A Closer Look: The new guidelines for heart health
If you want to improve the health and fitness of your heart and blood vessels, you can. Basic lifestyle changes involving diet, exercise and smoking can make a big difference. It also helps to keep an eye on some key numbers, including blood pressure, cholesterol, body mass index and blood glucose.
Last year, the American Heart Assn. winnowed all this advice into a checklist called Life’s Simple Seven. For each item on the list, the AHA set criteria that define ideal cardiovascular health. In a nationwide study of nearly 18,000 adults, those who adhered to at least five of the criteria had a 55% lower risk of death over five years than those who met none.
Nearly everyone can find something to improve in terms of his or her heart health, says Dr. Ralph Sacco, president of the AHA and chairman of neurology at the University of Miami.
“When you ask Americans if they are in good health, about 35% say yes,” Sacco says. But, according to the AHA study, “less than 1% meet all seven of our criteria.”
Here’s a closer look at the new guidelines for heart health.
Smoking: Don’t do it. This is at the top of the list because the AHA calls smoking “the most important preventable cause of premature death in the United States.” It increases the risk of coronary heart disease, in which the vessels that carry blood and oxygen to the heart are narrowed due to a buildup of plaque. Smoking also decreases levels of HDL, the so-called good cholesterol, and makes the blood more likely to form dangerous clots, among other problems.
To meet the AHA criteria, you should be a nonsmoker or have quit for at least one year.
Maintain a healthy weight: Weight also correlates with heart disease. Too much fat — especially around the waist — increases the risks of high blood pressure, high cholesterol and diabetes.
Body mass index is a measure of weight relative to height. Though it’s an imperfect measure of a healthy weight, it does a good job of correlating with body fat. To calculate BMI, multiply your weight (in pounds) by 703, and divide that number by the square of your height (in inches). The AHA recommends a BMI below 25.
Exercise: Not only will physical activity help in the weight category, it also reduces blood pressure, increases HDL and improves the body’s sensitivity to insulin, which helps control blood sugar.
The AHA guidelines say to exercise moderately for at least 150 minutes per week or exercise vigorously for at least 75 minutes per week.
Healthy eating: The guidelines advise eating at least 41/2 cups of fruits and vegetables per day, at least 3 ounces of whole grains per day, at least two servings of fish each week, less than 1,500 milligrams of sodium per day and no more than 450 calories worth of sugar-sweetened beverages in a week. To meet the heart-healthy ideal, you should follow at least four of these five rules.
Studies have shown that diets high in fruits and vegetables can reduce high blood pressure and other risk factors for heart disease. It’s not clear whether the foods themselves make that happen or whether people who eat lots of fruits and vegetables also eat fewer unhealthful foods.
There’s also evidence that whole grains reduce LDL, the bad cholesterol, even for people on low-fat, low-cholesterol diets. Fiber slows the progression of cardiovascular disease in high-risk patients.
Eating fish is better than using fish oil supplements, Sacco says, because the data on supplements has been “disappointing” — with some studies finding a benefit and many others not. No recommendations are made for other kinds of supplements — such as antioxidants, vitamin E and beta-carotene — due to mixed results in the scientific literature. Of course, doctors still may recommend supplements for individual patients, Sacco says.
The sodium goal is lower than in previous guidelines, but new data support the 1,500 mg daily limit. An AHA Presidential Advisory published last month in the journal Circulation summarizes dozens of clinical trials showing that reducing sodium intake to that level lowers systolic blood pressure (the top number) by an average of 2 points in people with normal blood pressure and by an average of 5 points in people with high blood pressure.
Watch your numbers: There are three important physiologic measures that increase the risk of heart disease if they rise above the normal range: blood pressure, blood cholesterol levels and blood glucose.
The AHA guidelines say that blood pressure should be maintained below 120/80 millimeters of mercury, total cholesterol should be below 200 milligrams per deciliter of blood and fasting blood glucose should be below 100 mg/dL of blood.
“Every American should know these numbers,” Sacco says.
Studies show that people who keep all three factors in the healthy range reduced their risk of death from cardiovascular disease over 16 to 22 years by 70% to 85% compared with people with at least one measure in a high-risk range.
Some doctors argue that a measure of inflammation called C-reactive protein should join this list of numbers to know, as is the case in Canada. There is some evidence from clinical trials that lowering C-reactive protein protects against cardiovascular disease, says Dr. Paul Ridker, director of the Center for Cardiovascular Disease Prevention at Brigham and Women’s Hospital in Boston.
