Mehdi Khakian
1,2 
, Sanaz Jamshidi
3, Mitra Kazemi Jahromi
4, Ebrahim Mokhtari
5,6, Setareh Alibakhshi
1,2, Niloufar Saber
7, Reza Sadeghi
1,2, Ammar Salehi-sahlabadi
8,9, Elham Sobhrakhshankhah
10, Hossein Farhadnejad
5* , Farshad Teymoori
2* , Parvin Mirmiran
5 1 Nutritional Sciences Research Center, Iran University of Medical Sciences, Tehran, Iran
2 Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
3 Center for Cohort Study of Shiraz University of Medical Sciences Employees, Shiraz University of Medical Sciences, Shiraz, Iran
4 Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, BandarAbbas, Iran
5 Nutrition and Endocrine Research Center, Research Institute for Endocrine Disorders, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
6 Department of Community Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
7 Faculty of Health, Southern Cross University, Gold Coast, Queensland, Australia
8 Clinical Biochemistry Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
9 Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
10 Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran
Abstract
Introduction: Non-alcoholic fatty liver disease (NAFLD) represents a rising global health challenge, marked by excessive fat deposition in the liver. The present case-control study sought to examine the relationship between intake of ultra-processed foods (UPFs) and the risk of NAFLD.
Methods: Out of 1000 invited individuals, this case-control study included 225 newly diagnosed NAFLD cases (confirmed via ultrasound) and 450 controls (aged 20–60 years) who underwent ultrasound screening to rule out hepatic steatosis. A validated food frequency questionnaire was used to assess dietary intake, and UPF consumption was quantified both as grams per day and as a percentage of total daily energy intake.
Results: The mean (SD) daily UPF consumption amounted to 147.5 (117.4) g, representing 15.4 (7.98)% of total energy intake. After adjusting for potential confounders, UPF intake (kcal/d) showed a positive association with odds of NAFLD (OR=5.91; 95%CI: 2.96–11.78; P for trend<0.001). A one-SD rise in UPF intake (SD=221 kcal/d, roughly equivalent to 117.4 g/d of UPF) was linked to higher NAFLD odds (OR=1.96; 95% CI: 1.63–2.41; P for trend<0.001). When UPF intake was considered as a percentage of energy, the multivariable model revealed elevated NAFLD odds across tertiles (OR=2.27; 95% CI: 1.26–4.10; P for trend<0.001). In the fully adjusted model, each one-SD increment in UPF intake (SD=7.98% of energy/day) was significantly associated with increased odds of NAFLD (OR=1.29; 95%CI: 1.03–1.62; P for trend<0.001).
Conclusion: A higher consumption of UPF may be related to increased odds of developing NAFLD.