Eat, Drink, and Be Healthy
Page 33
• taking a daily multivitamin for insurance.
At first glance, it might look like I am promoting a traditional Mediterranean diet. While the Mediterranean diet fits this description, and is an excellent place to start, what I suggest isn’t limited to the culinary experience of just one place or time. Instead, this strategy is a science-based, multicultural approach to healthy eating.
THE HARVARD HEALTHY EATING PYRAMID
Figure 21. The Harvard Healthy Eating Pyramid, based on solid science, offers better guidance for healthy eating than advice from the USDA.
BENEFITS OF THIS EATING STRATEGY
Part of the payoff from following this healthy eating strategy comes immediately. By opening up a new world of foods, flavors, and textures, it will make eating a pleasure. It can help you break out of the often unsatisfying and not-so-healthy mealtime ruts you can fall into when following a low-fat or low-carb diet. As you gain control of your appetite and eating habits, not to mention your weight, cholesterol levels, and maybe even your blood pressure, you’ll gain a sense of achievement and pride that may affect other areas of your life. You’ll also have more energy and feel better right now as well as years down the road.
The other part of the payoff—protection against chronic disease—comes later. A healthful eating strategy like the one I suggest can help protect you from developing a long list of common diseases. These include heart disease, stroke, type 2 diabetes, several common cancers, cataracts, osteoporosis, dementia, and other age-related diseases. It also helps prevent some types of birth defects. When combined with not smoking and regular exercise, this kind of healthy diet can reduce heart disease by 80 percent, type 2 diabetes by 90 percent, and stroke and some cancers by 70 percent, compared with average rates in the United States.1
To borrow a phrase from the financial world, that’s a great return on investment, especially when the investment is a more flavorful and less restrictive version of what you may be eating today.
THE HARVARD HEALTHY EATING PLATE
Figure 22. The Harvard Healthy Eating Plate was created to address deficiencies in the USDA’s MyPlate. It provides simple but detailed guidance to help people make the best eating choices.
THE ROMANCE AND REALITY OF TRADITIONAL DIETS
The term “traditional diet” once meant a plain, none-too-varied regional diet that was the standard fare of farmers and laborers. Today it conjures up images of heart-healthy, cancer-free, long-lived people who understand the land, eat wonderful meals brimming with taste, and dance, drink, laugh, and love. Think Zorba the Greek meets Julia Child.
A lot of popular writing implies that the foods that go into traditional diets have been carefully chosen over the years to promote good health. That’s not so. People ate what they could grow, gather, kill, or buy, and their choices were dictated by weather, geology, geography, economics, and even politics. Given these constraints, different cultures have developed various combinations of healthy (and sometimes not-so-healthy) foods. Keep in mind that these choices were made for short-term health, not for prolonging life into old age. Also keep in mind that diets that seem to be good for people whose days are full of hard physical labor aren’t necessarily good for people who toil at a desk all day.
In northern Europe, for example, the short growing season makes it difficult to eat fruits and vegetables year-round. It is, however, a fine climate for raising livestock, and meat and dairy foods made a good match for the energy needs of people who had to survive long, cold winters. In the small island nation of Japan, the main components of the diet are fish, naturally, and rice, a plant that can yield large amounts of grain from small plots of land. In both these cases the traditional diet kept people healthy long enough to reproduce and raise children and also to develop complex societies. Yet their successes don’t imply that either of these diets would yield the best health for contemporary people who sit most of the day.
THE MEDITERRANEAN DIET AND BEYOND
In the 1950s and 1960s, pioneering nutrition researcher Ancel Keys and his colleagues looked at eating patterns in sixteen different populations in seven countries: Greece, Finland, Italy, the Netherlands, Yugoslavia, Japan, and the United States. This landmark work, known today as the Seven Countries Study, was the first major investigation of the link between diet and heart disease. One of the more intriguing findings was that people living in Crete, other parts of Greece, and southern Italy had very high adult life expectancies (the number of years the average forty-five-year-old can expect to live) and very low rates of heart disease and some cancers, all in spite of relatively limited medical systems.2 (See the tables on page 254.)
