There are a few connections that have been established between obesity and cardiovascular disease; these effects tend to be more prevalent with increased weight gain, even prior to becoming obese. First, obesity tends to be directly correlated with an increase in blood pressure, which is one of the leading determinants of cardiovascular disease. In addition, obesity often increases insulin resistance in the body, which can lead to other conditions such as diabetes in addition to heart disease. Another correlation between obesity and cardiovascular disease is that being overweight is often related to higher levels of cholesterol, particularly LDL, the "bad" cholesterol.
The connection between obesity and cardiovascular disease as related to high cholesterol is one of the most commonly noted. This is because overweight people frequently have higher levels of unhealthy fats known as triglycerides in the blood, which tend to raise LDL cholesterol levels and lower HDL cholesterol levels, which is exactly opposite of the ideal. High cholesterol and triglyceride levels are excellent indicators of future heart disease, such as a heart attack; they can also lead to stroke. Weight loss can help to reverse this pattern and lower overall cholesterol and triglyceride levels.
Insulin resistance, when the body does not process glucose as well as it should, is one of the precursors to diabetes and is another connection between obesity and cardiovascular disease, since it is often seen in people who are overweight. This is indicated by a blood test that shows high blood sugar that is difficult for the body to regulate. This condition, combined with high triglycerides, causes what is known as an "inflammatory" state in the body which also makes heart disease more likely.
In addition, another one of the primary connections between obesity and cardiovascular disease is that additional weight places additional stress on the body, which increases blood pressure. This also plays a role in the inflammatory state of the body, and drastically increases the risk of heart attack or stroke. It can also lead to kidney disease, which itself also increases blood pressure. Of course, the sole predictor of cardiovascular disease is not obesity, though there is an established connection between obesity and cardiovascular disease that should be considered. Often, losing weight and increasing physical fitness under the guidance of a doctor or nutritionist can help to improve, or even reverse, some of these effects and decrease the risk of cardiovascular disease.