First Course DASH, Second Course Mediterranean: Comparing Renal Outcomes for Two "Heart-Healthy" Diets

To review studies evaluating renal outcomes based on patient adherence to the Mediterranean diet or to the Dietary Approaches to Stop Hypertension (DASH) diet and to determine which diet is most effective in preventing and managing renal disease.

Both the DASH and Mediterranean diets have shown many health benefits, including reduced risk for chronic kidney disease (CKD), nephrolithiasis, mortality due to all renal causes and composite outcomes. Both diets have shown a decrease in estimated glomerular filtration rates (eGFR) decline with a concomitant improvement in mortality and dialysis initiation. In summary, both diets resulted in similar magnitudes of risk reduction when comparing equivocal levels of adherence to each diet. Review of evidence for renal outcomes shows strikingly similar effects for both DASH and Mediterranean diets. We hypothesize that these results are due to the overlap in nutritional composition. Both encourage whole foods such as fruits, vegetables, beans/legumes, whole grains, and nuts. Additionally, they restrict animal protein consumption and limit processed and fast foods. Determining a nutritional management intervention for renal impairment is clinically important as approximately 1% of the USA annual budget is spent on end stage renal disease (ESRD) treatment. We believe either diet could be incorporated into a patient's management when considering their renal health. In conclusion, we urge physicians to help patients choose either the DASH diet or Mediterranean diet based on the patient preference.