This Healthy Eating Pyramid Is Based On Science

Eat, Drink, and Be Healthy
by Walter C. Willett, M.D.

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You deserve more accurate, less biased, and more helpful information than that found in the USDA Pyramid. I have tried to collect exactly that in the Healthy Eating Pyramid. Without question, I have the advantage of starting with a lot more information than the USDA Pyramid builders had ten years ago. Equally important, I didn't have to negotiate with any special-interest groups when it came time to design this Pyramid.

The Healthy Eating Pyramid isn't set in stone. I don't have all the answers, nor can I predict what nutrition researchers will turn up in the decade ahead. But I can give you a solid sense of state-of-the-art healthy eating today and point out where things are heading. This isn't the only alternative to the USDA Food Guide Pyramid. The Asian, Latin, Mediterranean, and vegetarian pyramids promoted by Oldways Preservation and Exchange Trust are also good, evidence-based guides for healthy eating. But the Healthy Eating Pyramid takes advantage of even more extensive research and offers a broader guide that is not based on a specific culture.

About the only thing that the Healthy Eating Pyramid and the USDA Food Guide Pyramid share is their emphasis on vegetables and fruits. Other than that, they are different on almost every level. In the chapters that follow, I will lay out the evidence that shaped this blueprint for healthy eating and will also chart out extra information to help people with special nutritional needs get the most benefit from what they eat. These people include pregnant women, older people, and people with, or at high risk of, heart disease, diabetes, high cholesterol, high blood pressure, and some other chronic conditions.

For now, though, the following list of the seven healthiest changes you can make in your diet offers an overview that describes how the Healthy Eating Pyramid differs from the USDA Pyramid. Topping the list is controlling your weight.

• Watch your weight. When it comes to long-term health, keeping your weight from creeping up on you is more important than the exact ratio of fats to carbohydrates or the types and amounts of antioxidants in your food. The lower and more stable your weight, the lower your chances of having or dying from a heart attack, stroke, or other type of cardiovascular disease; of developing high blood pressure, high cholesterol, or diabetes; of being diagnosed with postmenopausal breast cancer, cancer of the endometrium, colon, or kidney; or of being afflicted with some other chronic condition. Yes, it is possible to be too thin, as in the case of anorexia nervosa, but otherwise very few American adults fall into this category.

• Eat fewer bad fats and more good fats. One of the most striking differences is the placement of healthy fats in the foundation of the Healthy Eating Pyramid instead of relegating all fats to the "Use Sparingly" spot at the top. The message here is almost as simple as the USDA's and far better for you: Fats from nuts, seeds, grains, fish, and liquid oils (including olive, canola, soybean, corn, sunflower, peanut, and other vegetable oils) are good for you, especially when you eat them in place of saturated and trans fat.

The all-fat-is-bad message has started a huge national experiment, with us as the guinea pigs. As people cut back on fat, they usually eat more carbohydrates. In America today, that means more highly refined or easily digested foods like sugar, white bread, white rice, and potatoes. This switch usually fails to yield the hoped-for weight loss or lower cholesterol levels. Instead it often leads to weight gain and potentially dangerous changes in blood fats — lower high-density lipoprotein (HDL), the so-called good or protective cholesterol, and higher triglycerides (a major type of blood fat).

Substituting unsaturated fats for saturated fats, though, improves cholesterol levels across the board. It may also protect the heart against rhythm disturbances that can end in sudden death.

The bottom line is this: It is perfectly fine to get more than 30 percent of your daily calories from fats as long as most of those fats are unsaturated. The Healthy Eating Pyramid highlights the importance of keeping saturated and trans fats to a minimum by putting red meat, whole-milk dairy products, butter, and hydrogenated vegetable oils in the "Use Sparingly" section at the top.

• Eat fewer refined-grain carbohydrates and more whole-grain carbohydrates. The Healthy Eating Pyramid has two carbohydrate building blocks — whole grains that are slowly digested as part of the foundation and highly refined, rapidly digested carbohydrates at the very top.

For almost twenty years our research team has been one of several groups studying the health effects of foods made from refined and intact grains. The result of this work is compelling. Eating lots of carbohydrates that are quickly digested and absorbed increases levels of blood sugar and insulin, raises levels of triglycerides, and lowers levels of HDL cholesterol. Over the long run, these changes lead to cardiovascular disease and diabetes. In contrast, eating whole-grain foods is clearly better for long-term good health and offers protection against diabetes, heart disease, cancer, and gastrointestinal problems such as diverticulosis and constipation. Other research around the world points to the same conclusions.

• Choose healthier sources of proteins. In the Healthy Eating Pyramid, red meat occupies the pointy tip to highlight the fact that something about red meat — its particular combination of saturated fats or the potentially cancer-causing compounds that form when red meat is grilled or fried — is connected to a variety of chronic diseases. In this pyramid, the best sources of protein are beans and nuts, along with fish, poultry, and eggs. It separates vegetable and animal protein sources and makes the latter optional for people who want to follow a vegetarian diet.

• Eat plenty of vegetables and fruits, but hold the potatoes. Vegetables and fruits are essential ingredients in almost every cuisine. If you let them play starring roles in your diet, they will reward you with many benefits besides great taste, terrific textures, and welcome variety. A diet rich in fruits and vegetables will lower your blood pressure, decrease your chances of having a heart attack or stroke, help protect you against a variety of cancers, guard against constipation and other gastrointestinal problems, and limit your chances of developing aging-related problems like cataracts and macular degeneration, the most common causes of vision loss among people over age sixty-five. I've plucked potatoes out of the vegetable category and put them in the "Use Sparingly" category because of their dramatic effect on levels of blood sugar and insulin.

