Background and aims: Both obesity and iron deficiency are public health problems. The association between the two problems could be explained by chronic low-grade inflammation in obesity, which could stimulate hepcidin expression and modify iron concentration that the consumption of high-protein diets could prevent. Thus, this study aimed to compare the effects of high-protein diets with a predominance of animal or vegetable protein on serum hepcidin and iron concentrations in adults with obesity.
Methods and results: This randomized clinical trial involved adults with obesity and insulin resistance, who were assigned to either a high animal protein (AP) group or a high vegetable protein (VP) group for a one-month intervention. Both groups followed a calorie-restricted diet, reducing energy intake by 750 kcal/day. Baseline and final measurements included serum concentrations of hepcidin and iron, biochemical parameters, anthropometric data, and body composition. A total of 33 participants (63 % female) were included in the study. Significant weight loss was observed in both groups after the intervention. Adjusted for weight loss percentage, the AP group showed a significant increase in hepcidin concentration (from 22.3 ± 14.7 to 27.5 ± 19.5 ng/mL) compared to the VP group (from 17.9 ± 15.1 to 17.2 ± 10.1 ng/mL) (p < 0.01), with no changes in serum iron concentration. Additionally, the VP diet significantly reduced serum adiponectin (p = 0.04) and C-reactive protein (p = 0.03) levels.
Conclusions: In adults with obesity following the AP diet for one month, hepcidin levels increased without affecting serum iron concentrations.
Trial registration: NCT03627104.
Keywords: Diet; Hepcidin; Iron; Obesity; Protein.
Copyright © 2024 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.