Thank you for your question.
Normally, Capsules are made from bovine gelatin.
Thank you for your question
Normally, The best way to get healthy are take a healthy food, Exercise, Sleep well and etc but sometime they can't do well so supplements are the other choice to help them get more healthy.
When they take foods, they can take vitamin and mineral from food. Supplements have the role to fulfill to make sure that they will not deficiency from essential vitamin and minerals.
Best regards
you can take products that contain Kelp which contain iodine inside such as
Biotin H+ , 9 plus calcium , meta pro