Nutritional deficiency diseases occur when the body lacks essential nutrients, leading to various health problems. Common deficiencies include a lack of vitamin C, which can cause scurvy, and insufficient iron, leading to anemia. These diseases can affect anyone, but certain groups, such as the elderly or those with limited diets, are at higher risk. Preventing nutritional deficiency diseases involves consuming a balanced diet rich in fruits, vegetables, whole grains, and proteins. Regular health check-ups can help identify deficiencies early. Education about proper nutrition is crucial for maintaining overall health and preventing these diseases from developing.