a native hydrous magnesium silicate, sometimes with a small amount of aluminum silicate; used as a dusting powder. The inhalation of talc is associated with a wide variety of respiratory disorders.
Factors contributing to poor sleep include vitamin and mineral deficiencies. Magnesium deficiency can cause insomnia; lack of potassium can lead to difficulty staying asleep; and vitamin D deficiency has been linked to excessive daytime sleepiness.
The only proven benefit of vitamin D is its role in helping calcium build strong bones. But that's far from the whole story. Vitamin D helps regulate the immune system and the neuromuscular system. Vitamin D also plays major roles in the life cycle of human cells. Vitamin D is so important that your body makes it by itself -- but only after skin exposure to sufficient sunlight. This is a problem for people in northern climates.