The human body has ways to signal nutrient deficiencies before they cause major health issues. Brittle nails may indicate a lack of protein or iron, while eyelid twitching could be a sign of magnesium deficiency. Clicking joints might warn of vitamin D3 or calcium shortage, and premature graying could be linked to vitamin B12 or copper problems. Easy bruising may signal a deficiency in vitamin C or K1. Dr. Saurabh Sethi stresses the importance of early detection to prevent more significant health problems.