The Gluten-Free Diet and Health: Facts vs. Fiction?
The gluten-free diet is considered the gold standard and the only effective treatment for coeliac disease. When followed correctly, it reduces inflammation and promotes gut healing, minimising the risk of associated comorbidities such as bone density loss, vitamin and mineral deficiencies, the development of other autoimmune diseases, subfertility in both men and women, neurological complications, and the risk of small bowel cancer.[i],[ii]
It does, however, still fall victim to stigma, which may contribute to low adherence to treatment.
“Decades of research and clinical practice have demonstrated that a gluten-free diet is currently the only effective treatment for coeliac disease. After diagnosis and initiation of a gluten-free diet, most patients experience a significant improvement in their quality of life - remarks Nick Trott, Specialist Coeliac Dietitian at the Royal Hallamshire Hospital, Sheffield - When patients transition to a gluten-free diet, they must acquire substantial new knowledge and implement strategies to prevent the ingestion of gluten both inside and outside the home, while adhering to established dietary guidelines to support their overall health. At an individual level, this can be challenging and complex, exacerbated by inconsistent levels of care available to patients and prevalent misconceptions about the gluten-free diet itself.”
As with any medical therapy, the benefits of the gluten-free diet must be balanced against the potential risks. Historically, it has been suggested that the gluten-free diet may adversely affect patients’ metabolic health, increasing the risk of obesity, diabetes, and heart disease[iii],[iv]. Additionally, there has been concern that gluten-free products may be higher in energy and saturated fat while being lower in essential nutrients and dietary fibre. However, recent research is helping to clarify these risks and identify strategies to support patients in minimising them, whilst ensuring they still benefit from the therapeutic effects[v].
The 20th International Coeliac Disease Symposium – ICDS (5th-7th September 2024, Sheffield UK), a leading scientific meeting that brings together the world’s foremost experts in coeliac disease and gluten-related disorders, provides an opportunity to review the latest research and treatment strategies in the field. In particular, the panel ‘Evolution of the Gluten-Free Diet: Enhancing Nutritional Quality and Achievability for Improved Quality of Life’ explored the link between the gluten-free diet and health.
THE GLUTEN-FREE DIET AND THE RISK OF OBESITY: after diagnosis and the adoption of a gluten-free diet, the gut heals, and the digestion and absorption of food and nutrients improve. Historically, it has been observed that a subset of patients may experience unhealthy changes in body composition, along with weight gain[vi]. However, recent reviews indicate that a gluten-free diet does not significantly increase the risk of becoming overweight or obese[vii]. Mr Trott emphasises, “Health professionals should not assume that patients with coeliac disease will automatically gain weight, but they should monitor their dietary habits. Anyone who requires a medically necessitated gluten-free diet should be offered support and personalised nutrition advice to ensure they can maintain this dietary approach within the context of established healthy eating guidelines”.[viii],[ix]
THE RISK OF DIABETES AND HEART DISEASE ON A GLUTEN-FREE DIET: In recent decades, there has been growing interest in the potential link between coeliac disease and cardiometabolic disorders, including type 2 diabetes and cardiovascular disease. Research findings on the association between coeliac disease and these conditions have been mixed.[x],[xi] However, a recent large-scale study found that patients with coeliac disease on a long-term gluten-free diet did not have an increased risk of developing type 2 diabetes[xii]. Further research is still needed in this area, however recent studies underline the importance of providing appropriate medical and nutritional support, as well as regular follow-ups, for patients with coeliac disease.
ARE ALL GLUTEN-FREE SUBSTITUTE PRODUCTS ‘UNHEALTHY’?: Gluten-free alternatives are generally considered to be less nutritionally adequate that their gluten-containing counterparts. However, food manufacturers are increasingly investing in research and development to create new gluten-free products using higher quality raw ingredients. In addition to the traditional use of maize and rice, alternative gluten-free cereals and pseudo grains - such as teff, millet, chia, amaranth, quinoa, and buckwheat - are now being incorporated. Research has shown that these enhancements have improved the taste and nutritional value of many gluten-free products, helping patients better align their diets with established healthy eating guidelines.[xiii],[xiv],[xv]
“It is crucial that we empower patients with the health literacy skills needed to choose gluten-free products that will support their overall health. Rather than focusing on individual products, we need to emphasise the importance of patients' overall dietary patterns. Gluten-free alternatives can also play an important role in allowing patients to safely participate in social events and enjoy meals that have cultural significance for them, thereby enhancing their overall quality of life”.[xvi] Mr Trott concludes.
