My favorite links for quality information on health issues:
Presidents Challenge (PCPFS)
Mayo Clinic
WebMD
National Institutes of Health
American Diabetes Association
American Heart Association
Real Age
MedicineNet.com
Right Health
Family Doctor
Exercise planning and motivation
America's Running Routes
Exercise Prescription
Human Kinetics
Reliable Nutrition Information
The Worlds Healthiest Foods
What's For Dinner
Eat Well Guide
Calorie King