A Short Guide to a Long Life/David B. Agus, M.D./190 pgs.

Dr. Agus divides his book into three sections: What to Do, What to Avoid, and Doctor's Orders. In a concise and highly readable fashion, Dr. Agus advises the reader in steps to improve and take charge of his/her health (and health issues). It's an informative read!

Top Screwups Doctors Make / Joe & Teresa Graedon / 262 pgs

This is another good book by the Graedon's who are pharmacists of the "peoples pharmacy" fame. It is full of practical advise for going to the doctor and/or the hospital. They include a very helpful list of drugs that may cause memory loss so if you are worrying about Alzheimer's, you might check your regular medications for "anticholinergic" properties from the list on page 164.
They then discuss many common diagnoses such as cholesterol, celiac, thyroid, depression, asthma, diabetes, osteoporosis and others. they point out things to watch for and possible alternate causes or things to try. It's just a practical book. They used to have the drug interaction book that was very helpful as well.