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  This dismal result shouldn’t come as a surprise, since the USDA consistently ignored the extensive body of evidence linking certain eating patterns with long-term health. Take it as a warning that following the Department of Agriculture’s advice may not help you eat to live well or live longer.

  A MEDITERRANEAN EXPERIMENT

  One strand of this evidence came from Greece. In the 1980s, Greek men lived four years longer than American men and had remarkably low rates of heart disease despite a relatively basic health care system. Their diet was thought to have something to do with this. (Note: The term “heart disease” encompasses a wide range of conditions ranging from chest pain to electrical problems in the heart and failure of the heart muscle to pump blood. In this book, the term heart disease refers to coronary artery disease, which stems from a blockage in one or more arteries that supply blood to the heart.)

  My colleagues and I began working with other scientists who were deeply knowledgeable about traditional Greek cuisine as well as with experts with Oldways, an organization focused on creating healthier, tradition-based alternatives to the USDA’s Food Guide Pyramid. Together we created in 1993 a pyramid to represent the traditional Mediterranean diet.7 It was built on a base of healthy whole grains, fruits, vegetables, beans, and healthy fats. At the time it was widely criticized by many in the nutrition community because it was high in fat, mainly olive oil. Since then, various streams of evidence have confirmed that olive oil is a healthy source of calories (see chapter five).

  Antonia Trichopoulou and her husband, Dimitrios Trichopoulos, the Greek colleagues and friends who helped us create the Mediterranean Diet Pyramid, then embarked on a more formal study of the Greek diet. They created a simple score to describe the traditional eating pattern of Greece. Points were given to higher intakes of olive oil, vegetables, legumes, fruits and nuts, cereal, and fish; lower intakes of meat, poultry, and dairy foods; and moderate alcohol consumption. They tested the score in a population of 22,000 Greek men and women whose diets and health were followed from 1994 to 1999. Those who most closely stuck with a traditional diet were less likely to have died prematurely and to have died from heart disease and cancer.8 Later evaluations of the Mediterranean dietary score in populations around the world have confirmed its correlation with the development of many chronic diseases and lower risks of death.

  Ten years later, Spanish colleagues of ours put the Mediterranean diet to the test in a randomized trial called PREDIMED.9 They assigned nearly 7,500 men and women to either a Mediterranean diet with added nuts or extra-virgin olive oil or to a low-fat diet. After an average of five years, those who had been following the Mediterranean diet had a 30 percent lower rate of cardiovascular disease compared with those in the low-fat group. Further analyses showed that those following the Mediterranean diet also had lower rates of diabetes and breast cancer, and better cognitive function.

  IN WITH THE NEW: THE HEALTHY EATING PYRAMID

  Americans deserve more accurate, more helpful, and less biased information than what’s offered by the federal government. To right the wrongs of the Food Guide Pyramid, my colleagues and I used the data we had, bolstered by the work in Greece, to create the Healthy Eating Pyramid (page 16) in 2000. It sits on a foundation of daily exercise and weight control. We then added the building blocks of a healthy diet, with each block supported not just by our own studies but also by the best of science from around the world. The blocks of the Healthy Eating Pyramid include:

  • vegetable oils such as olive and canola oil as the primary sources of fat

  • an abundance of vegetables and fruits, not including potatoes or corn

  • whole-grain foods at most meals

  • healthy sources of protein such as beans, nuts, seeds, fish, poultry, and eggs

  • a daily calcium supplement or dairy foods one to two times a day

  • a daily multivitamin

  • for those who choose to drink, alcohol in moderation

  • red meat, white bread, potatoes, soda, and sweets only occasionally if at all.

  The Healthy Eating Pyramid, unlike the USDA’s Food Guide Pyramid, didn’t specify how many ounces or cups of specific foods you should have each day. That depends on your body size and physical activity. It also didn’t describe percentages of calories from fat, carbohydrate, or protein, because there is no scientific basis for setting specific numbers. Also, in reality, it is very difficult for anyone to know if they are exceeding a specific percentage. These changes made the Healthy Eating Pyramid easier to use than the USDA pyramid.

