Whom do you trust if you don't like to cook? Deli's, family restaurants, microwaving ready meals? All extremely bad choices. Don't cook and you deny yourself (and your mother) healthy food. You cure disease, prevent disease with food, not supplements. Your mother has become that old because her parents, not Mr. McDonald cooked for her.
Fish broth is messy, you have to rinse the bones, sometimes cut out the gills. Maybe you can get your fish shop to do it for a charge. Then dump the bones into a pot, add coarsly chopped vegetables, which I mentioned, add water and gently boil, that's it. The only other thing you have to do is skim off the scum which is the foam rising to the surface. After you have done this add some herbs. Last, throw in chopped parsley and boil for a few minutes, then pour the clear broth into a container. Make lots of it, you only have to do it once. WalMart sells a 22 quart stainless steel pot for under $40.
As for turkey broth, just throw the bones into the pot, then proceed as with fish broth. Extremely easy, you don't have to be a cook, just don't let the broth boil too much and skim. As for mercury in fish bones, select good fish as I mentioned in many past messages. Anyhow, I don't think you should worry about mercury in your mothers state.
I should like to finish with a general statement.
Diseases that often appear later in life remind us that our food choices, indeed, the diet of our Western society is often misguided. If you examine health problems you will often find that bad nutrition and consequently poor digestion can be blamed for failing health. Indeed, I call proper nutrition the foundation of good health and if a building starts to crumble you have to examine and repair the foundation first and foremost. This can generally not be done with supplements or medication. I agree with many experts who believe that many diseases can be traced back to poor nutrition. Good foods and a balanced diet are the most powerful healer. In order to help people suffering from an ailment their diet and digestion should be examined first and foremost.