Michael Reed Gach, Ph.D. No Date
Colds are caused by viruses that thrive in your nose and throat when the temperature, acidity, and moisture suit them. When you are run down and your resistance is low, your ability to adapt to environmental changes weakens, making it easier to catch a cold, and the mucous membranes become a perfect breeding ground for viruses. Cold symptoms are the body's attempt to protect itself from these intruders. When a virus enters your nose, for instance, the body secretes more mucus to flush it away.
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