What Is Gluten Exactly, and Is It Bad for You?

Gluten is a protein found in wheat, barley, and rye, per an article published in May 2016 in NIH News in Health, the newsletter of the National Institutes of Health (NIH). If you don’t have celiac disease, gluten in and of itself is not bad for you — though eating too many simple carbs, like white bread, pasta, and desserts — certainly can be. So how do you know if a gluten-free diet is appropriate for you?

Gluten “should be avoided in patients with celiac disease, gluten sensitivity, or allergy. Otherwise, there is no sufficient evidence to say it’s bad,” Dr. Shatnawei says.

Indeed, “for those who can tolerate it, gluten is not ‘bad’ at all when consumed responsibly. In fact, gluten-containing whole grains, such as bulgur and barley, are rich in fiber and vitamins, and some of the healthiest foods you can eat,” Laifer says.

Yet for people who have celiac disease or gluten sensitivity, consuming gluten can be harmful. For that relatively small group of people, a gluten-free diet prevents the autoimmune response triggered by the ingestion of gluten. This reaction damages the lining of the small intestine, which prevents the body from absorbing key nutrients and can lead to a host of symptoms, including depression, malnutrition, and anemia, according to the NIH newsletter.

Can Going Gluten-Free be Bad for You?

For people who aren’t fighting gluten sensitivity, avoiding gluten is not a health necessity. In fact, going gluten-free can sometimes lead to nutritional deficiencies if not planned right, according to an article published in February 2013 by Harvard Health Publishing. That’s because many Americans get important nutrients like B vitamins through fortified breads and cereals, which contain gluten — while their gluten-free counterparts do not.

In addition, many whole-wheat products contain fiber, which is important for digestion, dietitians agree. If you’re thinking about a gluten-free diet, it’s important to see a doctor first, especially because going gluten-free can skew the results of blood tests for celiac disease, the Harvard Health Publishing article notes.

Ultimately, it’s all about the kinds of foods you’re eating, Laifer says. “Items made with refined flour and sugar, such as cakes and cookies, are a source of ‘empty calories’ and provide little nutrition, regardless of whether they are gluten-free or not,” she says. If you replace these items with unprocessed foods, like fruits and vegetables, you will see a health benefit.

As a general rule, keep in mind that just because something is gluten-free does not mean it is healthy, Laifer says. “Gluten-free products can be higher in calories, fat, and sugar in order to compensate for the texture and mouthfeel that gluten provides, and may lack essential vitamins and minerals,” she says.

Who Absolutely Needs to Go on a Gluten-Free Diet for Health Reasons

People who need to go on a gluten-free diet usually have one of these conditions:

Celiac Disease People who have celiac disease actually have damage to villi (tiny fingerlike tissues that aid in digestion) in their digestive tract because of the chronic inflammation caused by gluten. When they eat even a tiny amount of gluten, they experience symptoms such as bloating, cramping, or specific types of skin rashes.

People with celiac disease might also become lactose intolerant and have iron deficiency anemia, says Rentz. Celiac disease is diagnosed using blood tests and a small bowel biopsy. About 1 in 141 Americans has celiac disease, according to the NIH — and most don’t know it.

Gluten Intolerance or Sensitivity

People with nonceliac gluten sensitivity do not have damage to their intestinal lining. Still, they experience headaches, bloating, fatigue, or diarrhea after eating foods containing gluten. As a result, they believe that a gluten-free diet improves their quality of life.

It’s hard to get a good estimate on the number of people with gluten sensitivity. Some estimates suggest that as much as 10 percent of the population has gluten sensitivity; others estimate that number to be closer to 1 to 3 percent, notes an article published in December 2014 by Harvard Health Publishing.

Gluten sensitivity can be hard to diagnose because it is a diagnosis of elimination: Individuals are tested for celiac disease, and, if the test comes up negative, adopt a gluten-free diet. If their symptoms improve on that diet, only then do they receive the diagnosis of gluten sensitivity. And unlike people with celiac disease, those with gluten sensitivity don’t suffer damage to their small intestine, or the resulting nutritional deficiencies, after consuming gluten.

“If you suspect gluten’s a problem, you should still eat the foods that contain gluten and ask for a blood test,” says Rentz. If you stop eating gluten-containing foods before the blood test, the results will be normal. She stresses that before she helps clients construct gluten-free diets, she wants them to go through all the testing and get a proper diagnosis to know if they have to be “100 percent compliant,” she says.

In addition, if you have a gluten allergy, you should definitely be on a strict gluten-free diet, Shatnawei says.

Irritable Bowel Syndrome (IBS) Some studies show that people with IBS can benefit from a gluten-free diet, Shatnawei says. For instance, a small study published in May 2016 in the journal Clinical Gastroenterology and Hepatology found some evidence that a gluten-free diet could, after just six weeks, provide some benefit to patients with IBS.

What to Do if You Want to Go on a Gluten-Free Diet Without a Medical Reason

Certainly, you can try a gluten-free diet even if you don’t medically need to do so. You can still get a balanced diet on a gluten-free eating plan, Shatnawei says.

Keep in mind that a gluten-free diet can be lower in nutrients like fiber, iron, folate, niacin, vitamin B-12, calcium, riboflavin, and zinc, Laifer says. She recommends choosing enriched whole-grain gluten-free products whenever possible and recommends taking a gluten-free multivitamin if your doctor determines that one may be right for you.

Rentz points out one of the most surprising signs of gluten sensitivity celiac disease is a lack of iron due to poor absorption, and this can also be a problem for people who rely too heavily on prepackaged gluten-free products that might not be nutritionally well-rounded. So giving up gluten when you don’t have to for medical reasons means you may be unintentionally giving up vital nutrients in the process. Read labels and consider a daily multivitamin supplement if you decide to try eating gluten-free.

In addition to consulting your doctor about a multivitamin, be sure you’re getting enough fiber to replace the kind you’d normally get from whole wheat, including from foods like:

• Brown rice
• Quinoa
• Fruits and vegetables
• Beans

In addition, Laifer says, you can also boost your iron intake by eating foods like:

• Fish
• Chicken
• Lean cuts of beef

She also notes that dairy products can provide additional B vitamins and calcium.

Other Things to Keep in Mind Before Going Gluten-Free

One reason you might not want to hop on the gluten-free bandwagon? If you follow a strict gluten-free diet, it actually makes it more difficult to test for celiac disease when you see a doctor, Shatnawei says. That’s because your body won’t be showing the negative reaction to gluten needed to make that diagnosis.

Another drawback, especially if you aren’t a celebrity, is that gluten-free foods can be costly.

So if you haven’t been diagnosed with celiac disease or a nonceliac gluten sensitivity, it’s okay to buck the gluten-free diet trend — you don’t have to cut out gluten because the stars are doing it. Do drop gluten if you are having a reaction to it, but only after seeing your doctor and getting the testing needed for a diagnosis.