No, not all diseases are caused by infections. Some diseases are caused by poor lifestyle, bad eating habits, pollution or lack of nutrients. These are called non-communicable diseases, like diabetes or anaemia.
class 8 science chapter 3 health the ultimate treasure question answer
Class 8 Science Curiosity Textbook Chapter 3 Health – The Ultimate Treasure question answer
Diseases are not always caused by infections. Many illnesses are non-communicable and result from unhealthy habits, poor diet, lack of exercise, pollution or genetic factors. For example, diabetes, asthma, cancer and deficiency diseases like scurvy or goitre are not caused by germs but by lifestyle or nutritional issues. So, disease prevention includes not just avoiding infections but also living a healthy, balanced life.
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