Why do I not get many colds?

On average, an adult will experience 2 or 3 colds or flu each year. There are a few factors which might be contributing to your fortunate situation:
 
1. Your immune system could fundamentally be stronger than average - this means that it is more likely to identify viruses and deal with them effectively before they trouble you.

2. Being able to avoid crowds of people, especially during the times when cold and flu viruses are lurking around, means that you are less likely to be exposed to viruses.

3. You may have been exposed to many cold viruses over a number of years, even if you may not have felt ill clinically. This will have given you a level of immunity to many viruses over time. This natural phenomenon explains why younger people tend to pick up more infections.

4. You may be eating a particularly healthy diet which is providing plenty of the nutrients that the immune system needs.

5. If you're taking an immune-supporting remedy such as Echinacea then this may be supporting the immune system to fight off infections before you notice any symptoms.
 
Conversely, there are some people who tend to pick up more infections than others. This is mainly because their immune systems are less effective and because of this, are less likely to mount an immune response to an infective viruses, even if a previous infection by the same viruses has taken place.