The Cardiovascular System - Taking care: keeping the cardiovascular system healthy
A healthy lifestyle is key to keeping the cardiovascular system healthy. Proper diet, regular exercise, maintaining a healthy weight, not smoking, moderate alcohol drinking, and reducing stress all lead to a healthy heart lifestyle.
A healthy diet can decrease the risk of atherosclerosis from developing, which can lead to heart disease, heart attacks, and strokes. The "Food Guide" Pyramid developed by the U.S. Departments of Agriculture and Health and Human Services provides easy-to-follow guidelines for such a diet. In general, foods that are low in fat (especially saturated fat), low in cholesterol, and high in fiber should be eaten. Fat should make up no more than 30 percent of a person's total daily calorie intake. Breads, cereals, pastas, fruits, and vegetables should form the bulk of a person's diet; meat, fish, nuts, and cheese and other dairy products should make up a lesser portion.
Q: Why do I feel lightheaded or dizzy when I get up quickly after having lain down?
A: You feel lightheaded because of changes in two related forces: gravity and blood pressure. When you are lying down, gravity is pressing equally along the length of your body. Your heart is able to maintain a constant blood pressure throughout your body by beating at a constant rate.
When you arise suddenly, however, the pressure of gravity is greater upon the upper parts of your body, especially your head. This abrupt change in pressure causes blood in the vessels in your head to flow downward, bringing about a decrease in blood pressure in those vessels. Receptors in the carotid arteries immediately sense this drop in blood pressure and signal the accelerator center in the medulla. The accelerator center then signals the heart to increase the rate of contraction. After a few brief moments, the blood pressure in your brain is restored to normal and the feeling of lightheadedness fades.
Regular aerobic exercise can lower blood pressure, decrease weight, and keep blood vessels more flexible. The American College of Sports Medicine and the Centers for Disease Control and Prevention recommend that people engage in moderate to intense aerobic activity four or more times per week for at least thirty minutes at a time. Walking, jogging, cycling, swimming, and climbing stairs are just a few examples of aerobic activity that force the large muscles of the body to use oxygen more efficiently.
Maintaining a healthy weight can reduce blood pressure and lower a person's cholesterol level. Eating a healthy diet and exercising regularly are the principal factors in maintaining a proper body weight.
Smoking is the worst thing a person can do to their heart and lungs. It increases heart rate, constricts major arteries, raises blood pressure, contributes to the development of plaque, and can create irregular heartbeats. A person who smokes can help reverse the negative effects caused by smoking merely by quitting. Within five to ten years, that person will face the same risks of heart disease as a nonsmoker.
People who like to drink alcohol should do so in moderation. The American Heart Association defines moderate alcohol consumption as no more than one ounce of alcohol per day. This roughly equals one cocktail, one 8-ounce glass of wine, or two 12-ounce glasses of beer. Excessive drinking raises blood pressure, can cause abnormal heart rhythms, and can even poison the heart, leading to death. Cocaine, heroin, and all other illegal drugs can seriously damage the heart and should be avoided completely.
Studies have shown that stress can increase heart rate and raise blood pressure. Chronic (long-term) stress can cause plaque to develop in the arteries, increasing the risk of atherosclerosis, heart attacks, and strokes. Exercising, getting enough sleep, practicing relaxation techniques, and thinking positively are a few methods to help reduce stress and keep the cardiovascular system healthy.