Sulfated polysaccharides, particularly those derived from seaweeds (such as fucoidan from brown algae and carrageenan from red algae), have been studied for their effects on the gastrointestinal (GI) system, including the stomach. Scientific research, primarily in vitro and animal studies, has suggested that these compounds possess gastroprotective properties. For example, sulfated polysaccharides can enhance the production of gastric mucus, inhibit the adhesion of pathogenic bacteria (such as Helicobacter pylori) to the stomach lining, and reduce oxidative stress and inflammation in gastric tissues. Some studies also indicate that these polysaccharides may help protect against gastric ulcers induced by stress or nonsteroidal anti-inflammatory drugs (NSAIDs).

The mechanisms thought to underlie these effects include their ability to interact with cellular receptors, modulate immune responses, and maintain the integrity of the mucosal barrier. However, while the preclinical evidence is promising, robust human clinical trials are limited. Most of the current support for their use in promoting stomach health is based on laboratory and animal data rather than large-scale human studies.

In summary, there is moderate scientific evidence (rating: 3) supporting the use of sulfated polysaccharides for stomach health, but more high-quality clinical research is needed to confirm their efficacy and safety in humans.