Metabolic syndrome involves having three or more of the following -- blood pressure equal to or higher than 130/85 millimeters of mercury; fasting blood sugar equal to or higher than 100 milligrams per deciliter; large waist circumference [for men, 40 inches or more, for women 35 inches or more]; low high-density lipoprotein cholesterol [for men, under 40 mg/dL, for women, under 50 mg/dL; and triglycerides equal to or higher than 150 mg/dL.
The study examined more than 700 adults -- 35 percent were vegetarians -- randomly selected from Loma Linda University's long-term study of the lifestyle and health of almost 100,000 Seventh-day Adventists across the United States and Canada.
On average, the vegetarians and semi-vegetarians were 3 years older than non-vegetarians, but despite the older age, the vegetarians had lower triglycerides, glucose levels, blood pressure, waist circumference and body mass index.
In addition, semi-vegetarians had a significantly lower body mass index and waist circumference compared to those who ate meat more regularly.
"I was not sure if there would be a significant difference between vegetarians and non-vegetarians, and I was surprised by just how much the numbers contrast," lead researcher Nico S. Rizzo of Loma Linda University says in a statement.
The findings are publishes in the journal Diabetes Care.