E86.0 is the ICD-10 code for dehydration
Keratin is what makes up hair, horns, claws, hooves and more. It additionally protects epithelial cells from damage or stress. However, keratin is extremely insoluble in water and organic solvents. You are unlikely to find it in said solvents.
Tapeworms and lice are examples of parasites that can cause diseases in humans.
Because physical activity can help bump up the production of your brains neurotransmitters called endorphins.