Manganese deficiency
There is some evidence that human diseases such as amylotrophic lateral sclerosis, acromegaly and epilepsy
are associated with low tissue levels of manganese and that the manganese intake of many people is below
the estimated safe, adequate dietary intake [1]. Reported deficiency symptoms include ataxia, fainting,
hearing loss, weakness in tendons and ligaments and, possibly, type 2 diabetes mellitus (since low levels of
manganese reduce insulin production and impair glucose metabolism).
Manganese deficiency might also develop from failure to absorb the metal, which normally takes place in the
small intestine via a carrier-mediated mechanism. Manganese and iron compete for sites of absorption in
the gut, while fibre, phytates, calcium, phosphorus and excessive intake of magnesium may also interfere
with manganese absorption.
Absorption of ingested manganese is generally low but appears to be relatively higher in infants than in
adults. Bioavailability of manganese from different food types is variable, but is generally low, due to poor
solubility of manganese salts. Once absorbed, Mn in the hepatic portal blood binds to albumin and alpha-2
macroglobulin. A small proportion of Mn in the systemic circulation is bound to transferrin. [8]
Use of manganese supplementation to treat fatigue, nervousness and irritability (possibly by enhancing brain
enzyme activity) and poor memory (by inducing SOD and protecting brain tissue) was originally reported
by Carl Pfeiffer in his book “Mental and Elemental Nutrients” [10]. Pfeiffer suggested that manganese, along
with zinc, will help decrease copper levels by both decreasing absorption and increasing urinary losses. He
claimed that copper, in physiological but higher than normal amounts, can cause psychological problems and
even schizophrenia [11], and that this reflects an underlying tissue manganese deficiency.