The Centers for Disease Control and Prevention is an excellent resource for information and guidance on a variety of health related topics from chronic disease and smoking cessation, to fall prevention and flu shots.
Here are some particular areas of interest for older adults and caregivers:
Falls Among Older Adults
Smoking and Tobacco Use
Chronic Disease Prevention and Health Promotion
Older Adult Drivers
Use the site's A-Z Index to easily find the information you are looking for.