Americans have taken big steps to be healthier – like decreasing smoking and lowering blood pressure and cholesterol levels – but we still aren’t exercising enough and eating right.

Those conclusions from a recent American Heart Association (AHA) report highlight a serious statistic: in spite of some improvements, cardiovascular disease still kills one American every 40 seconds.

The report identifies two big factors that stand in the way of improving U.S. heart health: poor eating habits and a lack of physical activity.

"It always comes down to the same things: diet and exercise. It's a big, constant slap in the face that we're just not doing well as a country, and we're passing this on to our children," said Dr. Suzanne Steinbaum, AHA spokesperson and preventive cardiologist at Lenox Hill Hospital in New York City.

The report was published in the first January 2013 issue of the journal Circulation.

If those two current unhealthy trends continue, the AHA will miss its goal of reducing heart disease and stroke deaths by 20 percent by 2020 – by 13 percent.

"It is discouraging that we're not going to be meeting those goals," said Dr. Kenneth Ong, acting chief in the division of cardiology at the Brooklyn Hospital Center in New York City.

A 69 percent overweight rate

Almost a third of U.S. adults get no aerobic activity each week. That habit begins early, according to the data: during teen years 18 percent of girls and 10 percent of boys are getting less than an hour of aerobic activity each week.

Those sedentary lifestyles are contributing to a 35 percent obesity rate and a whopping 69 percent overweight rate among the population as a whole.

And although smoking has declined, the researchers found that 21 percent of adult men, 17 percent of adult women and 18 percent of high school kids smoke.

"Somewhere along the line, we lost our understanding of what it means to be healthy," Steinbaum said. "These findings are reflective of the life we're living, of [eating] fast, processed cheap foods."

But, Steinbaum said she’s seen patients make substantial changes. "I've seen people take ownership of their issues and change once they realize that if they can take care of themselves, they don't have to be sick. Now we need to figure out how to personalize public health initiatives," she said.

Start small to make big changes

The AHA report recommends working with health care systems to reward providers who help their patients improve their behaviors and their health. It also suggests working with educators to support healthy diets and exercise for children. Employers and insurers can offer wellness programs and cover preventive services. In communities, the AHA recommends ensuring green spaces are available for physical activity, and that there is access to healthy foods.

Both Steinbaum and Ong suggested starting with small steps. "Just go out for a walk. It's a simple thing that can make a difference. If you can't get out for a walk, even standing instead of sitting is better for you," Ong said.

Steinbaum's recommendation: "Do one little thing [each day] to make your lives healthier for a month. By the end of the month, you have 30 new healthy things. Instead of a Danish one day, have oatmeal," she said. "The next day, park your car a little further away. Make tiny changes. If you think about having to lose 60 pounds, it can be overwhelming, but you can do tiny things."

SOURCES: Suzanne Steinbaum, M.D., preventive cardiologist, Lenox Hill Hospital, New York City, and spokesperson, American Heart Association; Kenneth Ong, M.D., acting director, division of cardiology, Brooklyn Hospital Center, New York City; Jan. 1/8, 2013, Circulation