Millions of Americans have sworn off gluten, claiming a gluten-free diet has helped them shed pounds, boost their energy and feel healthier all around. Gluten by itself is neither harmful nor unhealthy — it’s simply a protein found in several grains. Yet throngs of folks swear by gluten-free diets, typically avoiding bread, crackers and pasta. And that’s just the start. This compound is an integral ingredient in myriad foods, such as salad dressings, soy sauce, mustard, baked beans and beer. Its widespread presence can make cutting gluten out of your diet surprisingly difficult, inconvenient, time-consuming and expensive.

Which begs the big question: Is this wildly popular trend truly beneficial to health — or at least enough so to make ousting gluten worth the trouble? More importantly, is swearing off gluten even safe?

What Is Gluten, Anyway?

In simple terms, gluten is a protein substance found in wheat, rye, barley, brewer’s yeast, malts (malt vinegar, malt flavoring) and a wheat-rye hybrid called triticale. It works like a glue, giving bread and pastas their spongy, chewy texture. Gluten is what helps doughs stretch and thickens sauces and soups. When these common foods are prepared without gluten, it’s fairly easy to tell the difference in texture and even taste.

Am I Gluten Intolerant?

People can have a wide spectrum of reactions to the protein, ranging from mild sensitivity to full-blown celiac disease. Less severe cases can cause symptoms like gas, bloating and diarrhea. But these symptoms can overlap with or be mistaken for conditions like lactose intolerance, irritable bowel syndrome and even gynecological issues.

Gluten intolerance can also show up in more surprising ways that don't seem linked to bowel issues. Specifically, some people experience nausea, general fatigue or skin irritation; iron and vitamin D deficiencies can also be a sign, especially in younger people.

But the big issue with gluten intolerance seems to be brain fog, where you struggle to stay focused. Brain fog can be extremely frustrating and even physically exhausting if it persists.

To determine whether you have a gluten sensitivity, try an elimination diet. You need to completely avoid gluten for at least a month, not just a week or two. Assess how you feel after the elimination period; if your symptoms have improved or cleared, then you might have found your answer. But to confirm, slowly introduce gluten back into your menu to see if your problems return.

How Does Celiac Disease Differ?

Although they may yield many similar symptoms, non-celiac gluten sensitivity and celiac disease are very different. Celiac disease is actually an inherited autoimmune condition. If you’re merely sensitive to gluten yet you consume it, you probably won’t feel well, but you’re not seriously harming your body long-term. However, when celiac sufferers consume gluten-containing foods, it creates a toxic reaction in their immune system that inflames and damages their stomach lining and small intestine. This prevents food from being absorbed properly, which can cause unintended weight loss and malnutrition — and potentially trigger many other problems. For example, the inability to absorb iron can lead to anemia; not absorbing adequate calcium and vitamin D can lead to bone-mass deterioration and eventually osteoporosis.

An estimated 2 million Americans have celiac disease, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Many of these cases are undiagnosed, meaning a lot of people don't know they have the condition. Celiac disease is more common among women and white people. And there's a strong hereditary component. When family members of someone with celiac disease are screened, 50% of them also get diagnosed as having it.

How Do I Know if It's Celiac?

If you’re experiencing suspect symptoms, pinpoint the problem as quickly as possible. An elimination diet may be all you need to detect non-celiac gluten sensitivity, but it’s smart to rule out celiac disease just in case. The condition can be diagnosed by a simple blood test, which is inexpensive and very accurate. But this part is crucial: For the test to read accurately, you must have it done while consuming a gluten-containing diet.

Doctors can also run genetic testing to detect the genes related to celiac, HLA DQ2 and DQ8 genes. Ninety percent of people with celiac disease will have one or other of these genes. This test can be performed while you’re on a gluten-free diet.

There’s no cure for celiac disease. The only treatment is religiously following a gluten-free diet. Without the constant influx of gluten, the small intestine begins to heal and overall health tends to improve.

Gluten-Free Myths

Even without a celiac disease diagnosis or established sensitivity, many Americans still opt to go gluten-free. Many do so in hopes of curing migraine headaches, fibromyalgia, chronic fatigue and other maladies — even though research doesn't show gluten causes these problems.

Many people also shun gluten in hopes of fast-tracking weight loss. When gluten first became a buzzword a few years back, it was a common misconception that gluten had something to do with weight gain. Not true. Although some who ditch gluten do drop pounds, their weight loss is rarely a direct result. In most cases, what really happens is the elimination of gluten greatly reduces the variety of foods they can eat, especially packaged foods. With fewer choices, many turn to fresh fruit and vegetables, lean proteins and low-fat dairy products. Diets rich in these foods usually reduce total caloric intake, and guess what? People naturally lose weight.

But oftentimes those who go gluten-free don't lose weight. In fact, many end up gaining weight. Blame savvy food marketers who, capitalizing on the popularity of gluten-free dieting, line grocery store shelves with gluten-free cookies, cakes and snacks. Without gluten to bind the ingredients in these foods together, manufacturers must use more fat and sugar to make their already-unhealthy products taste good, boosting calories counts above their gluten-containing counterparts.

Just compare a single serving of regular pretzels to a gluten-free variety. The regular brand will have around 110 calories and 1 gram of fat, while the gluten-free pretzels pack in 140 calories and 6 grams of fat. When gluten-averse consumers chow down on these high-fat, high-sugar items, before long they are loosening — not tightening — their belts.