  There was just one key guideline to remember: Choose more foods from the lower parts of the pyramid than from its upper levels. Eating mostly minimally processed, whole foods from the lower part of the Healthy Eating Pyramid provides the balance of nutrients an individual needs and limits health-damaging foods.

  THE HARVARD HEALTHY EATING PYRAMID

  Figure 3. The Harvard Healthy Eating Pyramid. This pyramid, based on solid science, offers better guidance for healthy eating than the advice from the USDA.

  We put the Healthy Eating Pyramid to the same test that we applied to the USDA Pyramid. We first created an Alternate Healthy Eating Index based on the Healthy Eating Pyramid. It included indicators such as intake of vegetables, fruits, nuts, cereal fiber, trans fats, and alcohol, multivitamin use, and the ratios of white to red meat and unsaturated fat to saturated fat. Using the same information from the 135,000 women and men described earlier, we calculated Alternate Healthy Eating Index scores for each individual. Women and men with high scores (those who followed the eating strategies embodied in the Healthy Eating Pyramid) had substantially lower risks of developing major chronic diseases, especially heart disease or stroke, than those scoring low on the index.10

  My colleagues and I were pleased by these results. But we weren’t entirely surprised, because each building block of the Healthy Eating Pyramid came from the finest possible quarry: solid evidence amassed by researchers from around the world. Seventeen years later, it is standing the test of time, as much new evidence has provided further support for it.

  THE USDA PYRAMID GETS A MAKEOVER

  Taking a cue from television reality shows, the federal government gave the Food Guide Pyramid an extreme makeover in 2005. In doing this, it squandered what could have been an opportunity to overhaul and correct the faults of the original. Working again with Porter Novelli, the USDA tipped the pyramid on its side, painted it in a rainbow of brightly colored bands running vertically from the tip to the base, and chiseled a jaunty stick figure running up stairs on its left side. That was it—no labels, no text, no key to help you decipher what it means. To understand what the new pyramid, dubbed MyPyramid, was saying, you needed a computer and a connection to the Internet.

  MyPyramid didn’t right the wrongs of its predecessor, nor did it offer any real information to help us make healthy choices. That was unfortunate, because the 2005 Dietary Guidelines themselves were inching closer to the dietary pattern described by our Healthy Eating Pyramid. The 2005 guidelines acknowledged the harmful effects of trans fat and the beneficial role of vegetable oils, and they emphasized the importance of whole grains. However, they still capped total fat intake and promoted consuming large amounts of starch.

  USDA’S NEW MYPYRAMID

  Figure 4. MyPyramid. In 2005, the USDA unveiled its catchy but information-free replacement for the familiar Food Guide Pyramid.

  At best, MyPyramid was a missed opportunity to improve the health of millions of people. At worst, the lack of information and misinformation it conveyed contributed to overweight, poor health, and unnecessary early deaths.

  Once again, special interest lobbies took the lead, shoving science aside.

  FROM PYRAMID TO PLATE

  Bowing to criticism that MyPyramid was vague and confusing, the USDA replaced it in 2011 with MyPlate. This colorful image of a dinner plate divided into quarters makes an important and healthful point: Fill half your plate with ve
getables and fruits. The other two quarters say little beyond “Eat more grains than protein.” MyPlate says nothing about the quality of carbohydrates (grains). It makes no distinction between healthy sources of protein, such as beans, fish, and poultry, and less healthy sources such as red and processed meat. It recommends milk or dairy at every meal, even though there is little evidence that high dairy intake protects against osteoporosis and substantial evidence that consuming a lot of milk and dairy foods can be harmful. It offers no advice about healthy oils, which are good for the heart, arteries, and the rest of the body. And it is shockingly silent on sugary drinks, which provide far too many empty calories.

