Cereal box readers likely recognize the Food Guide Pyramid, a graphic designed by the US Department of Agriculture (USDA) as an easy-to-follow guide to healthy eating. The pyramid's designers thought that by featuring common foods, more people would make use of it in order to achieve a balanced diet.
But some researchers are not happy with the nutrition message conveyed by the USDA pyramid. They think the government's recommendations rely too heavily on animal foods and refined grains and that they give "heart-healthy" vegetable oils too little recognition.
Harvard University's Dr. Walter Willet is one critic who has gone a step further: He's devised his own pyramid that realigns the concept of a healthy diet. His version, outlined below, represents the most recent advances in nutrition and health research.
#1: Build your own base
Daily exercise and weight control are the foundations of Willett's pyramid. We now know that many chronic diseases such as diabetes, heart disease, obesity, and osteoporosis that plague Americans are a direct result of inactivity. The scientific consensus is that we should all center our days around being active in ways we enjoy - walking the dog, going for a bike ride, or going to the gym. It's not so much intense exercise as leisure activities that help maintain good health. The bottom line is that it won't matter how well we eat if we don't get moving.
#2: Hello fat, goodbye pasta!
Good fats and whole grains are next in line for better health. The bread, cereal, rice, and pasta that appear at the base of the original pyramid are all high in carbohydrates, the body's primary source of fuel. In addition, grain products are high in fiber, minerals, and other vitamins. But the USDA pyramid ignores the fact that the most common grain products on grocery store shelves - white bread, crackers, pasta, and cereal - are made with refined flour that has lost nutrients during processing. The pyramid fails to distinguish between a plateful of pasta and bowl of whole grain oats.
Some scientists think that a diet high in refined grain foods like white rice, potatoes, and products made from white flour may actually be fueling the increase in diabetes, heart disease, and obesity around the country. If so, then it's not the carbohydrates themselves that are responsible for any ill-health effects, but the form that they come in.
Tufts researcher Susan B. Roberts maintains that refined carbohydrates cause a rapid rise in blood insulin - a hormone that keeps blood sugar levels in control. Many researchers believe that consuming too much of these foods overtaxes our system and makes us more prone to diabetes and heart disease. Whole grain foods such as whole wheat, brown rice, or oatmeal, on the other hand, are good sources of fiber, which slows the release of carbohydrates into the bloodstream and stops insulin levels from spiking. Keeping insulin on an even keel, say the scientists, is key to weight control. Whole grains also contain a slew of phytochemicals that experts believe help to maintain good health.
And, believe it or not, Willet says that fat belongs at the very bottom of the pyramid, right next to whole grains. The USDA Pyramid places fat at the top, to be consumed in very limited quantities, but not all fats are the same. Saturated fats - from meat and dairy foods - can contribute to the development of heart disease. But vegetable oils such as olive and canola may well deserve a prominent place in the American diet. These mono- and polyunsaturated fats are considered "heart-healthy" because they do not raise blood cholesterol levels and may even help slow the progression of heart disease. This notion of good versus bad fats is supported by the fact that Mediterranean cultures which consume a high amount of plant oils and fatty fish have very little incidence of diabetes and heart disease.
#3: Vitamins, minerals, fiber, and phytochemicals
Once our basic energy needs have been met, the class of foods to focus on is the plant kingdom. Vegetables and fruits in abundance will provide essential vitamins and minerals and enough fiber and disease-fighting phytochemicals to help keep you healthy. Although five servings a day is the standard recommendation, no one will dispute that the more you get, the better. In fact, Tufts scientist Jim Joseph recommends up to nine servings a day to reduce the risk of cancer and other age-related diseases. To get the most from your servings, choose leafy greens, lots of berries, and shoot for maximum color diversity. Every color of fruit or vegetable delivers unique health benefits.
#4: Peanuts?
Yes, that's right, nuts. Not only do nuts provide high-quality protein, they also come packed with 'good' fats, or fats that help lower 'bad' cholesterol. Beans are another good source of protein, with the added value of fiber, which helps to control appetite. Beans may help reduce the risk of heart disease, and may even fight cancer.
#5: Fish, poultry, and eggs
The USDA Pyramid puts nuts, legumes, red meat, fish, and eggs all in one category. While this suggests these are all equal, research shows they are indeed very different. Unlike red meat, fish has almost no artery-clogging saturated fat. Instead, it has lots of 'essential fats,' the kind that help produce important hormones that regulate body functions and may help prevent heart attacks. Eggs are also getting another look as a good source of protein - new research shows that an egg a day is not bad for your heart and egg yolks contain phytochemicals lutein and zeanxanthin that help fight age-related cataracts.
#6: Dairy
A growing school of thought in the nutrition community believes that it's not necessary to rely solely on dairy foods for calcium, and points to evidence that many Americans' diets lack the minerals needed for calcium balance. According to research by Tufts nutrition expert Katherine Tucker, if we focused more on whole foods, such as whole grains, legumes, and produce, we would create a positive mineral balance and easily meet our daily calcium needs. Not all plant foods contain calcium, though, so try some good alternative sources of calcium, such as soy-based products and calcium-fortified orange juice before you ditch dairy from your diet.
Use sparingly
Willett's revised pyramid lumps red meat, butter, white rice, white bread, potatoes, pasta, and sweets into one category at the very tip of the pyramid, all to be consumed sparsely. Red meat and butter contain a lot of harmful saturated fat, while potatoes, refined grain products, and sweets contain 'empty calories' that may contribute to weight gain and diabetes.
Not all scientists buy into the theory that potatoes and pasta are bad for you, but most agree that loading up on one kind of food (like pasta) while shunning others (like vegetables) is an unhealthy way to eat. Regardless of how researchers package it, though, most nutrition advice is basically the same: eat a diet high in fruits, vegetables, and whole grain foods, eat less red meat and more fish, choose low-fat dairy foods if you include dairy in your diet, and go with vegetable oils and spreads over animal fats like butter.
