From the Guidelines
Kidney supplements are not generally recommended for most people with healthy kidneys, and individuals with kidney concerns should consult a healthcare provider before taking any supplements. The most recent and highest quality study, 1, suggests that a very low–protein diet supplemented with essential amino acids or ketoacid analogs may be beneficial for adults with CKD who are at risk of kidney failure, but this should be done under close supervision.
Key Considerations
- Instead of taking supplements, focus on maintaining overall kidney function through: + Proper hydration + A balanced diet low in sodium + Regular exercise
- Certain nutrients like vitamin B6, magnesium, and potassium may support kidney function, but these should ideally come from food sources rather than supplements 2, 3.
- For those with kidney disease, many supplements can actually be harmful as damaged kidneys may not properly filter supplement ingredients, potentially worsening kidney function.
- Common supplements like cranberry extract may help prevent urinary tract infections which can affect kidney health, but they don't directly improve kidney function.
Preventative Measures
- Control blood pressure and blood sugar
- Maintain a healthy weight
- Avoid smoking
- Limit alcohol consumption
- Consult with a healthcare provider or a renal dietitian to educate individuals with CKD about dietary adaptations regarding sodium, phosphorus, potassium, and protein intake, tailored to their individual needs and severity of CKD and other comorbid conditions 4, 5.
Special Considerations
- Children with CKD stages 2 to 5 may require supplementation of vitamins and trace elements if dietary intake alone does not meet 100% of the DRI or if clinical evidence of a deficiency is present 6.
- Caution should be exercised when using supplements to not exceed the UL for the contents of the preparation when the intake of diet and supplement is combined.
From the Research
Kidney Supplements
- The use of kidney supplements, such as vitamin D and omega-3 fatty acids, has been studied in relation to kidney function and disease progression in patients with chronic kidney disease (CKD) 7, 8, 9, 10, 11.
- A randomized clinical trial published in JAMA in 2019 found that supplementation with vitamin D3 or omega-3 fatty acids did not significantly difference in change in estimated glomerular filtration rate (eGFR) at 5 years in adults with type 2 diabetes 7.
- However, a 2021 study published in the American Journal of Nephrology found that higher dietary omega-3 fatty acid intake was associated with lower all-cause mortality in patients with CKD 8.
- A 2024 review of antioxidants in CKD published in Current Medicinal Chemistry discussed the potential benefits of omega-3 fatty acids, vitamins E and C, and other antioxidants in reducing oxidative stress and cardiovascular risk in CKD patients 9.
- A 2020 systematic review and meta-analysis published in Clinical Nutrition found that omega-3 polyunsaturated fatty acid supplementation may reduce cardiovascular mortality in patients on hemodialysis, but the evidence was of low to very low certainty 10.
- A 2020 study published in Applied Physiology, Nutrition, and Metabolism found that oral supplementation with omega-3 fatty acids reduced inflammation markers in patients with CKD on hemodialysis 11.
Types of Kidney Supplements
- Omega-3 fatty acids: may reduce cardiovascular mortality and inflammation in CKD patients 8, 10, 11.
- Vitamin D: did not significantly affect eGFR in adults with type 2 diabetes 7.
- Antioxidants: may reduce oxidative stress and cardiovascular risk in CKD patients 9.