Just to be clear...Modifilan is an entirely different product than Nature's Sunshine Algin.

Modifilan is a brown seaweed extract, containing only about 50% algin. The other 50% is made up of other ingredients that occur naturally in brown seaweed. Two of these ingredients are Fucoidan and Laminarin, which are sulfated polysaccharides—complex sugar molecules that contain sulfur.

Many people with mercury toxicity have trouble with sulfur-containing foods and herbs. Since mercury has an affinity for sulfur, it binds with sulfur molecules. So, substances like fucoidan and laminarin may actually help chelate mercury. This is fine, as long as you can handle mercury chelation.

I don't think you're getting enough algin (by taking Modifilan) to adequately absorb the mercury/sulfur molecule complexes, which means you could reabsorb and redistribute the mercury. Maybe this helps explain your stomachache?

I definitely would not take this product if I still had my amalgams in. If you're post-removal and trying to chelate, you might need to take extra Algin to help offset the detox effects. I would also take lots of Vitamin C - Citrus Bioflavonoids and Vitamin E Complete w/Selenium also. Based on some studies I've read recently, selenium is extremely beneficial for mercury toxicity.