Human beings need four things to survive:
- Air
- Water
- Food
- Bacteria
1. Air:
We need oxygen from the air to survive. Oxygen help our body to acquire energy.
2. Water:
We need to drink water to survive. Our body is approximately 60 percent water, brain is 70 percent water, and our lungs are nearly 90 percent water. Each day, our body must replace 2 to 2.5 liters of water through ingested liquid and foods.
3. Food:
Without proper nutrition, our body cannot function. When we eat a balanced diet, our body obtains the fuel and nutrients it needs to accomplish various bodily tasks. For example, our body needs minerals to make hormones, build bones and regulate our heartbeat.
4. Bacteria:
They live in us, on us and multiply in our body very fast. They perform various vital functions to keep us healthy –beginning from digestion, vitamins synthesis, absorption of minerals and micronutrients, control of diarrhea and constipation. They enhance the immune health that makes us fight viral, bacterial and fungal infections. They also reduce the intensity of allergic diseases like eczema, running-nose, asthma, food allergies and reduce cancer risk, as well.
http://discoverykids.com/articles/why-we-cant-live-without-bacteria/
