Signs of nutrient deficiencies in active individuals may include fatigue, poor recovery, and decreased performance. For instance, a lack of iron can lead to anemia, resulting in reduced energy levels and endurance. Insufficient intake of calcium and vitamin D may cause weakened bones, increasing injury risks. Also, inadequate protein consumption can impede muscle repair and growth. Symptoms such as hair loss, skin issues, or frequent illness may indicate deficiencies in other vitamins and minerals. Active individuals should maintain a well-rounded diet and, if necessary, consult healthcare professionals for tailored guidance to prevent deficiencies.