Final answer:
People may have high cholesterol due to genetics, such as familial hypercholesterolemia, or from the body's own cholesterol production. Lifestyle factors like consuming saturated and trans fats, lack of physical activity, and smoking can also contribute to high LDL cholesterol levels despite dietary changes.
Step-by-step explanation:
Some people may continue to have high cholesterol even after eliminating cholesterol-rich foods from their diet due to different factors such as genetics, their body's production of cholesterol, and lifestyle choices. Familial hypercholesterolemia (FH) is an example of a genetic condition that can lead to high cholesterol levels. Additionally, the body naturally produces cholesterol, needed for vitamin D, hormones, and cell membranes, and this endogenous production can be influenced by dietary intake as well as by inherited characteristics.
It's important to understand that cholesterol management involves more than just dietary sources of cholesterol. Saturated fats and trans fats found in processed and fried foods also contribute to elevated LDL, or bad cholesterol, levels. Therefore, the USDA recommends limiting high-fat foods and focusing on a diet that includes plenty of fruits, vegetables, lean meats, whole grains, and unsaturated fats.
Physical activity plays a significant role in balancing cholesterol levels by lowering LDL (bad) cholesterol and increasing HDL (good) cholesterol. Smoking cessation is also critical as it affects these cholesterol levels adversely. Despite reductions in dietary cholesterol, if a person engages in other lifestyle behaviors that promote high cholesterol, such as lack of exercise or smoking, they may still experience high cholesterol levels.