Evidence of poor vitamin status in coeliac patients on a gluten‐free diet for 10 years

Abstract

SUMMARYBackground: Patients with coeliac disease are advised to keep to a lifelong gluten-free diet to remain well. Uncertainty still exists as to whether this gives a nutritionally balanced diet. Aim: To assess the vitamin nutrition status of a series of coeliac patients living on a gluten-free diet for 10 years. Methods: Thirty adults with coeliac disease (mean age, 55 years; range, 45-64 years; 60% women), in biopsyproven remission following 8-12 years of dietary treatment, were studied. We measured the total plasma homocysteine level, a metabolic marker of folate, vitamin B-6 and vitamin B-12 deficiency, and related plasma vitamin levels. The daily vitamin intake level was assessed using a 4-day food record. Normative data were obtained from the general population of the same age.Results: Coeliac patients showed a higher total plasma homocysteine level than the general population, indicative of a poor vitamin status. In accordance, the plasma levels of folate and pyridoxal 5¢-phosphate (active form of vitamin B-6) were low in 37% and 20%, respectively, and accounted for 33% of the variation of the total plasma homocysteine level (P < 0.008). The mean daily intakes of folate and vitamin B-12, but not of vitamin B-6, were significantly lower in coeliac patients than in controls. Conclusions: Half of the adult coeliac patients carefully treated with a gluten-free diet for several years showed signs of a poor vitamin status. This may have clinical implications considering the linkage between vitamin deficiency, elevated total plasma homocysteine levels and cardiovascular disease. The results may suggest that, when following up adults with coeliac disease, the vitamin status should be reviewed.

A dietary survey to determine if patients with coeliac disease are meeting current healthy eating guidelines and how their diet compares to that of the British general population

“…This survey has highlighted the potential nutritional inadequacies in the GFD that may be contributing to the nutritional deficiencies that have been identified in patients with CD in previous studies (Bode et al, 1991;Varkonyi et al, 1992;McFarlane et al, 1995;Thompson, 1997Thompson, , 2000Grehn et al, 2001;Hallert et al, 2002). These nutritional inadequacies could be increasing patient's risk of osteomalacia, osteoporosis and bowel problems.…”

“…Differences between the estimated intakes of energy and the EAR could be due to a biased low estimate of intake due to misreporting or patients modifying their diets during the recording period. Previous studies have validated food diaries and found patients underestimate energy requirements by 25% (Grehn et al, 2001;Hallert et al, 2002). Underestimation of energy also indicates that the results are an underestimation of all the nutrients and this need to be considered when interpreting all of the results.…”

“…A good clinical response is usually seen with the GFD; however, a number of authors have reported evidence of persisting nutritional deficiencies (Bardella et al, 1985;Collins et al, 1986;Bode et al, 1991;Varkonyi et al, 1992;McFarlane et al, 1995;Thompson, 1997Thompson, , 2000Grehn et al, 2001;Hallert et al, 2002). Often the continued ingestion of small amounts of gluten is held responsible for this.…”

“…Often the continued ingestion of small amounts of gluten is held responsible for this. However, lower body weight and body mass index, and poor vitamin status could not be attributed to malabsorption as normal intestinal permeability has been found (Bardella et al, 2000;Hallert et al, 2002). Therefore, it is possible that it is the GFD itself that could be causing these deficiencies by not providing adequate nutrition.…”

The development of a composition database of gluten-free products

“…Conversely, other authors showed significantly lower energy (6,16) and fibre intakes (17,18) , but higher intakes of total and saturated fat (16) in the diet of coeliac patients compared with healthy controls. In relation to micronutrient intakes, the majority of studies showed lower levels of folate, niacin, vitamin B 12 , vitamin E, vitamin A, P, Ca, Zn and Se in coeliac individuals than in controls (8,9,(17)(18)(19)(20) . As a consequence, despite the relatively abundant literature on the dietary habits of coeliac individuals, it is still difficult to draw a conclusion on the nutritional adequacy of the GF diet.…”