Fasting Insulin

The features of metabolic syndrome have been defined since 1988 by Gerald Reaven. The 5 features include hypertension (HTN), elevated blood sugar (prediabetes or diabetes), abdominal obesity, high triglycerides (TG), and low HDL. Having any combination of 2 or more of these things significantly increases your risk of cardiovascular disease.

Unfortunately, in my experience, these things are often ignored by primary care. There has been a decades-long push to solve for LDL and more recently ApoB. The long-standing belief is that LDL/ApoB causes heart disease. Conveniently for Big Pharma, they make a class of drug that has been worth billions that lowers LDL. These are called “statins” because the end of the generic name always ends with “-statin,” commonly known as Lipitor and Crestor among others. (Interestingly, LDL has never been a defining feature of metabolic syndrome.)

There is growing evidence from folks like David Diamond, Malcolm Kendrick, Aseem Malhotra, Uffe Ravnskov, Zoe Harcombe, and more recently Dave Feldman (among others) who think there is more to the story. Without going down a rabbit hole, these folks argue that inflammation, oxidation, and insulin resistance play a much bigger role and an isolated elevated LDL is not the whole picture.

When people get diagnosed with features of metabolic syndrome, it often happens at their annual check-up. A hemoglobin A1C measures your average blood glucose (sugar) over roughly a 3-month time period. There are set levels that make the diagnosis of prediabetes and diabetes. Blood pressure is checked routinely at annual check-ups. A standard lipid panel tells you TG and HDL among other things. And as far as abdominal obesity, that one is often just a visual diagnosis. Waist to height, waist to hip, waist circumference, and BMI are imperfect but provide some context for your level of obesity. Simply put, if you look in the mirror and your abdomen sticks out farther than your chest, that’s not metabolically healthy.

We know that once you have metabolic syndrome, your body has already sustained metabolic damage. The day you get a diagnosis of one of the features is not the day you started on your path to cardiovascular disease. It just happens to be the day you became aware of it.

The reason this matters is because we know there are things that precede metabolic syndrome by months and even years, maybe decades in some cases. Those things are hepatic steatosis (fatty liver) and insulin resistance.

I see hepatic steatosis in the ER virtually every shift. Abdominal pain is one of the primary reasons patients go to the ER (7-10% of visits) so I get CT scans of abdomens EVERY shift. Usually multiple scans. I also order ultrasounds to look for gallbladder problems regularly. And very frequently, whether we find a specific cause for the abdominal pain or not, I see an incidental finding of hepatic steatosis on the CT or US report.

The vast majority of the time, hepatic steatosis comes from 1 of 2 things: too much alcohol or too many carbs. There are outliers but probably ~95% of cases are from those two things.

My point is that this is not something that should be ignored. Reversing it is possible by cutting out the offending agent: stop drinking or stop the carbs. If your liver has gotten to this point, it will not get better on its own if you don’t change something. And sometimes it won’t get better at all, which is more common with alcoholic liver disease when the liver eventually taps out. Then comes cirrhosis, ascites, jaundice, and a whole host of complications that lead to a miserable death, sometimes in as little as months to a few years. (I’ve seen more than one 30-year-old female with end-stage liver disease from alcohol.)

Fasting insulin is a lab test that can be done at your primary care check-up but in my experience, unless specifically requested or done as part of a comprehensive cardiometabolic panel, it gets ignored. The 2 most common options are an actual fasting insulin level or a HOMA-IR test which is an estimate of insulin resistance.

If you or a loved one are concerned about your metabolic health, ask about a fasting insulin level at your next primary care visit. If you see “hepatic steatosis” listed as an incidental finding on your CT or US, you ignore it at your peril. More bad health things are in your future if you don’t acknowledge it and make some changes.