Signs of nutritional deficiencies may include symptoms such as fatigue, weakness, and irritability. Specific deficiencies can present unique symptoms; for instance, a Vitamin D deficiency may lead to bone pain and muscle weakness, while a Vitamin B12 deficiency can result in neurological issues and anemia. Other indicators might include changes in skin health, hair loss, or difficulty concentrating. Early identification and intervention are crucial, as nutritional deficiencies can lead to more significant health problems if left unaddressed.