Insomnia is often due to a state of deficiency. There can be qi deficiency, where the person wakes frequently without agitation or restlessness, and is able to fall back asleep easily. This corresponds with issues around electrolyte regulation by the kidneys and adrenals. The next is yin deficiency, with frequent waking along with restlessness, corresponding with sex hormone imbalance and more frank adrenal fatigue. Yang deficiency, where the person must sleep in an upright position, presents biomedically as heart failure. Blood deficiency is where the person wakes after 3-5 hours of sleep but is able to fall back asleep after 30-60 minutes. This corresponds to problems with liver glycogen storage.