Kwashiorkor primarily affects children due to several factors, including the timing of weaning, which often leads to a rapid decrease in protein intake. This condition typically arises in children around the age of 10, characterized by a severe lack of protein despite adequate energy intake. In contrast, adults generally have a greater muscle mass and energy reserves, making them more resilient to protein deficiencies and starvation-related diseases. The discussion also touches on the relationship between kwashiorkor and conditions like celiac disease, highlighting how both can lead to symptoms such as abdominal distension due to protein absorption issues. The conversation raises questions about the increasing prevalence of kwashiorkor in middle-aged individuals, suggesting that underlying health issues may contribute to this trend. Overall, the complexities of protein-energy malnutrition and its varying impacts on different age groups are emphasized.