Malnutrition is primarily caused by:

Malnutrition is primarily caused by poor nourishment, which is often the result of unhealthy eating habits. This encompasses a lack of essential nutrients, vitamins, and minerals due to inadequate food choices, improper food preparation, or insufficient food intake. Inadequate nourishment can lead to both undernutrition and overnutrition, where the body does not receive the right balance of nutrients necessary for optimal health. Factors such as socioeconomic status, knowledge about nutrition, and access to healthy foods significantly influence eating habits, highlighting the importance of making informed dietary choices to prevent malnutrition.

The other causes listed, while they may impact health, do not directly define malnutrition in the same way. Excessive exercise, for instance, primarily affects energy balance and may lead to issues like muscle depletion if not properly managed with adequate nutrition. Overconsumption of sugary foods can lead to other health problems, such as obesity and diabetes, rather than malnutrition per se. Genetic predispositions can influence how a person's body metabolizes food and nutrient needs but do not fundamentally define the condition of malnutrition itself, which is rooted in dietary habits and nutrition quality.