Uncle Sam wants you to eat your veggies

Uncle Sam has some new diet and fitness advice for Americans, and it's not what most of us want to hear. Think you get enough exercise, eat a good variety of healthy foods, and keep dietary splurging to a minimum? Think again.

The 2005 version of the Dietary Guidelines for Americans, updated every five years, places a new emphasis on controlling weight through regular exercise and diet, and its recommendations may come as a shock to those of us who thought we were doing pretty well. For example, while previous government recommendations prescribed 30 minutes of moderate physical activity five days a week, the new Guidelines recommend 60 minutes of moderate physical activity on most days to prevent weight gain-and up to 90 minutes a day if you're trying to lose weight.

The new dietary advice is equally rigorous. It starts with computing the daily calories needed for your age, sex, height, weight, and activity level. Once you've obtained an individualized dietary plan based on your specific energy needs, you'll need to measure portion sizes, keep track of consumption within various food groups, and count total calories. For example, if you require 2,000 calories a day to maintain your current weight, the Guidelines call for your daily food intake to include:

• four servings (2 cups) of fruit,
• five servings (2.5 cups) of vegetables,
• three cups of skim milk or the equivalent,
• six ounces of grains (at least half of them whole grains),
• five and a half ounces of lean meat, fish, or beans, and
• no more than six teaspoons of healthy oils.

If it sounds like there won't much left in your calorie budget for extras, you're right. After eating the nutrient-dense foods you need from each food group, the Guidelines estimate you'll be left with approximately 265 of your 2,000-calorie-a-day allotment. You can spend these "discretionary calories" on additional servings in any food group, on "luxury versions" of the foods in each group (like higher-fat meat or dairy products or sweetened cereal), or on extras, such as sweets, higher-fat dressings or sauces, soda, or alcoholic beverages.

How much are you really eating?

MIT Medical nutritionist Anna Jasonides, R.D., applauds the Guidelines' new emphasis on exercise-finding the right balance between calories in and calories out-as well as the limits on total daily calories and servings and the specificity regarding portion size. "The old pyramid left a lot open to interpretation," she notes. "For example, it called for six to 11 servings of grains a day. But it wasn't clear what constituted a serving or which grains were healthiest. Many people felt they had a green light to eat all the grains they wanted, and they ended up consuming too many calories and gaining weight."

In contrast, Jasonides continues, the new pyramid provides limits. "If you're eating 2,000 calories a day, your individualized pyramid plan limits you to six servings of grains per day-that's six one-ounce servings!" But, says Jasonides, she still expects people to have difficulty translating those one-ounce serving recommendations to real-life portions. "People need to look at how the guidelines define a 'one-ounce equivalent' of grains or a 'half-cup equivalent' of fruits or vegetables, and then they need to look at how much they are really consuming."

Calories count!

What Jasonides hopes these new Guidelines won't do, she says, is cause people to "pit one food against the other." Citing cultural differences and the variety of diets that manage to produce healthy outcomes, Jasonides asserts, "There's no one way to eat. Different types of diets can all work," she continues, "as long as the total calories are low enough and you're getting enough exercise. If people eat a good variety of foods from different basic groups, keep the portions small, and limit the truly empty calories, I don't think they really have to worry about the fat in cheese."

Portion control is key, Jasonides stresses. "I talk to so many people who tell me they shop at Whole Foods and make 'healthy food choices,' and they just can't figure out why they're overweight," Jasonides says. "Well, it turns out that their 'healthy dinner' is a 12-ounce piece of swordfish, a giant baked potato, a huge bowl of salad with a lot of healthy dressing, and two whole ears of corn. It's all 'good food,' but it's just too many calories. Calories count!"

 

For more information on the Dietary Guidelines for Americans, 2005, read related articles in this issue of health@mit and visit the official MyPyramid website at http://www.mypyramid.gov.