Cholesterol is a waxy, fat-like substance present in every cell of the body, essential for several bodily functions. While some cholesterol is necessary for health, excessive amounts can lead to serious health issues. This article explores cholesterol’s functions, the impact of excess dietary cholesterol, and its health consequences.
Cholesterol’s Role and Types
Cholesterol serves several functions. It provides structure to cell membranes, helps the liver produce bile for digestion, and acts as a building block for hormones such as estrogen, testosterone, and vitamin D. The body primarily produces cholesterol in the liver, with a smaller portion from diet.
Cholesterol travels through the bloodstream within particles called lipoproteins. Two main types are Low-Density Lipoprotein (LDL) and High-Density Lipoprotein (HDL). LDL cholesterol, often called “bad” cholesterol, transports cholesterol from the liver to cells throughout the body. HDL cholesterol, known as “good” cholesterol, performs the opposite role, carrying excess cholesterol back to the liver for removal from the body, protecting arteries.
How Excess Dietary Cholesterol Impacts Your Body
The liver regulates cholesterol levels by producing and removing it from the bloodstream. When dietary cholesterol intake is high, this system can become overwhelmed, leading to an increase in circulating LDL cholesterol. The liver’s ability to process and eliminate cholesterol can be affected, potentially contributing to fat accumulation in the liver.
Excess LDL cholesterol initiates atherosclerosis, the hardening and narrowing of arteries. This begins when LDL particles accumulate within the arterial walls, leading to an inflammatory response. White blood cells consume this excess cholesterol, forming “foam cells” and fatty streaks, the earliest signs of atherosclerosis. As these streaks grow, they develop into larger plaques of cholesterol, fats, calcium, and other debris, further narrowing arteries.
The Health Consequences of High Blood Cholesterol
Prolonged high LDL cholesterol contributes to atherosclerosis progression, leading to various health complications. As plaques grow, they restrict blood flow, leading to coronary artery disease (CAD). In CAD, heart arteries narrow, potentially causing chest pain (angina) from reduced oxygen.
A heart attack, or myocardial infarction, can occur if a plaque in a coronary artery ruptures. This rupture can trigger a blood clot that completely blocks blood flow to a section of the heart, starving it of oxygen. High blood cholesterol also increases the risk of an ischemic stroke, where a blood clot blocks an artery supplying blood to the brain.
Peripheral artery disease (PAD) is another condition linked to high cholesterol, affecting arteries in the legs, arms, or pelvis. Plaque buildup in these arteries narrows them, reducing blood flow to the limbs and causing symptoms like leg pain during activity. In severe cases, PAD can lead to tissue damage and potentially amputation. High LDL cholesterol can also worsen high blood pressure, as the heart must work harder to pump blood through narrowed arteries.