  As we did with the Food Guide Pyramid, my colleagues and I created an alternative to MyPlate based on the most up-to-date research. The Harvard Healthy Eating Plate offers specific guidance for a healthy diet that complements the Healthy Eating Pyramid and translates it to the context of a meal. As described in later chapters, it can help you improve the quality of your diet. Specifically, the Healthy Eating Plate recommends eating whole grains instead of refined grains, describes healthy sources of protein that don’t include red meat, eliminates potatoes from the vegetable group, provides guidance about healthy sources of fat, and recommends water or other healthy beverages with every meal instead of milk.

  MYPLATE

  Figure 5. The USDA launched MyPlate in 2011.

  THE HARVARD HEALTHY EATING PLATE

  Figure 6. The Harvard Healthy Eating Plate offers simple guidance for making the best eating choices.

  Think of the Healthy Eating Plate as a simple guide for creating healthy, balanced meals, whether served on a plate or packed in a lunch box. It complements the Healthy Eating Pyramid, which can be used more as a grocery list. Fill your cart with items that populate its base, like vegetables, fruits, whole grains, healthy oils, and healthy sources of protein such as nuts, beans, fish, and chicken. Go easy on those near the top, such as red meat, white bread and other highly processed carbohydrates, sugar-sweetened beverages, and other sweets. Then, when you return home, prepare a meal that draws inspiration from the Healthy Eating Plate.

  The Healthy Eating Plate is now available in dozens of different languages, and a children’s version is also available. You can find all versions of the Plate at www.hsph.harvard.edu/nutritionsource/healthy-eating-plate/.

  2015–2020 DIETARY GUIDELINES: PLENTY OF MEDDLING

  To develop the 2015–2020 Dietary Guidelines for Americans, the USDA and the U.S. Department of Health and Human Services made an extra effort to minimize industry conflicts of interest. They appointed scientists without ties to lobbyists to serve on the Dietary Guidelines Advisory Committee. They also developed more specific rules for reviewing published studies to ensure that these scientists included all relevant evidence, a process called a systematic review. The committee members worked for two years, all as unpaid volunteers, to develop a comprehensive, science-based 571-page report.11

  The recommendations in that report are very close to what Eat, Drink, and Be Healthy first recommended in 2001 and what it still recommends today. The Dietary Guidelines Advisory Committee emphasized healthy overall dietary patterns, including a Mediterranean-type diet, a vegan diet, and an eclectic healthy American diet. One important change from the previous Dietary Guidelines for Americans was the removal of an upper limit for total fat consumption, earlier set at 30 percent and then 35 percent of calories. I congratulate the advisory committee for correctly concluding that there was no evidence to support a specific upper limit. This is an important step, because the caps on total fat in the past led to promoting foods high in carbohydrates that were mostly refined starch and sugar.

  After reviewing the abundant new evidence, the 2015–2020 Dietary Guidelines Advisory Committee explicitly recommended:

  • limiting red meat consumption for both individual and planetary health

  • reducing sugar intake to less than 10 percent of calories

  • greatly reducing consumption of soda and other sugar-sweetened beverages.

  The cattle and soda industries were furious about the recommendations. They put their powerful lobbies to work on Capitol Hill. The result was language embedded in the final government appropriations bill that forbade the USDA from including any statements in the final Dietary Guidelines for Americans about the environmental effects of dietary choices.

  The lobbyists also had a supporter at the USDA, its head, Secretary Tom Vilsack. This former governor of Iowa has longstanding connections to the corn and pork industries. Even though Congress allowed the USDA to accept the recommendations of the Dietary Guidelines Advisory Committee to limit consumption of red and processed meat, the final Dietary Guidelines for Americans didn’t mention that. Instead, it promoted consumption of red meat as long as it was lean, a finding not based on any evidence. The clear statement from the Dietary Guidelines Advisory Committee about reducing consumption of sugar-sweetened beverages was also considerably watered down.

  The process of creating the 2015–2020 Dietary Guidelines vividly exposed the power of the agriculture and food industries in shaping dietary advice. The report of the advisory committee was censored. It was corrupted as it was “translated” into the official Dietary Guidelines for Americans that form the basis of federal food policy. These are the guidelines that our children learn in school.

