It's no secret it can be challenging to maintain resolutions about eating healthy and staying fit. And now is when good intentions – especially those that began oh-so-long-ago at the beginning of the year – can start to wane.

But rather than relying on vague ideas about changing your behavior, setting realistic, attainable goals more often leads to success, research has shown.

To keep on track, choose simple, specific strategies and make gradual changes, said Linda Van Horn, chief of nutrition in the department of preventive medicine at Northwestern University Feinberg School of Medicine in Chicago.

Then, Van Horn suggests, build on those accomplishments to expand your healthy efforts.

Rather than, "I plan to lose 10 pounds by spring break," try, "I will eat an apple each day during that afternoon slump, rather than those chips" or "I will walk 15 minutes coming and leaving from work."

"Be successful all year," Van Horn said in advocating a slow-and-steady approach. The changes can lead you to a longer, more active and healthier life.

Pick one habit that's easy to achieve – literally the "low-hanging fruit" – such as adding one serving of a fruit or vegetable to your diet each day, Van Horn said. Fruits and vegetables contain vitamins, fiber and other nutrients that provide a variety of health benefits. It can become a daily habit, and one you soon may miss if you don't follow through.

Next, select another new behavior. For example, start reading nutrition labels on foods at the grocery store to find a low-sugar yogurt, a high-fiber cereal or a low-sodium soup.

"Reading labels is another habit that, once in place, you find yourself checking these facts whenever you are considering a new processed food," Van Horn said.

Other potential healthy changes: Designate a "vegetarian day" or "fish day" each week. Add more steps to your day to increase physical fitness. Try getting an extra hour or even half an hour of sleep. Each new behavior can contribute to your healthier lifestyle and add confidence in your ability to change for the better.

After adopting new habits to kick-start your resolutions, consider moving to another level with additional identifiable health goals – either later in the year, or even as another new year approaches.

"The next set of changes will get easier," Van Horn said.

Parents can expand family health goals by including children in the selection, preparation and cleanup of foods and meals, Van Horn said.

"Be the role model and then watch them hold you accountable for sticking with a healthy eating plan," she said. "They are never too young to start, and you have the greatest potential to shape their future eating behavior – as well your own."

Cooking at home gives you more control over the foods, ingredients and preparation, which can result in healthier eating, and it can keep your household budget in line by reducing restaurant bills.

If your cooking skills are lacking, look for a healthy cooking class at a community center, a specialty food or kitchen store or even online. "They are everywhere," Van Horn said.

Regular moderate exercise not only helps combat heart disease, stroke and other health problems, but it can keep your health care costs down.

One group of researchers examining surveys of more than 26,000 American adults found that the average health care costs for those who regularly exercised was more than $2,500 less than those who didn’t. Physical activity doesn't have to mean joining a gym. You can get outdoors and exercise for free at a local park or walking trail.

A separate study examined the effects of specific healthy behaviors on medical costs. For instance, quitting smoking can save $1,000 a year or more for pack-a-day smokers. So, consider taking advantage of a low-cost smoking cessation program offered through your health care plan.

Remember that keeping a watch on your blood pressure, blood sugar and cholesterol numbers contributes to your overall health and usually isn't expensive. Most of these screenings are part of preventive exams in health care plans.

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