9 Vitamins & Supplements That DESTROY Your Liver & Kidneys

 

Herbal “natural”  supplements often marketed for stress relief, weight loss, menopause support, etc.

How they harm

  • Kava: has been linked to liver enzyme abnormalities, liver injury; may reduce kidney blood flow and increase harmful metabolites in kidneys.

  • Comfrey: contains pyrrolizidine alkaloids, strongly hepatotoxic.

  • Black Cohosh: associated with liver damage in some cases. Concentrated green tea extract (high catechin doses): linked to acute liver injury.

Key risk factors

  • Use of high‐dose extracts rather than customary food/herbal doses.

  • Poorly regulated products with contaminants.

  • Existing liver or kidney disease.

How to protect yourself

  • Use herbal supplements cautiously; check for reliable third-party testing.

  • Avoid high doses unless under supervision.

  • Monitor liver/kidney function if using such products.

  • Be especially cautious if also taking other liver- or kidney-stressors (alcohol, medications, etc).


7. High-dose Protein / “Protein Powders” in Overuse

What it is

Protein powders (whey, casein, plant‐based) used by athletes or fitness enthusiasts.

How it harms

  • Kidneys filter nitrogenous waste from protein metabolism. If you consume very large amounts of protein (well beyond needs) AND have dehydration or borderline kidney function, kidneys must work harder.

  • Liver processes amino acids; excessive protein may increase liver workload (though the liver is more resilient than kidney in this respect).

Key risk factors

  • Chronic very high protein intake (e.g., >2.5 g/kg body-weight daily) especially with insufficient hydration.

  • Dehydration, pre-existing kidney impairment.

How to protect yourself

  • Calculate protein needs (often ~1.2-2 g/kg for active adults) and avoid far exceeding it.

  • Stay well hydrated.

  • If you have kidney disease, get guidance from a dietitian/nephrologist.


8. Overuse of Iron or Other Minerals (Selenium, Calcium, Zinc)

What it is

Minerals are essential but in excess can cause organ damage.

How it harms

  • Iron: described above (see section 3).

  • Calcium: excess may cause kidney stones, nephrocalcinosis, and burden kidneys.

  • Selenium & Zinc: in excess can lead to toxicity, which may secondarily stress liver/kidneys (though less directly documented).

Key risk factors

  • Taking high‐dose mineral supplements without checking levels or needs.

  • Combining many supplements/mineral fortifications that unintentionally sum to high doses.

How to protect yourself

  • Test mineral levels (serum ferritin, calcium, etc) before supplementing.

  • Avoid self-diagnosis and mega dosing minerals.

  • Consider nutrient intake from food when calculating total mineral intake.

    Groceries

9. “Megavitamin” and High-Potency Multivitamin Formulas

What it is