Is "how I learned to swallow capsules (pills) a good UC application personal statement topic?

I would suggest that you don't use the learning to swallow pills. (Side note: I can't swallow pills either) Choose something else. Maybe the conference you held because that shows leadership ability. A personal statement usually includes the following. You need a good attention grabber. In general you want your essay to follow this order: Paragraph 1-2 attention grabber. Think of an experience in your life that really showcases who you are. Be detailed. Discuss something significant in your life. It could be anything. Or discuss why you want to be in your profession or what story inspired you to study what you are studying. Paragraph 3-4. Highlight your academics: GPA, classes. What skills you learned in class that will help in succeeding in college. Awards and honors that you have received. Sports or clubs that you are in. Paragraph 5. Jobs that you have had that relate to your major? Any other things about yourself that you want to include Paragraph 6: Conclusion. In this conclusion you may want to re-state your main qualifications. You can also include any of the following statements: My goal is.... I deserve this scholarship because....

Seriously, I think you should go with how I learned to swallow pills. It's different (which is always good...you want your essay to stick out), and but conveys the same "persistence" message they all love to hear.