In hypothyroidism, which lipid abnormality is commonly observed?

• A. Decreased total cholesterol
• B. Increased total cholesterol
• C. Decreased HDL
• D. Increased HDL

Answer: (B)

Thyroid hormones play a major role in lipid metabolism, boosting LDL receptor activity and promoting clearance of LDL cholesterol from the blood, as well as supporting the conversion of cholesterol to bile acids. When thyroid hormone is deficient in hypothyroidism, these processes slow down. The liver clears LDL less efficiently, so cholesterol accumulates in the bloodstream, increasing total cholesterol. Bile acid synthesis also decreases, further contributing to higher circulating cholesterol. Clinically, hypothyroidism often presents with hyperlipidemia, particularly elevated total cholesterol with a rise in LDL; triglycerides may be mildly increased and HDL can be normal or low, but the most consistent finding is increased total cholesterol.