MN is almost always ranked in top 5 (often #1) when it comes to health (Google away...). But I don't doubt that if you look hard enough you can find something, somewhere that has MN ranked lower. In the end, I can fill a page with links showing MN ranks at or near the top of all US states according to various health indices. Again, almost always above CA.
But let's give you the benefit of the doubt and break health down further to just obesity. After all that is what this is about. The obesity rates for CA and MN are within 2% (pretty close) and although both are "good" related to most other states, the numbers are both too high. For MN, the rates for heart disease and diabetes are better so the 2% obesity difference is "gobbled" up by these facts when it comes to health.
http://stateofobesity.org/adult-obesity/
If you are basing your personal fat "study" and making judgements on eyeball comparisons between your neighborhood in San Diego with your friends and family in outstate MN, I'm guessing your opinion would be just as skewed as a person living in uptown Mpls flying to Oakland and observing people there.