At the time, the traditional diet in these Mediterranean countries was mostly plant-based foods: fruits, vegetables, breads, a variety of coarsely ground grains, beans, nuts, and seeds. Olive oil was the main source of dietary fat. People regularly ate dairy foods—mostly cheese and yogurt—but not in large amounts. Fish, poultry, and red meat were eaten on special occasions, not as part of the daily fare. People, usually men, often drank wine, but typically with meals.
Keys concluded that the Mediterranean diet was an important reason for the low rates of heart disease in that region. Alarmed at the epidemic of heart disease that was hitting its peak in the United States in the 1960s, Keys and his wife, Margaret, began popularizing and promoting the Mediterranean diet in a series of bestselling books.3
Characteristics of Diets in the 1960s of Three Countries in the Seven Countries Study
* * *
Diet*
U.S.
Greece
Japan
Total fat (% energy)
39
37
11
Saturated fat (% energy)
18
8
3
Fruits and vegetables (grams/day)
504
654
232
Legumes (grams/day)
1
30
91
Breads, cereal grains (grams/day)
123
453
481
Meat and poultry (grams/day)
273
35
8
Fish (grams/day)
3
39
150
Eggs (grams/day)
40
15
29
Alcohol (grams/day)
6
23
22
* Since the 1960s, consumption of red meat and animal fat has greatly increased in Japan and Greece.
Comparison of Life Expectancy and Disease Rates in the 1960s of Three Countries in the Seven Countries Study*
* * *
Life Expectancy and Disease Rates
Gender
U.S.
Greece
Japan
Life expectancy at age 45 (1960s)
M
F
72
78
76
79
72
77
Heart disease (per 100,000 people)
M
F
189
54
33
14
34
21
Stroke (per 100,000 people)
M
F
30
24
26
23
102
57
Colorectal cancer
M
F
11
10
3
3
5
5
All cancers (per 100,000 people)
M
F
102
87
83
61
98
77
Breast cancer (per 100,000 people)
F
22
8
4
* Since the 1960s the rates of stroke and stomach cancer have decreased in Japan; life expectancy at age 45 is now greatest in that country (87.7 years for females and 81.8 years for males), followed by Greece (84.6 years for females and 80.1 years for males), and the United States (83.3 years for females and 79.6 years for males).
Source: Willett, W. C., “Diet and Health: What Should We Eat?” Science 264, no. 5158 (April 22, 1994): 532–7.
The Seven Countries study raised the possibility that the Mediterranean diet could be a cause of long life and good health. But it couldn’t prove it had that effect. Other things—such as the physically active lifestyle common throughout the region, the relatively low rates of overweight and obesity, or the low rates of smoking that prevailed until the late 1960s—could have been among the causes. It was also possible that some genetic trait common among people in the Mediterranean region provided them with protection against heart disease and cancer, although this explanation was discounted by studies showing that people lose their protection when they migrate from countries where heart disease, cancer, and diabetes are rare to countries where they are common.
Evidence accumulated over the last fifty years shows that Keys and his colleagues were on the right track. My research group, for example, has documented that the main elements of the Mediterranean lifestyle are connected with lower risks of many diseases even when followed by people living away from the Mediterranean region. Results from the Nurses’ Health Study document that heart disease rates in the United States could be reduced by least 80 percent by modest changes in diet and lifestyle changes.4 The Lyon Diet Heart Study, described in chapter five, showed that a group of heart attack survivors randomly assigned to a Mediterranean-type diet were 70 percent less likely to die over a two-year period than those assigned to the low-fat diet advocated by the American Heart Association.5 More recently, our colleagues in Spain showed in a randomized trial that a Mediterranean diet with added nuts or olive oil reduced cardiovascular disease risk by 30 percent compared to a low-fat diet.6 Today the Mediterranean diet is often held up as a prime example of healthy eating that should be adopted by all. It was even recognized in the 2015–2020 Dietary Guidelines for Americans as an example of a desirable dietary pattern!7
But the Mediterranean diet isn’t necessarily perfect. It evolved out of agricultural necessities imposed by a warm and semidry climate that, by chance, favored the growth of olive trees. And it isn’t the only healthy culture-based diet. A traditional Japanese diet can be quite healthy. Traditional Latin American diets, which emphasize corn, beans, and vegetables, can provide another model of healthy eating. But keep in mind that the corn we eat today is not the same as the corn eaten one hundred years ago, and that large amounts of corn may not be healthy for individuals who aren’t physically active.
