Studying the diets of 7,500 Americans, scientists found that people eating a low-calorie-dense diet (plenty of fruits, vegetables, and fiber-rich grains) ended up eating a lot more food over the course of the day but a lot fewer calories than people eating calorie-dense fare like fatty meats, cheese, and sugar-rich, white-flour-rich foods.
As you learned in nutrition class at the Pritikin Longevity Center, this is “the calorie density solution.” And this is just one more study that demonstrates the beneficial effects of a low-calorie-dense diet.
Foods with a low calorie density, like nonstarchy vegetables, have relatively few calories pound for pound (65 to 195) compared to foods like chocolate bars or cookies that pack in more than 2,200 calories per pound.
The researchers found that compared with high-calorie-dense eaters, low-calorie-dense dieters took in several hundred fewer calories each day – an average of 425 fewer among men and 250 fewer among women.
Yet, the low-calorie-dense-eaters ate more food and more nutrients – more calcium, more iron, more potassium, and more vitamins A, C, B-6, and folate – than those eating fattier, richer, calorie-packed foods, reported the authors, lead by Dr. Jenny Ledikwe of Pennsylvania State University.
In an accompanying editorial entitled “Energy Density: What a Concept,” Dr. Linda Van Horn, one of the nation’s leading nutrition experts, applauded Dr. Ledikwe’s new study, noting that it “conveys the benefits of a low-energy [calorie]-density diet rich in complex carbohydrates and satiety compared to a high-energy diet.”
Go Veggie, Go Lean
For a leaner, healthier weight, skip the meat and focus on plant-based, fiber-rich foods, such as vegetables, fruits, whole grain cereals, and beans, concluded more recently published research on more than 55,000 healthy, middle-aged Swedish women.*
Studying dietary questionnaires the women completed over a ten year period, scientists found that “omnivorous women [those who ate meat and/or poultry every day] were significantly heavier than any of the three vegetarian groups,” stated lead author PK Newby, MD, from the USDA Human Nutrition Research Center at Tufts University in Boston.
The three vegetarian groups included vegans (no meat, fish, eggs, or dairy products), semi-vegetarians (some fish, eggs, and dairy products), and lactovegetarians (some dairy products).
More Meat, More Obesity
The prevalence of overweight or obesity (a Body Mass Index, or BMI, greater than 25) was 40% among the omnivores, 29% among both vegans and semi-vegetarians, and 25% among lactovegetarians.
The meat-eaters took in the most calories, the highest amounts of protein and fat (about 30% of daily calories as fat), and far fewer carbohydrates compared to the three vegetarian-based groups. And the type of carbohydrates the meat-eaters consumed was problematic, noted Dr. Newby and colleagues. “The omnivores had the highest intake of refined grains.”
By contrast, all three vegetarian groups had higher intakes of fruit, vegetables, whole grains, and fiber. They ate at least two servings daily of whole grains, three of vegetables, two of fruit, and one of starchy vegetables like potatoes.
These results, wrote USDA researcher Newby, “suggest that a high-carbohydrate diet may be protective against obesity if the carbohydrates come from fiber-rich foods such as fruit, vegetables, and whole grains.”
Agrees Jeffrey Novick, MS, RD, LD, LN, Director of Nutrition at the Pritikin Longevity Center® & Spa in Aventura, Florida, "If I were to write a nutrition book, the first and MOST IMPORTANT chapter would be entitled ‘FIBER.’ The more naturally-rich-in-fiber foods you eat, the greater your chances of not only shedding excess pounds but also living long and well."
* Journal of the American Dietetic Association, 2006; 106: 1172.
** Journal of the American Dietetic Association, 2006; 106; 1153.
American Journal of Clinical Nutrition, 2005; 81: 1267.