Nutritional Pearls: Is Gluten Bad for You?

Daniel is a 32-year-old man who is becoming more concerned about the weight he’s gained in the last decade since he graduated college. He’s looking to develop healthier eating habits. He doesn’t have Celiac disease, but he asks you if you would recommend the gluten-free diet he saw online.

How would you advise your patient?

(Answer and discussion on next page)

Dr. Gourmet is the definitive health and nutrition web resource for both physicians and patients with evidence-based resources including special diets for coumadin users, patients with GERD/acid reflux, celiac disease, type 2 diabetes, low sodium diets (1500 mg/d), and lactose intolerance.

Timothy S. Harlan, MD, is a board-certified internist and professional chef who translates the Mediterranean diet for the American kitchen with familiar, healthy recipes. He is an assistant dean for clinical services, executive director of The Goldring Center for Culinary Medicine, associate professor of medicine at Tulane University in New Orleans, and faculty chair of the Certified Culinary Medicine Specialist program.

Answer: Gluten is not bad for you unless you have documented wheat intolerance or Celiac disease. 

Gluten is a type of protein found in certain grains, including wheat, rye, and barley. Approximately 1% of people have an autoimmune disorder known as Celiac disease, in which consuming gluten causes the body to attack and destroy the villi lining the small intestine. These villi essentially allow the body to absorb nutrients; thus, those with undiagnosed Celiac have symptoms that range from the more overt, such as stomach upset, to the less obvious, such as anemia.

The only treatment for a diagnosis of Celiac disease is a gluten-free diet. In the last several years fad diets have sprung up that assert that wheat gluten is bad for everyone (why varies according to the diet), with the negative effects of a high-gluten diet ranging from increased body weight and fat deposits to “increased gut permeability.”1

The Research

Recently, a team of researchers in Germany took a high-level approach to the issue: the authors noted that some research appeared to show negative metabolic effects when animals consumed gluten and theorized that this would mean an increased risk of death among those humans who consumed gluten when compared to those who did not.2

The authors utilized data gathered through the UK Biobank, a prospective study of more than 500,000 adults at 22 assessment centers across the United Kingdom that began in 2006. At the start of the study the participants responded to a demographic questionnaire along with personal interview and physical measurements. Nearly half of those participants (moer than 211,000 people) also responded to a detailed 24-hour dietary recall questionnaire.

For their analysis the authors excluded those participants who were pregnant, had a history of malabsorption or Celiac disease, whose questionnaires omitted responses to demographic questions such as income, background, or education, those who did not respond to questions regarding smoking, alcohol intake, and those whose physical measurements did not include a measure of body fat. This left a total of nearly 160,000 men and women, with follow-up continuing through August 2020 or until the participant's death.

Those who died during the course of the study had their cause of death categorized first as either due to cancer or noncancer. Deaths from cancer were further categorized into their different types, while noncancer mortality was broken out into cardiovascular disease (with subtypes of ischemic heart disease and stroke) or respiratory disease.

The Results

Using the dietary questionnaires, the participants responded to at the start of the study, the authors were able to analyze the foods the participants consumed to estimate the amount of gluten each person consumed per day. Compared with those without Celiac disease who followed a gluten-free diet, those who consumed gluten, regardless of how much they consumed, did not have an increased risk of death from any cause. They also did not have an increased risk of death from any cancer. The only non-cancerous cause of death that was positively associated with the highest intake of gluten was ischemic heart disease, with an elevated risk of 2%.

What’s the Take Home?

Gluten is not bad for you unless you have documented wheat intolerance or Celiac disease.

Carbohydrates are not bad for you.

Junk food is bad for you. Processed meats such as sausage, bologna, and hot dogs are bad for you. Food that comes in a box should be treated as highly suspect.

It's easier to demonize one ingredient or one macronutrient than it is to follow a healthy, varied diet full of freshly cooked real foods consumed in moderation.

References:

1. Harlan TS. Dr Tim says…leaky gut syndrome quackery. Dr Gourmet. Published online October 2, 2017. Accessed July 12, 2021. https://www.drgourmet.com/column/dr/2017/100217.shtml
2. Behrendt I, Fasshauer M, Eichner G. Gluten intake and all-cause and cause-specific mortality: prospective findings from the UK Biobank. J Nutr. 2021;151(3):591-597. doi:10.1093/jn/nxaa387