People on a WFPB diet need to insure an adequate intake of vitamin B-12. Vitamin B-12 is made by bugs in the environment. If we consume neither non sanitary water and veggies nor animals that consume non sanitary water and veggies, then supplementation is the way to go.

I use iodized salt. Getting the recommended amount of salt as iodized table salt (not salty prepared foods) will take care of iodine need on a WFPB diet. Health-food stores should have dulce (a form of seaweed) or drops for iodine.

Other than for B-12 and iodine, be wary of supplementation. For example, people that get beta-carotene in their food are healthier than people that don't. But when beta-carotene supplementation is compared to a placebo, the people on the placebo are healthier. The reason probably is that beta-carotene is not alone. There is alpha-carotene all the way to omega-carotene and beyond — about 50 usable carotenoids in all. So the body's attempt to use a combination of these is defeated if all the pertinent receptors are filled with beta-carotene.

The story of the failed attempt to improve health by supplementing with vitamin E is the same as the story with beta-carotene.