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Abstract: PO2033

Protein Supplements and Proteinuria: A Case-Control Study in Military Candidates

Session Information

Category: Health Maintenance, Nutrition, and Metabolism

  • 1300 Health Maintenance, Nutrition, and Metabolism


  • Marques, Sofia H., Hospital Militar Polo Porto, Porto, Porto, Portugal
  • Freitas, Alberto, Faculty of Medicine of the University of Porto, Porto, Portugal

Man has long wanted to improve both image and physical performance using supplements some of which include proteins. Low protein diets are recommended by guidelines to attenuate the progression of chronic kidney disease. In healthy individuals, however, protein intake does not seem a risk factor. This study addressed whether protein supplements could cause proteinuria in a healthy population.


We performed a case-control study at the Military Hospital of Oporto including 1541 military academy candidates who had urinalysis in 2017. Among them, 102 (6.6%) had proteinuria (dipstick test ≥+/+++) and these were compared to a random sample of 106 non-proteinuric candidates. Telephone interviews collected data on comorbidities, exercise, smoke, alcohol habits, drugs, supplements, height and weight. Protein supplements were accessed as risk factors for proteinuria using the Pearson Qui-square test.


Answers were obtained from 49 cases and 52 controls. Of these 101 candidates, 88 were males, had a median age of 19 and mean body mass index of 24.1±2.4kg/m2. Most (97%) exercised for a mean weekly time of 6±3.7h: 40% practiced only resistance training; the rest both resistance and strength. Half used supplements at some point in time and 32 were current users. All used protein powder, mainly whey protein. Additional supplements (mostly amino acids) were used by 13. The weekly powder dose ranged from 3 to 14 scoops (20-30g/scoop). No significant association was found between the use of protein supplements and proteinuria (p=0.51). Similarly, no difference was found in creatinine, urea or other laboratory parameters. Supplements were significantly used more by those who practiced strength, as compared with resistance-training subjects.


One third of Portuguese military candidates used protein supplements. Increased use was noted in strength training most likely due to peer pressure. Proteinuria was found in 6.6%, similar to screenings in other healthy populations. No relation was found between protein supplements and proteinuria which could mean that the kidneys of healthy individuals are capable of dealing with a higher metabolic strain after increasing protein loads. However we acknowledge that proteinuria as a marker of disease has limitations and that the cumulative exposure and longtime impact of protein supplements was not considered and may be relevant.