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Is a gluten-free diet a healthy diet? The answer may surprise you.
Jan Seacrest, a 45-year-old electrical engineer, and Amanda Malvo, a 38-year-old artist, both had longstanding irritable bowel syndrome that magically clear up when they eliminated gluten from their diets. They were astounded that simply avoiding gluten eradicated issues that their doctors hadn’t been able to remedy, so they purchased and ate as many Certified Gluten-Free products as possible.
Though, digestively, they felt amazingly better, they gradually developed new health issues. At first, Jan found herself craving more sweets. A few months after changing her diet, she noticed that she was having trouble fitting into her pants. Nine months after changing her diet, an annual physical exam revealed that she had gained 25 unwanted pounds, and her blood sugar levels had risen to diabetic levels.
Amanda, on the other hand, didn’t gain weight in her first year of going gluten- free. But she did develop borderline high blood pressure and was diagnosed with fatty liver disease—not the health results she was expecting!
Unfortunately, these stories aren’t unique. While it’s common for people to experience improvements in their health when they first adopt a gluten-free (GF) diet, many gradually develop unwanted weight gain or new health issues, including elevated blood sugar or blood pressure. In one study conducted in 2006, 82 percent of people who went on a gluten-free diet gained weight within the first two years, including 81 percent of the people in the study who were originally overweight. Why? Because while it can help address specific health issues, a gluten-free diet isn’t necessarily healthy.
Most GF Foods Are High Glycemic
Though therapeutic to gluten-sensitive people, most gluten-free foods have a high glycemic index (GI). High GI foods act more like sugar in the body, resulting in higher, more erratic blood sugar levels, which can cause an increase in appetite and cravings for carb-laden foods such as sweets and bread.
When most people start a gluten-free diet, they simply replace the wheat-containing breads, pasta, baked goods, and snack foods they were eating with gluten-free versions of those same foods. But gluten-free bread, pasta, and crackers actually have a higher GI than their gluten-containing counterparts. Even gluten-free whole grains such as brown rice and millet are high-glycemic.
These foods stimulate sharp increases in blood sugar levels, and the body responds by increasing the production of insulin. This combination of high blood sugar and high insulin sets off a cascade of events in the body that promotes weight gain and greatly increases the risk of conditions such as type 2 diabetes and cardiovascular disease.
A standard gluten-free diet is linked to an increased risk of metabolic syndrome in people who have celiac disease or non-celiac gluten sensitivity. Metabolic syndrome, also called insulin resistance syndrome, is a cluster of risk factors—including large waist size, low HDL cholesterol, and elevated blood pressure, blood sugar, and triglycerides—which predispose people to type 2 diabetes and cardiovascular disease.
A 2020 study found that there was an increase in weight gain and a 20 percent increase in the prevalence of metabolic syndrome in patients with celiac disease who followed the gluten-free diet for six months. In patients with gluten sensitivity who ate gluten-free for six months, there was no significant weight gain, but there was a 15 percent increase in the prevalence of metabolic syndrome and a 20 percent increase in fatty liver disease, an excess of fat stored in the liver, which is another condition strongly associated with metabolic syndrome.
The Healthiest Gluten-Free Diet
To experience the health benefits of eating gluten-free without increasing the risk of metabolic syndrome, cardiovascular disease, and type 2 diabetes, research supports shifting to a low-glycemic gluten-free diet. Here are some tips:
- Eliminate most gluten-free bread and cereal, millet, rice, rice crackers, and pasta made from corn or rice, all of which have a high glycemic index.
- Switch to lower-glycemic fruits (apples, pears, peaches, plums, strawberries, oranges) and, for some people, to legumes (kidney beans, split peas, chickpeas, lentils).
- Avoid sugar and sweeteners. Stay away from convenience foods that contain hidden sugar.
- Focus on incorporating healthy fats, protein, minimally processed foods, and dietary fiber to help lower the gluten-free diet’s glycemic impact.
An increasingly popular healthy gluten-free diet is the Paleolithic eating plan that avoids grains, dairy, sugar, legumes, and vegetable oils, and instead emphasizes nonstarchy vegetables, fruits, nuts, seeds, and animal protein. A 2015 diet comparison found that the Paleolithic diet resulted in greater short-term improvements in the symptoms of metabolic syndrome than conventional recommended diets.
Although substituting processed gluten-free breads, pasta, baked goods, and snack foods for wheat-based products may be an easy way to go gluten-free, it sets people up for new, non-gluten-related ailments and diseases, as I explained in my books Going Against the Grain and Gluten Free Throughout the Year. Changing your diet to incorporate low-glycemic gluten-free food choices such as nonstarchy vegetables, beans, nuts, and seeds can, through their beneficial effects on blood sugar and insulin, take you to a new level of health.