What do people with cystic fibrosis eat? Diet quality, macronutrient and micronutrient intakes (compared to recommended guidelines) in adults with cystic fibrosis–A systematic review

Background: Treatment advancements have improved life expectancy and nutritional status of people with cystic fibrosis (CF). Alongside reductions in malnutrition, incidences of overweight, obesity and risk factors for diet-related chronic diseases have increased in recent years. This study aimed to synthesise the available literature on diet quality, macronutrient and micronutrient intakes compared to the recommended guidelines in adults with CF, an essential step in deducing the optimal dietary pattern and intakes for CF adults. Methods: A systematic search of five electronic databases from inception until April 2023 was conducted using keywords related to CF, diet quality and nutrient intakes. Results: Twenty-one studies were included comprising 18 cross-sectional, one cohort and two case control studies, reporting data from 724 adults with CF. Energy and / or macronutrient intake data was reported across 17 cohorts, eight studies provided micronutrients data, and diet quality was determined for four CF cohorts by using a diet quality score, and / or categorising food intake into servings per day for food groups and comparing findings to national dietary guidelines. Although energy intake recommendations were met, and most micronutrient requirements were achieved through supplementation, total energy intake from fat was above recommendations and diet quality was poor. Conclusion: This is the first systematic review comprehensively evaluating literature on dietary intakes of adults with CF. Energy-dense, nutrient-poor foods contribute to intakes which pose risk in developing diet-related chronic diseases. Revision of dietary guidelines and practice change in CF nutritional therapy is warranted to optimise nutrition and health outcomes.