If we are more susceptible to viruses as we age, wouldn’t it be an advantage to get as many viruses as possible in younger years in order to strengthen the immune system in preparation?
Interesting theory, and I can understand the logic of your thinking. But while many viral infections are one-timers — that is, you won’t get sick with the same virus twice — it doesn’t necessarily follow that exposure strengthens your immune system.
Conceivably, just the opposite might occur. If you spend 30 or 40 years hugging sick people, you might risk weakening your immune system. Besides, some of those bugs can be pretty debilitating, and you would spend a great deal of time in bed, feeling miserable. You would also put yourself at risk of serious complications and secondary infections, such as pneumonia.
A spin-off of your theory might suggest that catching all the “one-time” viruses you can early in life would reduce the number available to make you sick when you are older. Unfortunately, there seems to be plenty of viruses to go around, and new ones are always inviting themselves to the party.
With regard to your immune system, I think it is probably better to strengthen it through other means. The healthier you are, the healthier your immune system will be.
Avoid stress — that negative, tooth-grinding type of stress. Develop good sleep habits and make sure you get ample sleep every night. Eat a healthy diet, getting as many nutrients as you can from your food itself, and then taking supplements as deemed necessary by you and your doctor.
Get regular exercise, moderate to vigorous in intensity. Try to live a lifestyle of moderation. That means avoiding excess, when it comes to such things as alcohol, drugs, obesity and anything else that might create long-term health problems.