More than 37 million American adults have chronic kidney disease (CKD), and 90% don’t know it until blood tests show trouble.
Many reach for vitamins and supplements thinking they’re supporting health, yet certain ones — even popular, over-the-counter choices — can quietly add stress to already struggling kidneys.
The problem isn’t vitamins in general; it’s that damaged kidneys process some nutrients very differently than healthy ones.
Keep reading for the six supplements most nephrologists want CKD patients to discuss before taking — plus safer ways to get the benefits you’re looking for.
Why Some Vitamins Become Risky When Kidneys Aren’t Working at 100%
Healthy kidneys carefully regulate minerals, clear waste, and activate certain vitamins.
In CKD stages 3–5, that regulation weakens, so excess amounts of fat-soluble vitamins, certain minerals, or high-dose water-soluble vitamins can build up or cause harmful side effects.
Research from the National Kidney Foundation and major journals consistently shows that personalized supplement plans — created with a doctor or renal dietitian — work far better than one-size-fits-all multivitamins.
The 6 Supplements Kidney Specialists Most Often Flag
1. High-Dose Vitamin A (retinol forms > 3,000 IU daily)
Excess preformed vitamin A (not beta-carotene from food) is linked to higher calcium levels and toxicity in CKD.
A 2022 review in Kidney International Reports noted increased risk of hypercalcemia and vascular calcification.
Safer choice: Get vitamin A from carrots, sweet potatoes, and spinach — your body converts only what it needs.
