Final answer:
Inflammation is not currently included in the formal definition of metabolic syndrome, despite often appearing with other conditions related to the syndrome.
Step-by-step explanation:
The cause of the metabolic syndrome that is NOT considered a major cause is inflammation. While metabolic syndrome includes traits such as high blood pressure, dyslipidemia, impaired glucose homeostasis, and abdominal obesity, inflammation, although often present, is not currently included in the formal definition of metabolic syndrome. Major contributing factors do, however, include hypertension, oxidative stress, and lifestyle factors, such as physical inactivity, poor nutrition, and high consumption of sweetened beverages. These factors contribute to the development of metabolic syndrome, which is a major risk factor for cardiovascular diseases and type 2 diabetes.