An essential tremor causes part of your body to shake uncontrollably. It can happen in any part of the body but is most common in the hands.
In many people, an essential tremor can get worse over time and keep you from doing simple, everyday tasks. However, the tremors don't cause other health problems.
Essential tremors are more common in people over 40 years old, and may get worse if you are under stress, tired, or experiencing temperature extremes. It's usually most noticeable when you are moving or using the part of your body that has the essential tremor.