Metabolic Syndrome: The 5 Criteria and What 3 of Them Means
Five measurements, and three of them makes a diagnosis. What the criteria are, why they cluster, and which one moves first.
Metabolic syndrome isn't a disease so much as a pattern — a cluster of five measurements that tend to travel together and that, in combination, predict risk better than any one of them alone.
The five criteria
You meet the definition with any three:
- Waist circumference above the threshold for your sex and ancestry
- Triglycerides at or above 150 mg/dL, or treatment for it
- HDL cholesterol below 40 in men or 50 in women, or treatment
- Blood pressure at or above 130/85, or treatment
- Fasting glucose at or above 100 mg/dL, or treatment
Note how many can be met "or treatment for it" — being medicated for a criterion still counts toward the diagnosis.
Why they cluster
Because insulin resistance sits underneath most of them.
High insulin promotes triglyceride production in the liver and lowers HDL. It affects sodium handling in the kidney and blood vessel tone, which raises blood pressure. It's directly reflected in fasting glucose. And visceral fat — the waist criterion — both drives insulin resistance and results from it.
So five numbers, one substantial common cause. That's why an approach aimed at insulin sensitivity tends to move several at once rather than one at a time.
Which one moves first
Useful to know, because it manages expectation.
Triglycerides respond fastest and most dramatically, often within weeks. They're strongly driven by refined carbohydrate and alcohol, and they're the most food-responsive number on the whole list.
Waist follows, and tracks the visceral fat that matters.
Fasting glucose is slower, because it reflects hepatic glucose output and takes longer to shift than post-meal readings do.
Blood pressure varies enormously between individuals.
HDL is the slowest and responds more to exercise — particularly resistance training — than to food.
If you're checking progress at eight weeks, look at triglycerides and waist.
What the approach looks like
Nothing bespoke. Protein at every meal, carbohydrate slower and placed at midday, alcohol reduced, walking after meals, resistance training twice a week, sleep protected.
The reason that unremarkable list works here is that it targets the common cause rather than the individual criteria.
The bit worth holding onto
Meeting three of five is a risk statement, not a verdict. The criteria are thresholds on continuous measurements — being just over one is very different from being far over three, and the same intervention moves you back across the line as moved you over it.
Try this week: find out which of the five you actually meet. Most people know one or two of their numbers and assume the rest.
Education, not medical advice. Metabolic syndrome should be assessed and managed by your doctor.