Celiac Disease and Metabolic Syndrome

You may never have heard of "metabolic syndrome," but here's why you should care about this odd-sounding medical condition: having it means you're at higher risk for serious problems like heart disease and diabetes.

Researchers have looked into whether there's a connection between metabolic syndrome and celiac disease with mixed results, although one study indicates that going gluten-free raises your risk of metabolic syndrome. So yes, if that study is borne out by future research, this could be pretty important.

On the other hand, another study found a lower incidence of metabolic syndrome among people with celiac disease than in similar people who didn't have celiac. So it's definitely not clear yet how having celiac affects your risk for metabolic syndrome, and whether the gluten-free diet plays any role.

What in the World Is Metabolic Syndrome?

Metabolic syndrome isn't actually a disease—instead, it's the name given by healthcare providers to a group of risk factors that, when found together, increase your chances of suffering from heart disease, stroke, or diabetes.

There are actually five of these risk factors involved, although you only need to have three of them to be diagnosed with metabolic syndrome. According to the National Institutes of Health, someone with metabolic syndrome is twice as likely to develop heart disease and five times as likely to develop diabetes as someone who does not.

The metabolic syndrome risk factors include:

• A large waistline. People with metabolic syndrome often have fat around where their belt would fall, and fat in this area is riskier than fat on, say, your hips.
• A high triglyceride level. Triglycerides, a type of fat that circulates in the bloodstream, are measured as part of cholesterol testing.
• A low level of so-called "good" HDL cholesterol (again, measured as part of cholesterol testing).
• High blood pressure.
• High fasting blood sugar.

If you're on medications to treat any of these issues, they still count toward your risk for metabolic syndrome.

So How Does This Tie Into Celiac Disease?

As I said above, the research has been mixed into whether people with celiac disease have a higher or lower risk of metabolic syndrome, on average. However, a recent study, unfortunately, doesn't contain great news.

The study, published in 2015 in the medical journal Alimentary Pharmacy & Therapeutics, looked at how many people with celiac disease also had metabolic syndrome at the time of their celiac diagnosis, and checked back in to see how many had metabolic syndrome one year after starting the gluten-free diet.

The researchers ultimately followed 98 people with newly diagnosed celiac disease. Two of these fulfilled the diagnostic criteria for metabolic syndrome at the time they were diagnosed, but after 12 months eating gluten-free, 29 people were deemed to have metabolic syndrome.

In addition, the number of celiacs whose waistline was in the high-risk range for metabolic syndrome jumped from 48 people at diagnosis to 72 a year after going gluten-free. The number of people with high blood pressure quadrupled, from four to 18, and the number with high fasting blood sugar more than tripled, from seven to 25. Those with high triglycerides doubled, from seven at diagnosis to 16 a year later.

Fortunately, the celiac diagnosis and subsequent gluten-free diet didn't seem to affect levels of HDL cholesterol much—32 people had low HDL at diagnosis, and 34 had it a year later. But the other risk factor measurements definitely moved in the wrong direction.

Does This Mean the Gluten-Free Diet Is Unhealthy?

No, not necessarily—and of course, if you have celiac disease you must be gluten-free, as it's the only way to prevent further damage to your intestinal villi. Overall, about one-third of all U.S. adults have metabolic syndrome, so this study (which was conducted in Italy, where metabolic syndrome rates are in the high 20 percent range) shows celiacs moving from lower risk at diagnosis to average risk a year later.

Still, even though metabolic syndrome is commonplace these days, you still don't want to have it, and the study showed more celiacs did have it after a year of eating gluten-free.

The researchers in this study say they don't know whether it's the gluten-free diet itself that contributes to the development of excess weight in people diagnosed with celiac, or whether it's some other factor. But it does point up a fairly acute need to be aware of what you eat and its potential to affect your entire health status, not just your small intestine.

Several studies have shown that a "conventional" gluten-free diet (one filled with gluten-free-labeled substitutes for wheat-containing foods such as bread, cookies, cereals and snack foods) may not be nutritionally balanced because the gluten-free foods aren't fortified with vitamins and minerals as often as their gluten-filled counterparts.​

Study Shows Reduced Risk for Celiacs

The research on this subject has been mixed. In fact, a study from Beth Israel Deaconess Medical Center in Boston published in the medical journal Gastroenterology in 2013 found that celiacs had a much lower rate of metabolic syndrome and type 2 diabetes when compared to similar people without celiac disease.

That study, which included 840 people with celiac disease, found only 3.1 percent of them had type 2 diabetes, compared with nearly 10 percent of similar people without celiac. It also found only 3.5 percent of the celiacs had metabolic syndrome, compared with nearly 13 percent of controls.

Part of the lower risk seemed to be due to the lower weights of those with celiac disease, the authors found. But even after accounting for the weight difference, people with celiac disease still had a lower incidence of metabolic syndrome than similar people without the digestive condition.

So with one study saying celiacs' risk of metabolic syndrome rose in the year following diagnosis, and another indicating celiacs seem to have a lower rate of metabolic syndrome than similar people without celiac, what does all this mean?

That's not clear, and it's something for future research to explore. But if your healthcare provider tells you that you have metabolic syndrome or that you're at risk for developing it, you may want to consider consulting with a nutritionist. In fact, the 2015 study's authors recommend seeing a nutritionist, both when you're first diagnosed with celiac disease and again several months later, to make sure you're getting all the nutrients you need while not raising your metabolic syndrome risk.