In some chronic kidney disease (CKD) patients, protein restriction has been shown to prolong kidney function and minimize some of the metabolic consequences of uremia. Dietary restrictions will vary based on the patient's kidney function, concomitant illness, medication use, fluid status, presence of hypertension, appetite, and general food consumption patterns.
General recommendations from the Modification of Diet in Renal Disease study suggest patients with a glomerular filtration rate (GFR) 25 to 55 mL/min/1.73 m2 consume at least 0.8 g of protein per kg/d. For those with a GFR < 25 mL/min/1.73 m2 and not yet on dialysis, 0.6 g/kg/d is recommended.1, 2, 3, 4 At least 50% of the dietary protein should be of high biologic value (HBV). Close consideration should be taken to ensure adequate caloric intake as inadequate caloric intake can mitigate the potential benefit of a low-protein diet (ingested protein may be catabolized for energy).
Caloric needs of predialysis patients parallels that of normal healthy persons.5 However, unlike the general population, predialysis patients tend to have poor intakes and may begin to show clinical signs of malnutrition by the time dialysis is started. The daily calorie intake recommended is 35 kcal/kg of ideal body weight for individuals < 60 years old and, for those 60 or older, 30 to 35 kcal/kg.2 Obese patients require less calories at 20 to 30 kcal/kg adjusted body weight. Underweight patients require more calories per day at 45 kcal/kg desired body weight.
The primary source of energy should be from complex carbohydrates with fat comprising approximately 30% to 40% of the total energy intake. Fats should be primarily from monounsaturated and polyunsaturated sources.
Ensuring adequate calories on a low-protein diet can be quite challenging for the patient. There are many products on the market that can help the patient meet their caloric requirements while following this diet. Table 1 lists the nutrition composition of various low protein products currently available from Ener-G Foods, Inc (Seattle, WA), Med-Diet (Plymouth, MN), Cambrooke Foods (Framingham, MA) and Scientific Hospital Supplies (Gaithersburg, MD).
*Results gained from individual analyses cannot be declared as average or typical due to batch-to-batch variation and values being so close to the limit of detection.
These products can be used as supplied or as in the case of the all-purpose baking mix, it can be used in lieu of regular flour to make bread, pancakes, cookies, or brownies. The chocolate bars can be consumed as a high-energy snack or melted as a fruit dip or drizzled over baked goods. World wide web addresses are listed as most sites will provide ordering and pricing information, detailed description of products, serving suggestions, recipes, and storage instructions.
References
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1
Mitch W.
Dietary therapy in uremia: The impact on nutrition and progressive renal failure. Kidney Int. 2000;57:S38–S43.
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2
NKF-DOQI .
Clinical Practice Guidelines for Nutrition. New York, NY: National Kidney Foundation; 2000;.
3.
3
Striker G.
Report on a workshop to develop management recommendations for the prevention of progression in chronic renal disease. J Am Soc Nephrol. 1995;5:1537–1540. MEDLINE
4.
4
Kopple J, Levey A, Greene T, et al.
, Modification of Diet in Renal Disease Study Group Effect of dietary protein restriction on nutritional status in the modification of diet in renal disease study. Kidney Int. 1997;52:778–791. MEDLINE |
CrossRef
5.
5Goldstein DJ, McQuiston BD: Renal failure, in Contemporary Nutrition Support Practice. (in press)