From the Guidelines
Zinc supplementation should not be routinely administered to adults with chronic kidney disease (CKD) 1-5D, as there is little evidence that it improves nutritional, inflammatory, or micronutrient status. The effect of zinc on kidney function is complex and can vary depending on the dosage and individual health status. While zinc has antioxidant properties that can help reduce oxidative stress and inflammation in the kidneys, potentially slowing the progression of kidney disease, excessive intake can be harmful and impair kidney function 1.
Key considerations for zinc supplementation in patients with kidney disease include:
- Dosage: Moderate zinc supplementation (15-45 mg daily) may be beneficial, but excessive intake (above 100 mg daily) can cause harm.
- Individual health status: Patients with zinc deficiency or specific kidney conditions may benefit from supplementation, but those with existing kidney disease should consult their healthcare provider before starting supplements.
- Monitoring: Blood levels of zinc should be monitored in patients with advanced kidney disease who take supplements to avoid toxicity.
- Form of supplementation: Zinc gluconate or zinc citrate are typically well-absorbed and cause less gastrointestinal discomfort than other forms.
However, according to the most recent guideline, the routine supplementation of zinc is not recommended for adults with CKD 1-5D due to the lack of evidence supporting its benefits 1. This recommendation prioritizes the potential risks associated with zinc supplementation, particularly in patients with compromised kidney function, and emphasizes the importance of individualized care and monitoring.
From the Research
Effect of Zinc on Kidney Function
- Zinc is an essential trace element necessary for growth and cell division, and its deficiency may affect the antioxidant defense system and is related to renal failure 2.
- Zinc supplementation may be recommended only in patients with proven zinc deficiency, but its use in all chronic renal failure patients is questionable 2.
- Studies have shown that zinc deficiency is commonly encountered in chronic kidney disease (CKD) and is associated with the progression of CKD 3, 4.
- Lower baseline plasma zinc levels have been linked to a faster decline in renal function in CKD patients, although this relationship may be influenced by other factors such as age, gender, diabetes, and hypertension 3.
Zinc Supplementation and Kidney Function
- Zinc supplementation may be beneficial for nutritional status in children and adolescents with CKD, with positive effects on body mass index (BMI) Z-score, serum albumin, and C-reactive protein (CRP) levels 5.
- However, the effect of zinc supplementation on kidney function in adults with CKD is less clear, and further studies are needed to elucidate the underlying mechanisms and potential benefits of zinc supplements in CKD 3, 4.
- A meta-analysis of studies on serum zinc levels in CKD and hemodialysis patients found that both groups had lower serum zinc levels compared to healthy controls, and that hemodialysis may affect serum zinc levels 6.
Zinc Levels and Kidney Disease
- Serum zinc levels are often lower in CKD and hemodialysis patients compared to healthy controls, and may be influenced by factors such as dietary restrictions, anorexia, and hemodialysis 6.
- The relationship between zinc levels and kidney disease is complex, and further research is needed to understand the role of zinc in CKD and its potential as a therapeutic target 3, 4, 6.