[i] Rubio-Tapia A, Hill ID, Semrad C, et al. American College of Gastroenterology Guidelines Update: Diagnosis and Management of Celiac Disease. American Journal of Gastroenterology. 2023;118(1):59-76. doi:10.14309/ajg.0000000000002075
[ii] Laurikka P, Kivelä L, Kurppa K, Kaukinen K. Review article: Systemic consequences of coeliac disease. Aliment Pharmacol Ther. 2022;56(S1). doi:10.1111/apt.16912
[iii] Tovoli F, Negrini G, Farì R, et al. Increased risk of nonalcoholic fatty liver disease in patients with coeliac disease on a gluten-free diet: beyond traditional metabolic factors. Aliment Pharmacol Ther. 2018;48(5):538-546. doi:10.1111/apt.14910
[iv] Ciccone A, Gabrieli D, Cardinale R, et al. Metabolic Alterations in Celiac Disease Occurring after Following a Gluten-Free Diet. Digestion. 2019;100(4):262-268. doi:10.1159/000495749
[v] Lebwohl B, Cao Y, Zong G, et al. Long term gluten consumption in adults without celiac disease and risk of coronary heart disease: prospective cohort study. BMJ. 2017;357:j1892. doi:10.1136/bmj.j1892
[vi] Melini V, Melini F. Gluten-Free Diet: Gaps and Needs for a Healthier Diet. Nutrients. 2019;11(1):170. doi:10.3390/nu11010170
[vii] Barone M, Iannone A, Cristofori F, et al. Risk of obesity during a gluten-free diet in pediatric and adult patients with celiac disease: a systematic review with meta-analysis. Nutr Rev. 2023;81(3):252-266. doi:10.1093/nutrit/nuac052
[viii] Bischoff SC, Ockenga J, Eshraghian A, et al. Practical guideline on obesity care in patients with gastrointestinal and liver diseases – Joint ESPEN/UEG guideline. Clinical Nutrition. 2023;42(6):987-1024. doi:10.1016/j.clnu.2023.03.021
[ix] Vereczkei Z, Farkas N, Hegyi P, et al. It is high time for personalized dietary counseling in celiac disease: A systematic review and meta-analysis on body composition. Nutrients. 2021;13(9). doi:10.3390/nu13092947
[x] Kabbani TA, Kelly CP, Betensky RA, et al. Patients with celiac disease have a lower prevalence of non-insulin-dependent diabetes mellitus and metabolic syndrome. Gastroenterology. 2013;144(5):912-917.e1. doi:10.1053/j.gastro.2013.01.033
[xi] Kylökäs A, Kaukinen K, Huhtala H, Collin P, Mäki M, Kurppa K. Type 1 and type 2 diabetes in celiac disease: Prevalence and effect on clinical and histological presentation. BMC Gastroenterol. 2016;16(1):1-7. doi:10.1186/S12876-016-0488-2/TABLES/3
[xii] Yuan S, Leffler D, Lebwohl B, et al. Coeliac disease and type 2 diabetes risk: a nationwide matched cohort and Mendelian randomisation study. Diabetologia. Published online May 21, 2024. doi:10.1007/s00125-024-06175-8
[xiii] Allen B, Orfila C. The Availability and Nutritional Adequacy of Gluten-Free Bread and Pasta. Nutrients. 2018;10(10):1370. doi:10.3390/nu10101370
[xiv] Mármol-Soler C, Matias S, Miranda J, et al. Gluten-Free Products: Do We Need to Update Our Knowledge? Foods. 2022;11(23):3839. doi:10.3390/foods11233839
[xv] Tilley M, Jeanes Y, Spitale A, et al. Calcium and Iron Content of Cereal-Based Gluten-Free Products. Published online 2022. doi:10.3390/foods11142001
[xvi] Rinninella E, Cintoni M, Raoul P, et al. The healthy gluten-free diet: Practical tips to prevent metabolic disorders and nutritional deficiencies in celiac patients. Gastroenterol Insights. 2021;12(2):166-182. doi:10.3390/GASTROENT12020015