Manufacturers make kidney supplements from cow or pig organ tissue. The supplements deliver naturally occurring vitamins, minerals, and peptides.
People have long taken glandular kidney products for general wellness. Controlled studies have not confirmed that they directly affect human kidney function. They supply nutrients like B vitamins, iron, and CoQ10 from whole food.
Doses vary by product. Most labels suggest one to two capsules daily with a meal. Quality and purity differ across brands.
Because of their high purine content, these supplements can trigger gout flares. Heavy metal contamination is another concern. Safety during pregnancy and nursing has not been established.