Animal Versus Plant Protein Meals in Individuals With Type 2 Diabetes and Microalbuminuria
Effects on renal, glycemic, and lipid parameters
- Madelyn L. Wheeler, MS, RD1,
- S. Edwin Fineberg, MD1,
- Naomi S. Fineberg, PHD1,
- Reid G. Gibson, MS1 and
- Laurie L. Hackward, MS, RD2
- 1Diabetes Research and Training Center, Indiana University School of Medicine, Indianapolis, Indiana
- 2General Clinical Research Center, Indiana University School of Medicine, Indianapolis, Indiana
OBJECTIVE—To determine, for individuals with type 2 diabetes and microalbuminuria, the effects of 6 weeks of meals containing plant-based protein (PP) versus meals with predominantly animal-based protein (AP) on renal function and secondarily on glycemia, lipid levels, and blood pressure.
RESEARCH DESIGN AND METHODS—In a randomized crossover trial, we compared 6 weeks of meals containing only PP with meals containing primarily AP (60% animal, 40% plant) in 17 subjects with type 2 diabetes and microalbuminuria treated with diet and/or oral antidiabetic agents. Protein content was equivalent to the average American diet, and calories provided weight maintenance. Nutrients were equivalent between the two diets. Meals were prepared and packaged by a metabolic kitchen staff and were sent home weekly. At the beginning and end of each 6-week period, subjects were studied for 36 h on a metabolic unit.
RESULTS—There were no significant differences between diets for glomerular filtration rate, renal plasma flow, albumin excretion rate, total cholesterol, HDL cholesterol, triglyceride area under the curve (AUC), glucose and insulin AUC, HbA1c, blood pressure, or serum amino acids. For both diets, at the end of the treatment periods as compared with baseline, total cholesterol was significantly lower (PP and AP: from 4.75 to 4.34 mmol/l, P < 0.01), HbA1c had significantly improved (PP: from 8.1 to 7.5%, P < 0.01; AP: from 7.9 to 7.4%, P < 0.01), and diastolic blood pressure was significantly lower (PP: from 83 to 80 mmHg, P < 0.02; AP: from 82 to 78, P < 0.02).
CONCLUSIONS—There is no clear advantage for the recommendation of diets containing only PP rather than diets containing protein that is primarily animal-based for individuals with type 2 diabetes and microalbuminuria. There are, however, potential lipid, glycemic, and blood pressure benefits for following a carefully constructed, weight-maintaining, healthy diet, regardless of protein source.
- AER, albumin excretion rate
- AP, animal-based protein
- AUC, area under the curve
- CV, coefficient of variation
- GCRC, General Clinical Research Center
- GFR, glomerular filtration rate
- PAH, paraminohippurate
- PDCAAS, protein digestibility-corrected amino acid score
- PP, plant-based protein
- RPF, renal plasma flow
Address correspondence and reprint requests to Madelyn L. Wheeler, Indiana University School of Medicine, IF 122, 250 University Blvd., Indianapolis, IN 46202. E-mail:.
Received for publication 13 December 2001 and accepted in revised form 17 April 2002.
Additional information on this article can be found at http://care.diabetesjournals.org/.
A table elsewhere in this issue shows conventional and Système International (SI) units and conversion factors for many substances.
See accompanying editorial on p. 1474.
- DIABETES CARE