Best Answer: There are many factors that can weaken your immune system, depression certainly wont strengthen it. But here are some other factors that may cause your immune system to be bad, or increase your risk to illnesses.
ARIZONA'S PUBLIC LANDS -- BOTH BLESSING AND BURDEN. Arizona covers 72.6 million acres and is the 6th largest state (after Alaska, Texas, California, Montana and New Mexico); but only 15 states have fewer people. Land for growth ought to be plentiful, yet in Arizona there is a short supply in many communities where it is needed most.
A US acre is 1 sq/mi = 640 acres 663,267 x 640 = 424,490,880 acres http://en.wikipedia.org/wiki/Square_mile. According to Wikipedia, the area of Alaska is 663,267 square miles. Since there are 640 acres per square mile, then Alaska covers 424,490,880 acres. * 228 million acres that are part of the federal domain.