Zinc lowers high-density lipoprotein-cholesterol levels

Area of Science:

• Human nutrition and metabolism.
• Cardiovascular health and disease.
• Trace element research.

Background:

• Zinc's role in cholesterol metabolism is not fully understood.
• Previous studies in rats indicated zinc increases serum cholesterol.
• The impact of zinc on human lipoprotein profiles requires investigation.

Purpose of the Study:

• To investigate the effects of zinc sulfate supplementation on serum lipoprotein concentrations in healthy adult men.
• To determine if zinc administration influences levels of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides.

Main Methods:

• A controlled study involving twelve healthy adult men.
• Participants ingested 440 mg of zinc sulfate daily for five weeks.
• Serum lipid profiles, including HDL-C, LDL-C, and triglycerides, were measured before and after supplementation.

Main Results:

• A significant 25% decrease in high-density lipoprotein-cholesterol (HDL-C) was observed (from 40.5 to 30.1 mg/dL).
• No significant changes were found in total cholesterol, triglyceride, or low-density lipoprotein-cholesterol (LDL-C) levels.
• The reduction in HDL-C suggests a potential adverse effect of zinc on lipid metabolism.

Conclusions:

• Zinc administration in humans led to a significant reduction in HDL-C, considered an "antiatherogenic" lipoprotein.
• These findings challenge previous assumptions and suggest that zinc ingestion might be atherogenic in humans.
• Further research is warranted to elucidate the mechanisms and clinical implications of zinc's impact on cardiovascular health.