כשרות תוסף מזון שנלקח כמניעה

If a substance is taken as a medicine, one needn’t be concerned with kashrut. With current medical research showing the anticancer properties of antioxidants, does one have to be concerned with the kashrut of the gelatin capsules used?

Thank you for your answer. I would like to clarify an important point: I am, thank G-d, not a cancer patient. I have a family history of cancer (my father), and I am an ex-smoker, so I have a higher-than-average chance. I am interested in taking anti- oxidants as a preventive measure.