Cholesterol is a fat-like substance that can accumulate along the walls of your arteries if your blood contains too much of it. These fatty deposits can reduce or stop the flow of blood, which can lead to heart disease, heart attack and stroke. Cholesterol levels rise to dangerous levels in response to a number of lifestyle factors, as well as certain health risk factors that you cannot control.
Diet
What you eat affects your cholesterol level because certain types of fat can raise the amount of cholesterol circulating in your blood. Saturated fat from animal products, like meat, poultry or dairy, is the worst culprit, according to the National Heart Lung and Blood Institute. Saturated fat raises the level of low-density lipoprotein, or "bad" cholesterol, more than anything else in your diet. LDL cholesterol is the kind of cholesterol that attaches to your artery walls and raises the risk of heart disease. Trans fats also raise cholesterol levels. Trans fats are made from hydrogenated vegetable oils and are found in margarines, fried and processed foods, as well as many commercial baked goods. Some foods contain dietary cholesterol, such as eggs, meat and cheese, which can also contribute to high blood cholesterol levels.
Being Overweight
Being overweight increases your LDL cholesterol levels, total cholesterol levels and triglyceride levels, all of which increase the risk of heart disease. It also lowers your high-density lipoprotein, or "good" cholesterol, levels so that there is less HDL cholesterol in your bloodstream to remove the LDL cholesterol from your arteries. Obesity also increases your risk of high blood pressure and Type 2 diabetes, which increases your risk of heart disease.
Lack of Exercise
A lack of exercise increases your LDL cholesterol level and raises your risk of heart disease. Regular exercise not only lowers your LDL cholesterol level but it raises your HDL levels, lowering your risk for heart disease.
Genetics
High cholesterol runs in families, so if you have a family history of the problem, you are more likely to have high cholesterol yourself. Some families have a genetic condition that causes extremely high LDL cholesterol levels from birth and this increases the risk of a heart attack at a young age.
Age and Sex
Age also affects cholesterol levels because they tend to rise as you get older. Sex is also a factor: Men tend to have lower levels of HDL cholesterol and higher levels of LDL cholesterol than women, from puberty on. When women hit menopause, their LDL levels begin to climb and from age 55 on, they have higher LDL cholesterol levels than men, according to NHLBI.
Other Factors
Some health conditions can increase the risk of high cholesterol, including diabetes, high blood pressure, stress, smoking, hypothyroidism, kidney disease, liver disease and polycystic ovary syndrome. In addition, some medications may increase the risk of high cholesterol, including steroids and progestins.
