A person who forgets things easily can be described using the word "forgetful," while the state of being forgetful is called "forgetfulness." The words "absent-minded," "inattentive" and "unmindful" are synonymous or have meanings close to "forgetful."
Although it is normal for most people to forget things every once in a while, frequent memory loss, along with other symptoms, may be a sign of bigger mental health issues such as dementia, Alzheimer's or mild cognitive impairment. A declining memory is also a common sign of aging.
Medications, head trauma or injury, depression, alcoholism, vitamin B-12 deficiency, hypothyroidism, and tumors are also among the reasons some people become more forgetful or lose memories.