Children with coeliac disease (CD) may be at risk of nutritional deficiencies because of the restrictiveness of following a life-long gluten free diet. Gluten-free products may have different nutritional compositions compared with gluten-containing equivalents, including lower fibre and higher fat contents, with significant variation between different brands. Previous studies evaluating the dietary intake of children with CD have reported conflicting results and have been limited by comparisons with non- or inadequately matched controls. This cross-sectional, case-control study aimed to evaluate the nutritional intake of children with CD following a gluten-free diet, compared with health controls (HC). As a secondary aim, the relationship between dietary composition and socioeconomic factors was also investigated.
Methods
Subjects were recruited between 2015-2017 from Sydney Children’s Hospital, Australia. Inclusion criteria were: children aged 2-18 years with histologically confirmed CD, and adherent to a gluten-free diet for minimum 6 months. Healthy controls were defined as children without any acute or chronic diseases, which would alter their dietary patterns. Dietary intake was assessed through a validated semi-quantitative food frequency questionnaire. Socioeconomic status was quantified by calculating the Index of Relative Socioeconomic Disadvantage (IRSD) using participants postcodes.
Key findings
- Sixty five CD subjects and 65 HC were available for final analyses. The mean age of participants was 10.2 years for CD cases and 10.1 years for HCs, with 38.5% of each group being male gender. The mean duration of gluten-free diet was 3.6 years (range = 0.5-12.6 years).
- Children with CD had a higher energy intake (p=0,02) and higher intake of total fat (p=0.003), compared to the HC group. These finding agree with many previous studies. Intakes of sub-types of fat were also higher in children with CD, which suggests that the distribution of energy intake across the fat subtypes was similar between the two groups (ie children with CD likely ate similar fat-containing food items, but they ate more). This is in keeping with findings from previous studies.
- There was no significant difference in protein and carbohydrate intake between the two groups. The relative contribution of protein, fat and carbohydrate to total energy intake and the relative contribution of saturated, polyunsaturated and monounsaturated fat were similar with no significant differences observed.
- There was also no significant difference in sugar and fibre intake between children with CD and HC. The lack of difference in fibre intake agreed with previous studies, even though historically, children on a gluten-free diet were thought to be at greater risk of insufficient fibre intake because of the low fibre content of refined flours traditionally used in gluten-free foods. This is perhaps a reflection of the advancements made by the gluten-free food industry over recent years, resulting in improved nutritional profiles amongst products.
- There was no significant difference in micronutrient intake between the CD and HC groups. In both groups, intakes of micronutrients met the recommended dietary intake or average intake in most children. There were no differences noted in the various dietary measures between children with CD of relative socioeconomic disadvantage and relative socioeconomic advantage, the same was true for HCs.
- Children with CD had significantly lower mean weight (p=0.003) and BMI z-scores (p=0.02) compared to HCs. This may indicate that changes in body composition and growth in untreated CD patients do not completely reverse after establishment of a gluten-free diet. There was no significant difference in height z-scores between CD and HC groups. There was no correlation between weight, BMI and height z-scores and duration of time on a gluten-free diet.
The authors of this study concluded that participants with CD consumed more calories (through consuming more dietary fat) than non-coeliac peers, whilst maintaining similar intakes of other macronutrients and micronutrients. Reassuringly, dietary intake doesn’t seem to have been impacted by socioeconomic factors. Despite consuming more calories and fat than matched controls, children with CD had lower weight and BMI z-scores.
Link to original article: https://journals.lww.com/jpgn/Abstract/2020/08000/Evaluating_the_Dietary_Intakes_of_Energy,.24.aspx