If you’re getting more frequent colds, there could be many reasons why. The first thing you should look at is the amount of air pollution in your home. If there’s not enough air circulating in your home, you could have mold, or other pollutants in the air in your home causing you to get sick. Adding house plants, changing your air conditioner’s filter, installing an air cleaner, using a mechanical ventilator to improve ventilation, and moving your furniture around can help improve the air in your home. Surgi’s Heating & Air Conditioning also has a list of ways to improve air quality here.