If someone were to switch to a low-protein diet without consulting their doctor, the negative reactions their body would have include impaired immune function, muscle loss, reduced bone density, swelling, anemia, fatty liver disease, intestinal problems, hair loss, nutrient deficiencies and psychological changes.
Explanation:
Protein is an essential component for proper muscle growth, tissue structure, enzymatic reactions, endocrine function, immune and circulatory system. A low-protein diet is mostly beneficial for individuals with specific health conditions like liver disease, impaired kidney function and genetic disorders that affect protein metabolism, such as homocystinuria and phenylketonuria.
A low-protein diet without proper medical supervision may result in certain health risks. The low dietary protein causes a decrease in muscle mass and other nutrient deficiencies, which results in physical weakness. Protein is used to produce white blood cells, antibodies, blood proteins and immune molecules, like interferons, interleukins, cytokines, etc. A low dietary protein adversely affects the body's ability to produce enough immune molecules and may lead to more frequent and severe infections. The low-protein diet can weaken the bones by impairing the digestive tract’s ability to absorb calcium. The bone density decreases over time and as a result, the accelerated loss of skeletal mass occurs. Therefore, a low-protein diet without proper medical supervision may cause fatigue, lethargy,  impaired immune function, muscle loss, reduced bone density, swelling, anemia, fatty liver disease, intestinal problems, hair loss and psychological changes.
