The word "dizzy" is used to describe everything from feeling faint or lightheaded to feeling weak or unsteady. Dizziness that creates the sense that you or your surroundings are spinning or moving is called vertigo.

Keeping your sense of balance depends on your brain processing a variety of information from your eyes, your nervous system and your inner ears. However, if your brain can't process signals from all of these locations, if the messages are contradictory, or if your sensory systems aren't functioning properly, you may experience dizziness and loss of balance.

Dizziness is one of the most common reasons older adults visit their doctors. Aging increases the risk of developing any of several conditions that may cause dizziness. Although it may be disabling and incapacitating, dizziness rarely signals a serious, life-threatening condition. Treatment of dizziness depends on the cause and your symptoms.

Causes
Under normal circumstances, your sense of balance is controlled by a number of signals that your brain receives from several locations:
Eyes. No matter what your position, visual signals help you determine where your body is in space and how it's moving.

Sensory nerves. These are in your skin, muscles and joints. Sensory nerves send messages to your brain about body movements and positions.

Inner ear. The organ of balance in your inner ear is the vestibular labyrinth. It includes loop-shaped structures (semicircular canals) that contain fluid and fine, hair-like sensors that monitor the rotation of your head. Near the semicircular canals are the utricle and saccule, which contain tiny particles called otoconia (o-toe-KOE-nee-uh). These particles are attached to sensors that help detect gravity and back-and-forth motion.

Good balance depends on at least two of these three sensory systems working well. For instance, closing your eyes while washing your hair in the shower doesn't mean you'll lose your balance. Signals from your inner ear and sensory nerves help keep you upright.

However, if your central nervous system can't process signals from all of these locations, if the messages are contradictory, or if the sensory systems aren't functioning properly, you may experience loss of balance.