1. drinking water
Water is essential to good health, yet needs vary by individual. These guidelines can help ensure you drink enough fluids, and water is essential to proper functioning of your body. Humans need to drink water to survive. Your body is approximately 60 percent water, your brain is 70 percent water, and your lungs are nearly 90 percent water.
Your body uses water in many ways. Water cushions and lubricates joints; nourishes and protects the brain, spinal cord and other tissues; keeps the body's temperature normal; and helps remove waste through perspiration, bowel movements and urination. Humans are composed mostly of water, which is not surprising when you consider that humans descended from single-cell organisms that originated in the oceans millions of years ago. When your water intake does not equal your output, you can become dehydrated. Fluid losses are accentuated in warmer climates, during strenuous exercise, in high altitudes, and in older adults, whose sense of thirst may not be as sharp.