Here is a good list of the benefits of Shilajit and what it is used for from 

• Contains Fulvic and Humic Acids
• Contains at least 85 Minerals in Ionic Form
• May assist in Obesity, Hypertension, Arthritis
• Decreases Pain and Helps Injuries
• Anti-inflammatory
• Cognitive Stimulation
• Assists Memory Ability and Support for Alzheimer’s
• Purifies Blood
• Liver and Kidney Detoxification
• Supports Immune System
• Helps to Increase Strength and Endurance
• Supports Sexual Function and Potency
• Regulates Blood Sugar
• Supports Metabolism and Mitochondria
• Mitigates effects of Fatigue by Increasing ATP
• Improves Ability to Handle High Altitude Stresses
• Increased Sperm Count and Motility
• Normalizes Hormonal Activity
• Ovogenic (Helpful in ovulation for females)
• Helps Lower Cholesterol and Triglycerides
• Antioxidant
• Cardio protective
• High in Bio available Calcium
• Corrects Protein Synthesis