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Short Summary
Main recommendation: Dr. Westman argues, based on his clinical experience and review of the literature, that a keto or low-carb diet is not harmful to kidney function, and that the belief otherwise lacks supporting evidence in the medical literature. Dr. Eric Westman says the concern comes from a prejudgment that protein is bad for the kidneys, and that a properly formulated keto diet, built on real food, can be used even by some people with kidney disease, including dialysis patients, but only with close medical monitoring.
Key Points
- The fear traces back to a long-taught assumption that dietary protein harms kidneys, which Westman says has no supporting evidence in the medical literature when looked for directly.
- Westman says keto does not have to be high-protein or high-fat: it means adequate protein while running on fat and ketones, built on real food with added oils and butter used mainly in cooking.
- Westman says there's no evidence that keto worsens any stage of chronic kidney disease, and mentions a Duke colleague is analyzing clinical data from thousands of patients, with preliminary results looking fine but not yet published.
- He reports clinical observations of some people with diabetes-related kidney problems improving on keto, but stresses these need published studies before he would argue the point with other doctors.
- On kidney stones, Westman cites a study by his colleague Dr. Yancey comparing keto with low-fat diets (one stone in each group of a couple hundred people) and says the rate appears similar, while noting early stones can pass when starting any diet that increases fluid flow.
Details Worth Noting
- Concrete instructions: Keto is described as a real-food program: adequate protein, fats and ketones as fuel rather than sugar and carbs, oils and butter added during cooking rather than extra fats, and no need for a high-protein or high-fat approach.
- Concrete instructions: Anyone with kidney, liver, or heart disease, or who is on dialysis or diuretics ("fluid pills"), should do keto under medical monitoring with someone who understands salt and fluid balance; Westman says he often starts with a low-sodium recommendation carried over from the patient's prior care.
- Concrete instructions: People with no medical problems generally do not need to restrict salt on keto, and may need to add salt because the body excretes sodium more readily than on a carbohydrate diet.
- Concrete instructions: To reduce kidney stone risk, especially after a previous stone, drink plenty of fluids and keep urine flowing, particularly in hot weather or when sweating.
- Concrete instructions: For people with two or more kidney stones, Westman suggests seeing a kidney stone specialist, having urine analyzed, adjusting diet, and possibly using supplementation to prevent recurrence.
- Dialysis patients: Westman says keto has been used with dialysis patients under close monitoring, including weight checks at each visit (typically three times weekly for hemodialysis) and watching sodium and phosphate.
- Reversibility: Westman distinguishes reversible kidney changes (for example, diabetes-driven) from irreversible ones, saying some diabetes-related kidney problems may reverse on keto.
Bottom Line
The speaker presents keto as broadly safe for kidney function and ties most fears to untested assumptions, but he concedes much of his clinical support is observational and calls for published studies. People with existing kidney or related medical conditions should treat the advice as something to discuss with a physician who monitors them.
