REBUILDING THE FOOD PYRAMID (1-2003)

For more than a decade the official advice from the U.S. 
government on what people should be eating for proper 
nutrition has been to follow the United States Department 
of Agriculture’s Food Pyramid. Sometime this year, the USDA 
may decide it was wrong all along.

The food pyramid guide is a graphic representation of the 
nutrition recommendations of the USDA, with carbohydrates 
at the base, fiber-rich foods like fruits and vegetables in 
the middle, and high-protein and fatty foods near the apex.

But Dr. Walter Willett, an epidemiologist at Harvard 
University, believes the USDA’s food pyramid may be causing 
more nutritional problems than it is solving. So he set out 
to develop a better one. It is Willett’s revised pyramid, 
or one similar to it, that the USDA may make official 
within the next year or two.

The original pyramid was put into place without much 
scientific support. It is oversimplified to the point of 
being worthless at best and harmful at worst. 

Writing for a recent issue of “Scientific American,” 
Willett said, “Although the USDA's food pyramid has become 
an icon of nutrition over the past decade, until recently 
no studies had evaluated the health of individuals who 
followed its guidelines.”

So Willett and colleagues set out to discover if there 
really is a benefit to following the food pyramid. Using 
epidemiological studies, and allowing for variables such as 
smoking and exercise, the researchers concluded that 
following the dietary advice of the food pyramid does not 
improve overall health.

Although eating a lot of vegetables, as advised by the 
pyramid, may improve health, eating lots of refined 
carbohydrates – the pyramid’s base – is harmful. Studies 
show that eating too many refined carbohydrates increases 
the risk of diabetes and heart disease more than eating 
fat. So any benefits gotten from following the food 
pyramid’s recommendation to eat fiber-rich vegetables is 
offset by its recommendation to eat starchy foods.

But what about Harvard’s revised pyramid? Does following it 
provide better health results than following the USDA’s 
pyramid? 

To test it, the researchers devised their own index to 
measure how closely people in the study stuck with the 
eating habits prescribed by the new pyramid. “Applying this 
revised index to our epidemiological studies, we found that 
men and women who were eating in accordance with the new 
pyramid had a lower risk of major chronic disease,” Willett 
said.

So what’s different about the two pyramids? 

REBUILDING THE FOOD PYRAMID (1-2003)

Primarily, the USDA food pyramid is so oversimplified that 
it does not distinguish between different types of fats or 
different types of carbohydrates. It is based on the old 
mantra that “fat is bad,” and its corollary, “carbohydrates 
are good.”

In actuality, there are good fats and bad fats. The worst 
fats of all are the partially hydrogenated trans fats that 
are ubiquitous in margarine, shortening, and most store-
bought baked goods. Saturated fats were not found to be as 
bad as once thought. But monounsaturated fats, found in 
nuts and olive oil, are good for you, as are the essential 
omega-3 fatty acids found in fish and flaxseed. 

There are also differences in carbohydrates. Starches, 
sugars, and processed grains are bad, while high-fiber 
foods are nutritionally sound.

Willett’s new food pyramid puts exercise at its base. Above 
that are foods rich in the good fats and oils along with 
whole grain products, fruits and vegetables. Near the 
middle are nuts, poultry, and fish. And at the top are the 
highly-processed white-flour products, potatoes, sugar 
products, and saturated fats. Trans fats are left off the 
pyramid entirely because there is no place for them in the 
American diet.

Although the USDA is the agency that would be in charge of 
changing the nutrition recommendations, it might be a 
better idea to put someone else in charge. “The USDA may 
not be the best government agency to develop objective 
nutritional guidelines, because it may be too closely 
linked to the agricultural industry,” Willett said. 

Nutrition advice given to the public must be based on 
scientifically-valid information. It is time to rebuild the 
food pyramid to reflect what is now known about nutrition. 
And it’s time to let an economically-neutral agency, such 
as the National Science Foundation or the National 
Institutes of Health handle the recommendations. The USDA 
should stick to agricultural issues.