Mackerel is used to support or help treat Metabolic Syndrome primarily based on scientific evidence. Mackerel is a fatty fish rich in omega-3 polyunsaturated fatty acids (PUFAs), particularly EPA and DHA, which have been widely studied for their effects on metabolic health. Several clinical trials and meta-analyses have shown that regular consumption of fatty fish like mackerel can improve key risk factors associated with Metabolic Syndrome, including elevated triglycerides, blood pressure, and markers of inflammation. Omega-3s are known to help reduce triglyceride levels, increase HDL cholesterol (the "good" cholesterol), and may contribute to improved insulin sensitivity and endothelial function.

While studies consistently support omega-3s' role in lowering triglycerides and reducing cardiovascular risk, the effects on other Metabolic Syndrome components, such as fasting glucose or waist circumference, are less pronounced. Nevertheless, dietary guidelines from reputable organizations (e.g., American Heart Association) recommend regular fish consumption as part of a heart-healthy diet, which overlaps with recommendations for managing Metabolic Syndrome.

In summary, there is moderate scientific evidence supporting the use of mackerel as part of dietary strategies to manage Metabolic Syndrome, mainly due to its omega-3 content and beneficial effects on lipid profiles and inflammation.