MISSISSIPPI STATE -- Many people don't worry about cholesterol until they have a heart attack, but a little concern beforehand often can prevent many problems.

Dietary cholesterol is necessary for the body to function normally, but too high levels of these fats in the blood can be deadly.

Linda Patterson, health education specialist with Mississippi State University's Extension Service, said the imbalance of blood lipids -- fats -- raises the risk of heart disease. Things such as stress, genetics and exercise all affect the amount of blood fat.

"Everyone should know their cholesterol levels and if they have an imbalance of blood fats, they need to figure out what is causing this imbalance," Patterson said.

The body uses blood fats in the lining of membranes and to build and repair tissue. The problems include both excess amounts of total and LDL -- bad -- cholesterol, and too low levels of HDL -- good -- cholesterol.

"High density, good cholesterol helps the body get rid of extra low density lipids, but any that is left can clog the arteries," Patterson said.

High levels of blood fats can lead to atherosclerosis, the process of fatty deposits blocking the arteries, Patterson said. Risk factors for heart disease and stroke include family history, tobacco use, elevated cholesterol levels, physical inactivity and elevated blood pressure.

Dr. Melissa Mixon, Extension human nutrition specialist, said most people can avoid blood fat problems by eating right and exercising.

"Under normal circumstances, your body successfully regulates itself so that cholesterol needs are met between what is eaten in food and what the body makes in the liver," Mixon said.

The American Heart Association recommends eating less than 300 milligram per day of cholesterol and keeping blood cholesterol levels below 200 milligrams/deciliter.

While all animal products contain cholesterol, eggs and organ meat have the highest levels. Just because a food is high in cholesterol does not mean it must be completely cut out of diets.

"There are no bad foods if they are eaten in moderation," Mixon said.

Eggs contain cholesterol but are valuable sources of protein, B vitamins, iron and other minerals essential to good health. Pork and beef, often avoided by those concerned about heart disease, can be healthy if certain cuts are used. "With both red meat and pork, anything with a loin or round cut is considered lean meat," Mixon said. "Serving sizes should not exceed 6 ounces of cooked meat or poultry each day."

Although cholesterol has received much negative attention, saturated fats are actually the chief cause of raised levels of blood fats. Mixon said saturated fats in the diet play a more significant role in increasing the individual's risk of developing heart disease than does cholesterol in the diet.

But while heart disease is the leading cause of death among Americans, many still are not concerned with blood fat levels.

"A very low percentage of Americans who are healthy and try to prevent heart problems actually follow the guidelines they should, and it is estimated that only about 50 percent of those with heart disease follow the guidelines," Mixon said.

Information is available online from the American Heart Association at http://www.amhrt.org on determining risks and reducing these, eating right and more.