Should I have a password in my application

I'm wondering if I need a password in my app. I'm targetting home users where multiple people can use the same application, but each has their own profile. The data is not sensitive, but could be embarrassing (health, weight, etc). Is this enough to warrant a password or is the profile enough?

Edit To clarify some more about my application. I will store the users' weight, height and eating habits/values (开发者_StackOverflow社区calories, nutrients, etc.) The user is free to name the profile whatever they want and is not asked for any true personally identifiable information. The data will be stored on their local computer. The reason I wanted to add the password was in case Wifey did not want Hubby to see her weight or vice versa.

You absolutely should put a password in. Nobody will spite you for added security within reason. By-user data, whether you consider it sensitive or not, should be password protected.

You most definitely should implement protection for people's data. Also look at local laws that protect data. In the United States all health information are protected by HIPAA regulations which will require SSL connection to the site - there are many other rules.

Some people might not want others to see their information, so you should also consider settings to allow them to keep their data private.