Algin is a fiber molecule found in most seaweeds.

When ingested, algin can attract various metals, possibly including lead and mercury, and remove them from our system. Alginates have been used for heartburn and acid reflux for decades.

Sodium alginate, the sodium salt of alginic acid, is an ingredient in some antacid products and is used for the treatment of gastroesophageal reflux disease or GERD. When sodium alginate reacts with gastric acid, a viscous gel called an alginate raft is formed. The alginate raft floats on top of the gastric contents and acts as a barrier to acid and food reflux.

References

Mandel KG, Daggy BP, Brodie DA, Jacoby HI. Review article: alginate-raft formulations in the treatment of heartburn and acid reflux. Aliment Pharmacol Ther. 2000; 14:669-690.Carr TE, Harrison GE, Humphreys ER, Sutton A. Reduction in the absorption and retention of dietary strontium in man by alginate. Int J Radiat Biol Relat Stud Phys Chem Med. 1968; 14:225-233.