• Use alcohol in moderation. When the first reports appeared linking moderate alcohol consumption with lower rates of heart disease, many scientists thought that some other habit shared by drinkers, not the drinking, accounted for the benefit. Today the evidence strongly points to alcohol itself. Based on the best estimates available, one drink a day for women and one or two a day for men cuts the chances of having a heart attack or dying from heart disease by about a third and also decreases the risk of having a clot-caused (ischemic) stroke.

Like many drugs, alcohol's effects depend on the dose. A little bit can be beneficial. A lot can eventually destroy the liver, lead to various cancers, boost blood pressure, trigger so-called bleeding (hemorrhagic) strokes, progressively weaken the heart muscle, scramble the brain, harm unborn children, and damage lives.

The clear and ever present dangers of alcohol and alcohol addiction make the recommendation of moderate drinking a political hot potato. While I acknowledge the problems with alcohol, I think it is important to point out its possible benefits for middle-aged and older people.

If you don't drink alcohol, you shouldn't feel compelled to start. You can get similar benefits by beginning to exercise (if you don't already) or boosting the intensity and duration of your physical activity, in addition to following the eating strategy we describe. But if you are an adult with no history of depression or alcoholism who is at high risk for heart disease, a daily alcoholic drink may help reduce that risk. This is especially true for people with type 2 diabetes or those with low HDL that just won't budge upward with diet and exercise. If you already drink alcohol, keep it moderate.

• Take a multivitamin for insurance. Several of the ingredients in a standard multivitamin — especially vitamins B₆ and B₁₂, folic acid, and vitamin D — are essential players in preventing heart disease, cancer, osteoporosis, and other chronic diseases. At about a nickel a day, a multivitamin is a cheap and effective genuine "life insurance" policy. It won't make up for the sins of an unhealthy diet, but it can fill in the nutritional holes that can plague even the most conscientious eaters. A daily multivitamin is especially important for people who have trouble absorbing vitamins from their food and for those who can't, or don't, get out in the sun every day. A daily multivitamin is also important for people who drink alcohol because it provides extra folic acid. Alcohol interferes with the metabolism of this key vitamin.

USDA Pyramid and Dietary Guidelines Fail the Health Test

Throughout this book I will talk about "the evidence." I hope I won't sound like an old, scratched record, repeating that there is or is not enough evidence on the benefits or risks of this or that strategy. But the evidence is what matters. Without it, recommendations are little more than opinions and educated guesses, and they may or may not accomplish what they set out to do.

In the ten years since the USDA Pyramid was designed and built, it has never been updated to reflect the wealth of new information that's become available on diet and health. Nor has it ever been tested to see if it really works. Until now.

A few years ago, the USDA's Center for Nutrition Policy and Promotion devised a score sheet called the Healthy Eating Index "to measure how well American diets conform to recommended healthy eating patterns." This index assigns scores of 0 to 10 for each of ten dietary components. Five come from the USDA Pyramid (number of daily servings of grains, vegetables, fruits, meat, and dairy products), and five come from the Dietary Guidelines for Americans (total fat in the diet, percentage of calories from saturated fat, cholesterol intake, sodium intake, and variety of the diet). A score of 100 would mean perfect adherence to the USDA's recommendations, while a score of 0 would mean total disregard for them.

My colleagues and I used the government's Healthy Eating Index to test whether people who follow the recommendations laid out in the USDA Pyramid are healthier than those who don't follow these guidelines. They aren't. Among over 121,000 female nurses who are participating in a long-term study of diet you'll be hearing more about in later chapters, those with the highest scores on the Healthy Eating Index were no less likely to develop a major illness or die than those with the lowest scores over a twelve-year period. Women scoring high on the Healthy Eating Index were only slightly less likely to have a heart attack. The pattern was similar for more than 50,000 male health professionals participating in a separate long-term study.

These dismal results shouldn't come as a surprise since the USDA Pyramid ignores the extensive body of evidence linking certain eating patterns with long-term health. Instead they should be a warning that the current USDA Pyramid won't help you eat to live well or live longer.

To be fair, we are now in the process of testing the Healthy Eating Pyramid. Because each of its building blocks comes from the finest possible quarry — solid evidence amassed by researchers from around the world — it has already passed the most important tests. I'm confident that the findings from this research will show that it can help keep you healthy.

What's In This Book

Between the covers of this book is the latest thinking about diet and health. To give you a quick and easy guide, I distilled as much information as possible into the Healthy Eating Pyramid. But I also wanted you to see the blueprint — the scientific evidence — on which it is based. This is detailed in chapters 3 through 11. Along the way, I describe cutting-edge research that may radically change healthy eating patterns, including new information on the benefits of n-3 fatty acids found in some oils and nuts; on lycopene, a possible cancer-fighting substance found in tomatoes; on the potential hazards of getting too much calcium; and on why it makes sense to take a daily multivitamin.

This book also helps you incorporate this information into your snacks and meals with practical tips on buying healthy foods and eating defensively and a section that offers more than fifty tested, tasty recipes.

This information isn't meant to take the place of advice you get from your physician, especially if you have a medical condition that requires a specific diet. Instead I encourage you to talk about your diet with your health care provider or share what you've learned from this book with her or him to make sure you are on the same wavelength. Unfortunately, the pressures of modern medicine and health care often make it difficult for clinicians to spend time talking about healthy food choices with their patients.

Copyright © 2001 by the President and Fellows of Harvard College

About the Author

Walter C. Willett, M.D., is chairman of the Department of Nutrition at the Harvard School of Public Health and a professor of medicine at the Harvard Medical School. A world-renowned researcher, he is one of the leaders of the famous Nurses' Health Study and Health Professionals Follow-up Study. Dr. Willett has won many honors, including the Mott Prize, the prestigious award of the General Motors Cancer Research Foundation.