Can Eliminating Gluten Be Unhealthy?
Gluten is a special type of protein found in wheat, rye, and barley. It helps give baked goods elasticity, providing them with that chewy texture so familiar in good bread. In addition, gluten provides strength and structure to baked goods, and as a result, it is found in varying quantities in almost all of them, breads in particular. But you can also find it in most types of cereals, crackers, and pasta.
Ever since Elizabeth Hasselbeck’s best-selling book The G-Free Diet: A Gluten Survival Guide (Center Street, 2009) hit bookstores, there has been an uptick of articles about gluten and going “gluten-free.” Such articles as: “Does gluten deserve its bum rap?” (Washington Post, October 27, 2009) and “Nutrition-conscious are drawn to gluten-free diet” (Orlando Sentinel, September 29, 2009) discuss the health benefits and costs of a gluten-free diet. Many statements have been made in the media about the gluten-free diet, and this Health Fact Check will examine three.
1.Â In the video, “Gluten-Free Craze” by Consumer Reports,Â it is stated that gluten-free products have nutritional deficiencies.
Do gluten-free products have nutritional deficiencies?
Vegetables, fruits, beans, nuts, seeds, wild fish, lean meats, brown rice, and quinoa all are naturally gluten-free and are nutritionally superior to gluten-containing processed foods such as bread, cakes, pastries, cereals, and pretzels. Most of the gluten consumed in this country is enriched wheat flour, meaning that the B vitamins (B1, B2, Niacin, and Folic Acid), iron, and often fiber have been added back in after the milling process removes them. The gluten-free flours amaranth, buckwheat, millet, and Teff, contain B vitamin levels comparable to whole wheat flour.
|B Vitamin Content in Flours|
Gluten is not an essential nutrient. Therefore, replacing the gluten in your diet with whole foods such as vegetables, fruits, beans, nuts, seeds, wild fish, and whole, gluten-free grains will result in a more nutritious diet. Processed baked goods of any kind, with gluten or gluten-free, are less nutritious than whole foods and should not be the foundation for any healthy diet.
2.Â In the Harvard Medical School Health Letter publication from June, 2009, it states that gluten-free diets can end up lacking essential nutrients, including fiber.
Do gluten-free products lack fiber?
Many vegetables, fruits, beans, nuts and gluten-free grains have more fiber per serving size than wheat bread:
Â½ cup cooked lentils= 16 grams fiber
1 cup berries= 8 grams of fiber
1 cup broccoli=5 grams of fiber
1 cup cooked oats= 4 grams 0f fiber
Â¼ cup almonds= 4 grams of fiber
1 slice wheat bread= 3 grams of fiber
1 slice white bread= 1 gram of fiber
If you examine fiber content based on a cup of flour, whole wheat is still not first in its class; in fact, it isn’t even in the top three:
Many gluten-free whole foods and flours contain more fiber per serving or per cup than foods containing gluten and wheat or white flour.
3.Â In the British Journal of Nutrition, October, 2009 publication, a recent small study with 10 people consuming a gluten-free diet concluded that populations of beneficial gut bacteria, such as Bifidobacterium and Lactobacillus, decreased, while counts for Enterobacteriaceae and Escherichia coli increased. The press release from the study was picked up by many news sources, including healthnews.com, foodconsumer.com, celiac.com, and PubMed, from the National Institute of Health.
Does a gluten-free diet lead to poor gut health?
The only published research that supports this claim is from the small study of ten people conducted in Spain that examined the effects of a gluten-free diet on the composition and immune function of gut microflora. (De Palma, G., Nadal, I., Collado, M., Sanz Y. (2009). “Effects of a gluten-free diet on gut microbiota and immune function in healthy adult human subjects.” British Journal of Nutrition
Spanish researchers analyzed the gut microflora of ten healthy subjects with an average age of 30 assigned to consume a gluten-free diet (GFD) for one month. Analysis of the participants’ feces showed that populations of healthy gut bacteria decreased following the gluten-free diet, while populations of unhealthy bacteria increased. No significant differences in dietary intake were found before and after the GFD except for significant reductions in polysaccharides. Detailed food diary entries were not part of the published study, so it is unclear why the subjects ate fewer polysaccharides (found in fruits and vegetables) on the gluten-free diet.
Polysaccharides are complex carbohydrates containing starch, cellulose, and pectin, a soluble dietary fiber present in all fruits and vegetables. It has the potential to lower serum cholesterol, improve insulin resistance, and regulate and protect the gastrointestinal tract. Dietary sources of polysaccharides include beans, citrus fruits, apples, bananas, beets, cabbage, and carrots.
The gastrointestinal health benefits of soluble dietary fiber is well-established and accepted within the medical and health community, including the Food and Drug Administration, the Mayo Clinic, and numerous published studies in food science and nutrition journals. Fiber increases the bulk of the feces, speeds the transit of bowel contents, and is said to protect the body from the effects of cancer-producing substances contained in some foods. A recent study has shown that a fragment released from pectin, found in all fruits and vegetables, binds to and is believed to inhibit galectin 3 (Gal3), a protein that plays a role in all stages of cancer progression.(Gunning et al. “Recognition of galectan components of pectin by galectin-3.” The FASEB Journal, October 2008; DOI: 10.1096/fj.08-106617)
Answer: Firmly Inconclusive.
It is not surprising that the beneficial gut bacteria decreased in the Spanish study when the dietary intake of polysaccharides was significantly reduced. The study does not prove that a gluten-free diet leads to poor gut health, only that a significant reduction in polysaccharides, plus a change to a gluten-free diet, changes the composition of gut bacteria. More research is necessary to determine if gluten or dietary polysaccharides affect gut health.