There are hopeful signs that Americans are increasingly embracing a heart-healthy lifestyle. The percentage of smokers has plunged to approximately 15% over the last decade. Many people are eating better and doing a better job of controlling high blood pressure and elevated cholesterol.

But despite these gains, cardiovascular disease still accounts for one out of three deaths in the US. Much of the blame goes to the obvious culprits that fuel heart disease—cigarette smoking, elevated blood cholesterol, high blood pressure, obesity, diabetes and a lack of exercise, to name a few. But others might surprise you.

SMALL CHANGES COUNT

Research shows that our daily habits account for 40% to 50% of all deaths caused by cardiovascular disease. The good news is that even small lifestyle choices may offer big benefits. Five little things you can do to reduce heart attack risk… 

Secret #1: Avoid secondhand smoke. Most people associate secondhand smoke with lung disease—but the danger to the heart is worse than you may realize.

Here’s why: Exposure to cigarette smoke—from smoking yourself or from secondhand smoke—increases arterial inflammation and impairs the ability of arteries to dilate and constrict normally. It also makes blood more likely to coagulate, the major cause of heart attacks.

If you live with an indoor smoker or spend time in other smoke-filled environments, your risk for a heart attack is 30% higher than in someone without this exposure. Cities (and countries) that have adopted public-smoking bans have reported reductions in heart attacks of 20% to 40%—with most of the reductions occurring in nonsmokers.

Secret #2: Know your family genes. If you have inherited gene variants known to increase the risk for heart disease, your risk of developing coronary disease and having a cardiac event is higher than you probably think. In an important new study, researchers from Massachusetts General Hospital followed more than 55,000 participants for up to 20 years, analyzing genetic variants and lifestyle data. Conclusion: People with a genetic predisposition for heart disease had nearly double the risk of developing it themselves.

But bad genes don’t have to be destiny. The same study found that people who made positive changes in two or three out of four common areas known to negatively impact heart health—smoking, obesity, lack of regular exercise and an unhealthful diet—were able to reduce their cardiovascular risks by nearly 50%.

Secret #3: Get a flu shot. The flu can be deadly, yet fewer than half of at-risk Americans (including those with chronic health conditions, such as cardiovascular and/or lung disease) get an annual vaccination.

Why it matters: The fever, dehydration and pneumonia that often accompany the flu can be devastating for people who have cardiovascular disease. The flu can worsen preexisting conditions such as heart failure or diabetes or trigger an asthma attack or heart attack in some people.

A 2013 JAMA study that looked at more than 6,700 patients (mean age, 67 years) found that those who got a flu vaccination were 36% less likely to suffer cardiovascular events (such as heart attacks) during the following year than those who weren’t vaccinated. When researchers looked only at patients who had recent cardiac events, they found that vaccination cut the risk by 55%.

Recommended: An annual flu shot for everyone age 50 or older…and for anyone who has been diagnosed with cardiovascular disease. Adults age 65 and older should discuss the pros and cons of the high-dose flu vaccine with their physicians—it’s reported to be about 24% more effective than standard vaccines but may have greater side effects.

Secret #4: Don’t stop taking a beta-blocker drug abruptly. Used for treating high blood pressure, irregular heartbeats, rapid heart rates and many other conditions, beta-blockers are among the most commonly prescribed drugs in the US.

Drugs in this class—propranolol (such as Inderal), atenolol (Tenormin) and many others—are generally safe but may cause side effects including fatigue, light-headedness and even impotence. As a result, patients sometimes decide on their own to stop taking these drugs.

The danger: If these drugs are suddenly stopped, the patient can have a dangerous upsurge in adrenaline activity, which can cause a faster heart rate, heavy sweating, spikes in blood pressure and an increased risk for heart attack and stroke. People who want to stop taking a beta-blocker are advised to slowly decrease the dose over 10 to 14 days.

Important: If you believe that you need to stop taking any prescribed medication, be sure to first check with your doctor. If side effects are a problem, you can probably switch to another drug or a dose that’s easier to tolerate.

Secret #5: Lower your resting pulse. When you increase your heart rate during aerobic exercise, you’re helping to prevent a heart attack or stroke—this signifies that you’re getting the cardiovascular benefits of moderate-to-vigorous exercise. Paradoxically, a slower resting heart rate is also protective.

Here’s why: In general, a slower resting rate means a longer life—probably because a slower heart rate exerts less stress on blood vessel walls. Studies have shown that healthy men and women with lower resting heart rates (less than 60 beats per minute) have fewer cardiac events and a lower risk of dying from cardiovascular disease than those with faster rates (greater than 80 beats per minute).

A study of heart patients taking beta-blockers found that each 10-beat reduction in resting heart rate reduced the risk for cardiac death by 30%. For example, if someone with a resting heart rate of 80 beats per minute is given a beta-blocker to slow the rate to 60, the risk for cardiac death will drop by 60%.

Recommended: A resting heart rate of 50 to 70, depending on your cardiac history and typical physical activity level. Regular exercise…quitting smoking…maintaining a healthy weight…and avoiding high doses of caffeine can slow the resting heart rate.

Also important: Your recovery heart rate, the time that it takes your pulse to approach its resting rate after exercise. The fitter you get, the more quickly your heartbeat will return to a resting rate.