EP392: HDL, Vitamin D, and Triglycerides

Welcome to my podcast. I am Doctor Warrick Bishop, and I want to help you to live as well as possible for as long as possible. I’m a practising cardiologist, best-selling author, keynote speaker, and the creator of The Healthy Heart Network. I have over 20 years as a specialist cardiologist and a private practice of over 10,000 patients. Podcast Summary Introduction Dr. Warrick Bishop, a cardiologist, author, and CEO of the Healthy Heart Network, hosts this episode dedicated to helping Australians understand cardiovascular health. With heart disease claiming one life every 20 minutes in Australia, Dr. Bishop focuses on educating listeners about preventable risk factors. This episode explores three interconnected topics: HDL cholesterol function, vitamin D's role in bone health, and triglycerides as metabolic health indicators. Key Takeaways: HDL cholesterol's protective benefits depend on functionality, not just quantity—some people with genetically high HDL levels have dysfunctional particles that increase inflammation and cardiovascular risk rather than reducing it. Drugs developed to raise HDL cholesterol have not demonstrated clear reductions in heart attack rates, suggesting that simply elevating HDL levels is insufficient without ensuring particle function. Vitamin D does not directly build bone but instead facilitates calcium absorption in the gut, making it available for osteoblasts (bone-building cells) to use during bone formation. Vitamin D serves a paradoxical role by both supporting bone building through calcium availability and removing calcium from bones to maintain critical blood calcium levels. Triglycerides are the body's primary fat transport mechanism and rise significantly when carbohydrates (including sugar) and alcohol are consumed, as the liver converts these into triglyceride packages. High triglycerides indicate metabolic dysfunction and serve as a "canary in the mineshaft," signaling insulin resistance, fatty liver risk, prediabetes, and poor lifestyle choices. Elevated triglycerides are often accompanied by low HDL levels and trigger changes in LDL particle size from large, benign particles to small, dense particles that pose greater arterial risk. Reducing carbohydrate and alcohol intake combined with regular exercise can dramatically lower triglycerides, with omega-3 fish oil supplementation providing additional support. The total cholesterol-to-HDL ratio remains a reasonably robust predictor of cardiovascular risk for most people, though individual variations exist. Dr. Bishop's forthcoming book "Cholesterol Explained" (mid-2025) addresses myths surrounding cholesterol, statins, and cardiovascular disease in greater detail.