably too cautious to go as far as that, but there’s no doubt that manganese has a number of vital functions within the body.
Manganese is an essential element in the production of a number of vital enzymes. Perhaps particularly important amongst these is superoxide dismutase, an anti-oxidant enzyme which has a crucial role in protecting the mitochondria of every cell in the body from the oxidative free radical damage which can lead to DNA damage, premature ageing and even, eventually, degenerative disease. Manganese dependent enzymes are also essential for the effective metabolism of protein and carbohydrates from the diet, as well as cholesterol.
In addition to helping maintain normal cholesterol levels, it has also been noted that cardiac patients tend to have depleted levels of manganese in the heart muscle, and there is research evidence to suggest that manganese may also help protect against arterial damage.
Manganese is also regarded as important for bone and joint health. Some commercial preparations containing glucosamine, a popular supplement marketed as an aid to joint flexibility and for reducing the pain of osteo-arthritis, also contain significant quantities of a manganese compound, and there’s evidence that manganese, like glucosamine, has a significant effect in helping the repair of joint cartilage. Low blood levels and deficiencies of manganese have also been associated with an increased incidence of osteoporosis, ie brittle bones; and wound healing depends on prolidase, another manganese activated enzyme.
Although orthodox medicine remains reluctant to accept the link, there is evidence that low levels of manganese are associated with the glucose intolerance characteristic of diabetes, and, coincidentally or not, it has also been noted that many so-called “natural” nutritional therapies for the disease are often based on manganese rich herbs. No one is claiming that manganese supplements may act as an alternative treatment for diabetes, but many practitioners maintain that when taken together with a manganese rich diet, they may well assist sufferers to manage their blood sugar levels. Finally, a number of research reports have confirmed an associative, but not necessarily causal, relationship between low manganese levels and brain (epileptic) seizures in both humans and other animals. Whilst it is generally recognised that more research is required, it seems reasonable to suggest that ensuring good levels of manganese in the body may have some protective effect. The US Food and Nutrition Board has recommended an upper safe limit for manganese intake of 11 mg a day for adults, and there are potential concerns about manganese toxicity. These appear to arise, however, from the direct inhalation of manganese dust and the consumption of manganese contaminated water or heavily polluted air, rather than from diet or supplements.
These external pollutants apart, there is much more likely to be a deficiency of manganese than an excess. Whole grains, leafy green vegetables, certain fruits and green or black tea are reasonably good sources, but many modern Western diets may still struggle to provide even the minute amounts required. As usual, the stripping of nutrients from the soil along with our increased dietary reliance on heavily refined grains are the main culprits. But in the case of manganese this problem is compounded by its negative interaction with other essential minerals needed by the body in larger quantities. It appears, for example, that the absorption of manganese from food decreases in proportion with the amount of iron contained in that food, and the amount of iron stored in the body.
Blood levels of both manganese and the important anti-oxidant, superoxide dismutase have been found to be reduced in individuals following a program of iron supplementation, and similar results have been found in people supplementing with magnesium, as is very commonly recommended in the interests of cardiac and cardiovascular health.
Relatively high doses of calcium supplements have also been found to reduce the absorption of manganese and perhaps also increase its rate of excretion from the body. But none of the above effects should be taken as reasons not to supplement with these other minerals should such a program be regarded as potentially beneficial. They are, however, yet more evidence of the holistic operation of the body’s systems and the mutual interdependence of all the many nutrients on which these rely.
Thankfully, though, the answer to the problem is simple enough. It is to ensure that no supplements of minerals, or for that matter vitamins, are ever taken in isolation, but only in the form of comprehensive multi-vitamin and multi-mineral supplements. And of course, these should always be regarded as being in addition to a nutritionally well balanced diet rather than a replacement for it. Such a multi-mineral supplement should provide more than sufficient manganese but it is also worth noting that good intakes of both vitamin C and zinc, in particular, appear significantly to improve manganese absorption.
