We've all heard the message: Eat right, exercise more. Whether it's new federal nutrition guidelines or today's Great American Weigh-In, public health officials are urging Americans to do more to keep their weight under control as a way to lower the risk of cancer and other chronic diseases.

But how is the average person supposed to follow all this advice? We asked our in-house expert, ACS director of nutrition and physical activity Colleen Doyle, RD, to help one American Cancer Society employee move closer to those goals. Here is her assessment:

Gregg is 44 years old and the father of two. He works full time and has a house in the suburbs. He also has a family history of heart disease and cancer -- which has motivated him to do all he can do to live a healthier life so that his two young sons, Chayce and Jaydn, will have their father around for a long, long time.

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Gregg would tell you that, like for so many of us, family and work responsibilities frequently work against him in achieving his health goals. He wants to exercise more. He wants to eat better. He wants to lose about 40 pounds. But he works long hours and has a long commute every day (about 2 hours round trip). And with two kids under the age of 5, plans to eat well and exercise sometimes take a back seat to just getting through the day.

Gregg recognizes that he's got to really make a commitment to improving his health. With everything else he has to accomplish during the day, if he doesn't make himself a priority, as the old saying goes…it ain't gonna happen. So, we sat down and talked about his current physical activity and exercise habits, and how he can make some small changes that will add up to big-time benefits.

Gregg has recently made a fabulous lifestyle change that helps him get in the physical activity he needs: He started getting up earlier in the morning and working out before he gets to the office. He now leaves his house at 5:30 in the morning to make it to the gym by 6:00. Not only is he more likely to stay with this routine (he gets his work-out in before other priorities start crowding the day), his commute time is better since he doesn't fight as much traffic earlier in the morning.

Gregg's neighborhood also has close and easy access to a park -- a great place to get out and be active as a family.

Gregg should be shooting for 60-90 minutes of activity each day. His morning workout is typically an hour, so looking for other opportunities to add activity throughout the day will be helpful. Taking the stairs instead of the elevator, parking his car farther away in the parking deck, and playing with his boys can all help those minutes add up.

Like a trooper, Gregg wrote down everything he ate and drank for a week. On weekdays, breakfast is usually a bowl of oatmeal, a banana, and a cup of low-fat yogurt. Lunch is often a sandwich, and dinner is usually some kind of meat with vegetables. Gregg likes to snack on fruit, but sometimes those little temptations we all face -- birthday cake or candy from our kids' holiday parties -- sneak into his diet, too.

While Gregg's overall goal is to make long-term lifestyle changes, and that includes losing weight. Based on what he currently weighs, Gregg consumes about 3,100 calories each day. People who lose weight slowly -- at a rate of 1-2 pounds per week -- are more likely to maintain that loss. To lose 2 pounds per week, Gregg will need to create a "calorie deficit" of 1,000 calories per day. It would be best for him to do this through a combination of fewer calories in and more calories out -- decreasing how much he eats, and increasing how much he exercises. As I looked over his food records and talked with him, a few areas emerged where I think he can make some good changes.

Keep eating breakfast: People who eat breakfast are less likely to overeat throughout the day. Gregg's breakfast is usually high carb, which is great for replenishing his muscle glycogen stores after his morning workout. Adding lower-fat protein sources -- Canadian bacon and fat-free yogurt instead of their regular versions, for example -- will help lower his saturated fat intake, keep hunger pangs away, and help maintain his blood sugar level.

Try smaller meals throughout the day: "Mini meals" throughout the day may help with weight control. Gregg sometimes has 2 sandwiches for lunch; dinner frequently includes 2-4 servings of grains. Spacing out those calories -- eating fewer calories more frequently throughout the day -- may help burn some extra calories. Whether or not Gregg becomes a "grazer," eating a smaller dinner is a good idea -- he's less likely to burn off calories eaten at night (although chasing two kids into the bathtub helps!).

Fruits and vegetables: Based on Gregg's calorie level, he should shoot for eating at least 2.5 cups of fruit each day and 4 cups of vegetables. He does a good job at eating a variety of each. He frequently snacks on fruit -- especially "easy to go" fruit that meshes with his fast-paced life: boxes of raisins, individual containers of cut-up fruit. To cut back on calories and still get the servings of fruit he needs, he should think about drinking less juice and eating the whole fruit, instead. Gregg tends to eat most of his vegetables at dinner. Meeting his recommended intake will mean adding more vegetables to lunch and snacks. Since he's a "sandwich guy" at lunch, adding colorful lettuce and tomatoes is a good start. On weekends, when he is more likely to have scrambled eggs for breakfast, adding peppers, mushrooms and onions can help boost his vegetable count.

Whole grains: Gregg needs to eat about 5 servings of whole grain foods each day. His breakfast usually includes oatmeal, so he's off to a good start. Looking for other places to add whole grains -- brown rice at dinner instead of white; whole wheat hamburger buns; snacking on a whole grain cereal or popcorn – will help him get there.

Healthy protein sources: Especially to reduce his intake of saturated fat, I'd like to see Gregg swap out red meat for more chicken, turkey, fish and other seafood. He eats beans in salads and soups -- another great way for him to get the protein he needs without the fat (and with fewer calories).

Calcium: Gregg is lactose intolerant, which means he can't eat a lot of dairy products. He is able, though, to eat small amounts of yogurt and cheese. Other sources of calcium include fortified cereals and orange juice, greens, and tofu. To get the calcium he needs, he could also consider taking a calcium supplement.

Sodium: Gregg watches his sodium intake because of a family history of high blood pressure. He chooses low sodium breakfast meats and watches how much salt he adds at the table. He does eat canned vegetables and soups on occasion, so he should be sure to read the label to find out just how much sodium he consumes. Most people should limit their sodium intake to 2,300 mg per day (that's about 1 tsp of salt). Because of Gregg's family history of high blood pressure, he should limit his intake to 1,500 mg per day.

Potassium: Gregg's family history of high blood pressure also means he needs to get enough potassium in his diet. He should aim to get at least 4,700 mg per day. The bananas and yogurt he eats are two good sources of potassium. Many fruits and vegetables are good sources of potassium, so increasing the amount of these foods will help him meet his needs.

Supplements: Gregg currently takes a variety of supplements, including ornithine and arginine, two amino acids that are often promoted to build muscle and increase fat loss among athletes. Gregg likely gets plenty of these amino acids already in the protein he consumes each day. He also takes two different "men's formula" multivitamins. Excessive intake of the fat soluble vitamins -- A, D, E and K -- can be harmful over time because they are stored in the body and can build to toxic levels. When your tissues have enough of the water soluble vitamins, you excrete them -- so Gregg likely has very expensive urine! If Gregg feels the need to take a supplement, he should read the label and select one that provides 100% of the Daily Value for vitamins and minerals; he does not need to be taking multiple supplements.

Sweet treats: Like many of us, Gregg likes his sweets. Even while trying to lose weight, he doesn't have to totally pass them up! Based on his food records, I can tell that Gregg uses good "portion control" sense when satisfying that sweet tooth: He'll limit himself to two cookies instead of four; he'll indulge in a bite-size candy bar. And what about those days when he just has to indulge in a co-worker's delicious cheesecake or the favorite deep-dish apple pie his wife makes for his birthday? Grab a fork, enjoy a little bit, and add in an extra workout or two!