Low-calorie, low-fat, low-carb, slow foods: What's left?

How about a high-protein, low-fat, moderate-carb diet — exactly what works, according to research. Protein makes you feel full longer than carbs and fat do. And, according to a recent study in the American Journal of Clinical Nutrition, you don't even have to eat low-carb to get results.

According to lead study author Dr. D. Scott Weigle, a professor of medicine at the University of Washington School of Medicine, "If you compare different diets, all with the same percentage of carbohydrates, the satiety was significantly higher when daily intake was almost one-third protein."

In the study, the participants lost weight on a diet of 30 percent protein, 50 percent carbs and 20 percent fat. One segment of the study group was able to eat whatever they wanted as long as they maintained the 30 percent protein intake. They spontaneously dropped their average daily intake by 450 calories, resulting in an average weight loss of 11 pounds over 12 weeks.

Many studies are now reporting the positive effects of protein on weight loss. In a recent review in the Journal of the American College of Nutrition, Dr. Frank Hu, a professor of nutrition and epidemiology at Harvard University's School of Public Health, confirmed protein's weight-loss power.

Why protein works

First of all, high-protein foods slow the movement of food through the gastrointestinal tract, and slower stomach emptying means you feel full longer and get hungry later. "The evidence also suggests high-protein meals lead to a reduced subsequent calorie intake," says Hu.

Protein also helps keep blood sugar stable, avoiding the quick rises that can occur when you eat carbohydrates. Also, eating foods that are low-fat, low-carb and high in protein will help you avoid other less-healthy, high-calorie foods.

Lastly, the body uses more calories to digest protein than to burn fat or carbohydrates. Hu believes you could burn 30 more calories per day simply by eating a diet of about 30 percent protein.

The diet

The idea is to eat small to moderate amounts of healthy fats (for example, vegetable oils, nuts and avocados), a moderate amount of "good" carbs (fruits, vegetables and high-fiber whole grains) and a moderate amount of low-fat protein (fish, egg whites, skinless chicken and turkey breast, beans, low-fat dairy products). The breakdown should be 25 to 30 percent protein, 45 to 50 percent carbs and about 20 percent fat.

Safety

There are some potential health problems associated with increased protein consumption, such as the depletion of calcium. However, the Institute of Medicine (IOM) has concluded that there is no clear evidence that high protein intake increases the risk of kidney stones, osteoporosis, cancer or cardiovascular disease. Currently, the IOM recommends that 10 to 35 percent of calories in an adult's diet may come from protein. That protein includes the following:

Poultry

The leanest is white meat from the breast of chicken or turkey without skin. Other tips: Remove the skin to cut the fat by almost half. Trim all fat before cooking. Instead of butter or oil, try flavored vinegars, wines, herbs, spices or citrus fruit. Bake, roast, broil, grill, poach or stir-fry using cooking spray.

Fish

Fish is a great source of protein and heart-healthy omega-3 fatty acids. Worried about mercury? Check out the FDA Web site www.cfsan.fda.gov/~frf/seamehg.html) for information.

Meats

These include beef, veal, pork and lamb. As long as it's lean and you control portion size and frequency, you can still have meat.

The leanest beef cuts include round steaks and roasts (eye round, top round, bottom round, round tip), top loin, top sirloin and chuck shoulder and arm roasts.

The leanest pork choices include pork loin, tenderloin, center loin and ham.

Choose extra-lean ground beef. Choose lean roast beef, ham or low-fat meats for sandwiches instead of those with more fat, such as regular bologna or salami.

Avoid meat that is heavily marbled.

When cooking

Trim visible fat beforehand. Broil, grill, roast, poach or boil meat instead of frying.

Drain any fat that appears during cooking.

Dairy

Dairy is a great source of protein and calcium, and especially important to replace potential lost calcium from eating higher amounts of protein. However, it is full of fat, so always choose low-fat or nonfat milk, yogurt and cheese.

Egg whites

Egg whites are virtually fat-free.

Other protein sources

Nuts, seeds, beans and legumes are super-healthy, but nuts and seeds are very high in fat, (although it's good fat), so make sure to limit portion sizes. Prepare beans and legumes without added fats.

Charles Stuart Platkin is a nutrition and public-health advocate. Copyright 2005 by Charles Stuart Platkin. Write to info@thedietdetective.com.