Non-communicable diseases can be of the following types:
1. Deficiency diseases: Caused by the lack of nutrients. E.g., Night blindness, beri beri etc.
2. Metabolic diseases: Due to some abnormality in the metabolism of the body. E.g., Diabetes, uremia etc.
3. Genetic diseases: Due to some error in the genetic code. E.g., Haemophilia, colour blindness etc.