Micronutrient deficiency occurs when the body lacks essential vitamins and minerals required for optimal function. Common symptoms are fatigue, weakened immunity, poor hair, skin and nails, trouble losing weight, and persistent hunger despite adequate calorie intake. Deficiencies can adversely affect energy production, metabolism, brain function, and resilience to illness. Treatment starts with dietary assessment and the addition of nutrient-rich foods or targeted supplementation. Functional medicine may employ detailed testing to identify specific deficiencies, followed by personalized nutritional support. Results typically include improved energy, mental clarity, and overall health, as well as reduced cravings and better weight management.