Conditions associated with manganese deficiency include:
Impaired growth
Fertility issues
Impaired glucose tolerance
Altered lipid metabolism
Weakness
Osteopaenia and osteoporosis
Premenstrual symptoms
Reduced coagulation
Hair reddening
Dermatitis
References:
Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Vitamins A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium and Zinc. Washington, DC: National Academy Press, 2001. Available from: https://www.ncbi.nlm.nih.gov/books/NBK222310/
World Health Organization. Trace elements in human nutrition and health. 1996. Available from: http://www.who.int/nutrition/publications/micronutrients/9241561734/en/
Wada O. What are Trace Elements. JMAJ. 2004; 47(8):351-358.