human
I've been having trouble focusing at work. What are some of the most common causes of ADD?
assistant
1.  Stress and anxiety can cause difficulty concentrating, as can lack of sleep or too much caffeine.
2.  Poor diet, such as a diet high in processed foods and sugar, can also contribute to difficulty concentrating.
3.  Other possible causes include environmental factors like loud noise or bright lights, certain medications, or hormonal imbalances.