No. Obesity can be classified into primary and secondary types according to its cause. Primary obesity, also known as simple obesity, is the most common type and is mainly due to poor dietary habits, such as overeating, particularly excessive intake of fatty foods, and a sedentary lifestyle, and is not secondary to other diseases. Secondary obesity is caused by diseases such as hypothalamic-pituitary disorders, hypercortisolism, hypothyroidism, hypogonadism, and insulinoma. Therefore, the causes of obesity are not infectious factors, so obesity is not contagious. However, lifestyles can influence each other; being around people with poor lifestyles for a prolonged period can also lead to adopting poor lifestyle habits and potentially result in obesity.