Eating fewer proteins can have several negative impacts on your body, and there are some signs that you may experience if you are not consuming enough protein. Some of the most common signs of protein deficiency include thinning hair, brittle nails, and dry skin. You may also experience muscle weakness, fatigue, and a decreased immune system. Additionally, you may feel hungry more often or experience cravings for sugary or carb-heavy foods. If you are concerned that you are not getting enough protein in your diet, it is important to speak with a healthcare professional or registered dietitian to develop a plan for meeting your nutritional needs.