Don't Ignore Numbness in Your Hands and Feet Gradual onset of numbness or tingling in the hands and feet often occurs among working-aged adults from repetitive and forceful activities, e.g. prolonged use of a computer keyboard and mouse. This symptom can have a wide variety of causes including poor nutrition (particularly vitamin B deficiency). But if the numbness and tingling feels worse and associated with pain, it may be a sign of peripheral neuropathy that should not be left untreated.