Background: High protein intake has been linked to kidney growth and function. Whether protein intake is related to kidney outcomes in healthy children is unclear. Methods: We examined the associations between protein intake in infancy and kidney outcomes at age 6 years in 2968 children participating in a population-based cohort study. Protein intake at 1 year was assessed using a food-frequency questionnaire and was adjusted for energy intake. At age 6 years we measured the kidney volume and urinary albumin/creatinine ratio (ACR) of all participating children, and we estimated glomerular filtration rate (eGFR) using serum creatinine and cystatin C levels. Results: In models adjusted for age, sex, body surface area, and sociodemographic factors, a higher protein intake was associated with a lower ACR and a higher eGFR but was not consistently associated with kidney volume. However, after further adjustment for additional dietary and lifestyle factors, such as sodium intake, diet quality, and television watching, higher protein intake was no longer associated with kidney function. No differences in associations were observed between animal and vegetable protein intake. Conclusions: Our findings show that protein intake in early childhood is not independently associated with kidney size or function at the age of 6 years. Further study is needed on other early life predictors of kidney size and function in later life.
Bibliographical noteFunding Information:
The Generation R Study was supported by Erasmus Medical Center, Rotterdam; Erasmus University, Rotterdam; the Dutch Ministry of Health, Welfare and Sport; the Netherlands Organization for Health Research and Development (ZonMw). VWVJ received an additional grant from ZonMw (VIDI: 016.136.361). The authors TV, JCKJ, OHF, and EHH work in ErasmusAGE, a center funded by Nestlé Nutrition (Nestec Ltd.), Metagenics Inc., and AXA. The funders had no role in design and conduct of the study, the collection, management, analysis, and interpretation of the data, or in the preparation, review, or approval of the manuscript.
© 2015, The Author(s).
- Dietary protein
- Kidney development
- Kidney function
- Kidney volume