  The 2015–2020 Dietary Guidelines Advisory Committee report was a major advance in bringing advice on healthful eating in line with scientific evidence. But it still left some room for future improvements. The committee was told that its recommendations must meet the recommended dietary allowances (RDAs) for vitamins and minerals set by the Institute of Medicine (now called the National Academy of Medicine). That’s a problem, because RDAs are often based on fragments of evidence and, for some nutrients, are seriously out-of-date.

  Another problem with basing recommendations on RDAs is that the benefits of a food shouldn’t be based simply on how much of a single nutrient it contains. This led to recommendations for high consumption of milk, which I discuss in chapters nine and ten.

  The 2015–2020 advisory committee followed its predecessors by continuing to include potatoes as a vegetable despite substantial evidence that the health implications of eating potatoes are different than those of eating vegetables (see “The Spud Is a Dud” on page 167). Some experts challenged the advisory committee’s decision to deemphasize the importance of limiting dietary cholesterol and eggs, a matter of judgment that I will talk about in chapter five.

  That said, the committee deserves much credit for producing the most scientifically based report so far. It’s highly unfortunate that their evidence-based recommendations weren’t faithfully translated in the final dietary guidelines that guide policy and shape the eating habits of millions of Americans.

  FURTHER TESTING OF THE PYRAMIDS, PLATES, AND DIETARY GUIDELINES

  Back in 1995 the USDA created what it called the Healthy Eating Index. This ten-item score tried to measure how healthfully Americans were eating. The first five items checked how well a person’s diet conformed to the Food Guide Pyramid for grains, vegetables, fruits, milk, and meat. The next four checked total fat in the diet, saturated fat, cholesterol, and sodium. The tenth measured the amount of variety in the diet. Each item was awarded 0 to 10 points: the higher the number, the more closely an individual was following the USDA’s guidelines for healthy eating.

  My colleagues and I, having highlighted the deep flaws in the USDA’s dietary recommendations, put the Healthy Eating Index to the test among the participants of the Nurses’ Health Study and the Health Professionals studies. Individuals with high scores were only slightly less likely to have had heart attacks or strokes, and there was no reduction in cancer. In other words, those who most closely followed the government’s recommendations didn’t fare much better than those who did.

  What if such a diet-measuring tool made a distinction between healthful unsaturated fat and less-than-h
ealthy saturated fat, or the main sources of carbohydrates or protein? So we devised the Alternate Healthy Eating Index in 2002.12 It recorded nine diet items: servings of vegetables, fruits, and nuts or soy protein a day; grams of fiber from grains; the ratio of white to red meat; the amount of trans fat; the ratio of polyunsaturated to saturated fat; use of a multivitamin; and daily alcohol consumption. Like the Healthy Eating Index, points were awarded for each item, with higher points representing healthier choices.

  When we compared the two indexes using diet data from the Nurses’ Health Study and the Health Professionals Follow-Up Study, the Alternative Healthy Eating Index was far better at predicting the development of cardiovascular disease and other chronic conditions than the USDA’s Healthy Eating Index.13 That means we can further reduce the risk of cardiovascular disease, cancer, and other chronic conditions by following evidence-based dietary guidance rather than government-based guidance.

  New evidence on diet and health prompted my colleagues and me to make small adjustments to our Alternative Healthy Eating Index. With the most recent update, in 2010, we added to the index, limiting soda and other sugar-sweetened beverages as a healthy eating strategy. We repeated our test to determine if women and men whose diets fit the pattern described by this index—which matches the recommendations in this book—have better long-term health and compared it to an updated version of the USDA’s Healthy Eating Index that more closely resembles our Alternative Index.

  As expected, both of these indices represent dietary advice and eating patterns that are in line with lower risks of dying prematurely or developing heart disease, type 2 diabetes, and other chronic conditions. Even so, our Alternative Healthy Eating Index did better than the USDA’s.14