Except from MSc (Med) Physiology Dissertation (UCT), by Tamzyn Murphy (RD)
Safety concerns have been raised over low carbohydrate high fat (LCHF) diets’ relatively high protein content, for renal function . While protein intake on LCHF diets may be higher than on conventional diets, it seldom exceeds 30 % total daily energy intake (TDEI) [10, 101]. Critics theorise that high protein intake (> 25% of TDEI or > 2 g. kg body weight (BW)-1 ) may chronically increase glomerular pressure and hyperfiltration, thereby damaging the kidneys  – particularly concerning in Type 2 Diabetes (T2D) with its high nephropathy risk. Indeed protein restriction helps preserve renal function in pre-existing kidney disease . However, evidence doesn’t support the theory that high protein diets impair renal function in the absence of kidney disease [100, 102, 103, 105], even in obese individuals with T2D . In fact, very low carbohydrate high fat (VLCHF) diets may improve renal function , as indicated by results showing reversal of diabetic nephropathy in rodents  and reduced creatinine concentrations in an intervention study in overweight and obese humans with and without T2D .
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