"The complaints are pretty vague," he said. "When patients come in, they have a hard time explaining exactly what they're feeling, but it's usually being unfocused, having a hard time concentrating at work, being tired."
Doctors say most of the time, it’s due to lifestyle, but in some cases there could be a medical cause.
Collin County shoe store owner A’Lisa Adams says she had been worried when she felt tired or forgetful in the middle of the day.
"Am I beginning to lose my memory?” Adams said. “Or are there other things and conditions out there that make you worry that this isn't right?"
Dr. Moon says lifestyle is to blame for many people, including stress, bad diet and limited exercise.
The bottom line, if you’re concerned about too frequent “brain fog,” check with your doctor.