You can add seaweed aka sea vegetables to your diet. e.g., https://draxe.com/nutrition/kelp/ https://draxe.com/nutrition/kelp/ If you live on the coast, ther

You can add seaweed aka sea vegetables to your diet. e.g., https://draxe.com/nutrition/kelp/ https://draxe.com/nutrition/kelp/ If you live on the coast, there are almost certainly culinary varieties of sea weed in your area. You may need a fishing license-- in California, we can take up to 10 lbs (~4.5 kg) without a license. Avoid areas anywhere near the outfall of a stream, storm drain, etc.