New dietary guidelines offer little new guidance

There isn’t much new in the latest iteration of the Dietary Guidelines for Americans. Three years in the making, the 2010 guidelines (released a tad late, on January 31, 2011) offer the usual advice about eating less of the bad stuff (salt; saturated fat, trans fats, and cholesterol; and refined grains) and more of the good stuff (fruits and vegetables; whole grains; seafood, beans, and other lean protein; and unsaturated fats). I’ve listed the 23 main recommendations below. You can also find them on the Dietary Guidelines Web site.

The guidelines do break some new ground. They state loudly and clearly that overweight and obesity are a leading nutrition problem in the United States, and that a healthy diet can help people achieve a healthy weight. They also ratchet down sodium intake to 1,500 milligrams per day (about two-thirds of a teaspoon of salt) for African Americans and people with high blood pressure or risk factors for it, such as kidney disease or diabetes. But the guidelines also leave the recommendation for sodium at 2,300 milligrams a day for everyone else, a move that the American Heart Association and others call “a step backward.”

Vague language spoils the message

One big problem with the guidelines is that they continue to use the same nebulous language that has made previous versions poor road maps for the average person wanting to adopt a healthier diet.

Here’s an example: the new guidelines urge Americans to eat less “solid fat.” What, exactly, does that mean—stop spooning up lard or Crisco? No. Solid fat is a catchphrase for red meat, butter, cheese, ice cream, and other full-fat dairy foods. But the guidelines can’t say that, since they are partly created by the U.S. Department of Agriculture, the agency charged with promoting the products of American farmers and ranchers, which includes red meat and dairy products. “Added sugars” is another circumlocution, a stand-in for sugar-sweetened sodas, many breakfast cereals, and other foods that provide huge doses of sugar and few, or no, nutrients.

Cautious thumbs up

Several Harvard-affiliated nutrition experts approved of the new guidelines with some reservations.

Dr. Walter Willett, chairman of the department of nutrition at Harvard School of Public Health, called the guidelines an incremental step in the right direction. “But they don’t give Americans the concrete steps they need to make healthy choices about food,” he cautioned. (You can read more on the guidelines from Dr. Willett and his colleagues at The Nutrition Source.)

Dr. David Ludwig, a nutrition and child obesity expert at Harvard-affiliated Children’s Hospital Boston, praised the new guidelines for emphasizing food choices and dietary patterns—rather than focusing on isolated nutrients—and for promoting a healthful ratio of fats, carbohydrates, and protein in the diet. He did have some quibbles with the 35% upper limit on fat in the diet and the guidelines assertion that the glycemic index of food—essentially, the effect food has on blood sugar levels—isn’t useful for managing weight.

Dr. George L. Blackburn, a nutrition and obesity expert at Harvard-affiliated Beth Israel Deaconess Medical Center, complimented the USDA and the Department of Health and Human Services for providing evidence-based dietary recommendations that focus on obesity.

Kathy McManus, a registered dietitian who directs the department of nutrition at Harvard-affiliated Brigham and Women’s Hospital, said the specific recommendations for sodium reduction are important. “This will be a challenge,” she said, “but we need to begin getting out the message and working with the food industry to support decreasing the amount of sodium in products.”

Bottom line

These experts are right in pointing to the positives of the 2010 Dietary Guidelines for Americans, which are supposed to help us decide what we should—and shouldn’t—eat. The new recommendations also provide evidence-based nutritional guidance for federal food programs like school lunches and food assistance. To truly help Americans choose healthier diets, though, the guidelines need to use plain language and offer unambiguous direction. Maybe they’ll get it right in the next update five years from now.

In the meantime, you can get straight talk on diet and nutrition from Healthy Eating: A guide to the new nutrition, a special health report from Harvard Health Publishing.

Recommendations included in the Dietary Guidelines for Americans

The guidelines divide 23 recommendations into four categories:

1) Balancing calories to manage weight

• Prevent and/or reduce overweight and obesity through improved eating and physical activity behaviors.
• Control total calorie intake to manage body weight. For people who are overweight or obese, this will mean consuming fewer calories from foods and beverages.
• Increase physical activity and reduce time spent in sedentary behaviors.
• Maintain appropriate calorie balance during each stage of life—childhood, adolescence, adulthood, pregnancy and breastfeeding, and older age.

2) Foods and food components to reduce

• Reduce daily sodium intake to less than 2,300 milligrams (mg) and further reduce intake to 1,500 mg among persons who are 51 and older and those of any age who are African American or have hypertension, diabetes, or chronic kidney disease. The 1,500 mg recommendation applies to about half of the U.S. population, including children, and the majority of adults.
• Consume less than 10 percent of calories from saturated fatty acids by replacing them with monounsaturated and polyunsaturated fatty acids.
• Consume less than 300 mg per day of dietary cholesterol.
• Keep trans fatty acid consumption as low as possible by limiting foods that contain synthetic sources of trans fats, such as partially hydrogenated oils, and by limiting other solid fats.
• Reduce the intake of calories from solid fats and added sugars.
• Limit the consumption of foods that contain refined grains, especially refined grain foods that contain solid fats, added sugars, and sodium.
• If alcohol is consumed, it should be consumed in moderation—up to one drink per day for women and two drinks per day for men—and only by adults of legal drinking age.

3) Foods and nutrients to increase

• Individuals should meet the following recommendations as part of a healthy eating pattern while staying within their calorie needs.
• Increase vegetable and fruit intake.
• Eat a variety of vegetables, especially dark-green and red and orange vegetables and beans and peas.
• Consume at least half of all grains as whole grains. Increase whole-grain intake by replacing refined grains with whole grains.
• Increase intake of fat-free or low-fat milk and milk products, such as milk, yogurt, cheese, or fortified soy beverages.
• Choose a variety of protein foods, which include seafood, lean meat and poultry, eggs, beans and peas, soy products, and unsalted nuts and seeds.
• Increase the amount and variety of seafood consumed by choosing seafood in place of some meat and poultry.
• Replace protein foods that are higher in solid fats with choices that are lower in solid fats and calories and/or are sources of oils.
• Use oils to replace solid fats where possible.
• Choose foods that provide more potassium, dietary fiber, calcium, and vitamin D, which are nutrients of concern in American diets. These foods include vegetables, fruits, whole grains, and milk and milk products.

4) Building healthy eating patterns

• Select an eating pattern that meets nutrient needs over time at an appropriate calorie level.
• Account for all foods and beverages consumed and assess how they fit within a total healthy eating pattern.
• Follow food safety recommendations when preparing and eating foods to reduce the risk of foodborne illnesses.