Any stomach surgery can affect your absorption of vitamins and you need B-12 for functions of your body, add heart problems or, as with, me open heart surgery and the need is greater. My heart doctor recommended B-12 shots once a month which i did for a few years, but decided to try these in an effort to boost the value of B-12. What a difference! after my yearly labs, my GP said I could cut my shots back to every other month and eventually no shots at all! I do not like taking pills so when I saw there was a gummy I was on board! thy are super yummy and do the job! I'm changing all my vitimins to gummies if they come that way. Its like having a sweet desert twice a day! Yes, I do recommend!