Norwegian Kelp (Ascophyllum nodosum) is sometimes used as a supplement to support metabolic health due to its content of iodine, polyphenols, fucoidan, and other bioactive compounds. There is some emerging scientific evidence suggesting potential benefits of kelp and other brown seaweeds on components of Metabolic Syndrome, such as glucose metabolism and lipid profiles. Several small clinical trials and animal studies have indicated that extracts from brown seaweeds can inhibit carbohydrate-digesting enzymes (like alpha-amylase and alpha-glucosidase), potentially reducing postprandial blood glucose spikes. Additionally, kelp may have modest lipid-lowering effects and anti-inflammatory properties.

However, human clinical evidence is still limited. Most studies are of short duration, use small sample sizes, or examine related species or isolated compounds rather than whole Norwegian Kelp as consumed in supplements. A few pilot studies have shown improvements in fasting glucose or cholesterol in overweight adults, but results are inconsistent and not yet robust enough for firm conclusions. The majority of evidence comes from laboratory or animal models. There is no strong tradition of using Norwegian Kelp specifically for Metabolic Syndrome in historical medical systems.

In summary, while there is some scientific evidence supporting potential benefits of Norwegian Kelp for aspects of Metabolic Syndrome, the overall evidence base is weak to moderate (rated 2/5), and more high-quality human studies are needed before it can be firmly recommended for this purpose.