Along with a diverse group of colleagues, I helped Oldways Preservation and Exchange Trust create a series of food pyramids that tried to capture the traditional healthy diets of these regions (www.oldwayspt.org/traditional-diets).
As researchers continue to define more precisely the specific health-promoting elements of a Mediterranean-type diet, one thing we know for sure is that it is safe. The low rates of heart disease and cancer among people who have eaten this type of diet for thousands of years are solid proof of that. The high rate of strokes in Japan, on the other hand, suggest that some aspect of that traditional diet, possibly high carbohydrate and salt intake combined with low consumption of healthy fats, protein, fruits, and vegetables, may not be so safe.
TRADITIONAL DIETS CAN TRANSPLANT WELL
While traditional diets may have health benefits for the cultures that shaped them, a big question is whether they offer similar benefits when transplanted somewhere else, like a modern society with relatively low levels of physical activity. If traditional diets are like weeds that can grow anywhere, then an Iowa accountant should get the same benefit from a Mediterranean diet as a Greek farmer. But if traditional diets are more like painstakingly bred orchids that grow only in carefully controlled environments, then adopting a traditional diet without also taking on the other aspects of the traditional culture won’t necessarily make a dent in rates of heart disease, cancer, and other chronic diseases.
Fortunately, evidence from different types of studies done in many countries shows that the components of a Mediterranean-type diet offer major benefits even for people living modern “Western” lifestyles.8 It remains to be seen whether dining leisurely with a view of the Aegean Sea or taking a siesta after a midday meal adds an extra topping of good health.
Scientists, nutrition experts, and writers have often tried to condense the benefits of the Mediterranean or other traditional diets into one or two key elements, like olive oil or fiber or antioxidants. That’s a dangerous proposition. While we know that the Mediterranean diet helps prevent chronic disease, and that olive oil is one of the reasons why, just loading up on olive oil or taking high-dose antioxidant supplements isn’t a substitute for a comprehensive healthy eating strategy.
Most important, taking advantage of the Mediterranean diet isn’t an all-or-nothing proposition. We know enough about this diet to be sure that its elements can be safely and fruitfully incorporated into other healthy eating strategies.
COST OF HEALTHY EATING
Does it cost more to eat foods that promote good health than to eat those that don’t? Many people believe that nutritious foods are more expensive than less healthy alternatives. They are partly right. Fats, sugar, and refined carbohydrates deliver more calories per dollar than fish or fresh vegetables.9 Yet, when it comes to an all-around diet, cost need not stand in the way of healthy eating. And keep in mind that the traditional Mediterranean diet was originally the diet of poorer people, not the wealthy.
Following a healthy eating pattern is all about choices: picking good fats and steering clear of bad ones, adding more good sources of carbohydrate and cutting back on poor ones, opting for healthier protein packages, selecting smaller portions instead of super-sizing, and so on. Cost, along with taste and convenience, is an important factor influencing these choices.
Foods that are filling, high in calories, and satisfying are often the least expensive. In day-to-day eating and shopping, this means that a hamburger and french fries washed down with a large soda and topped off with soft-serve ice cream is a relatively inexpensive way to get calories. Foods that pack the most calories per ounce—those with the highest energy densities—tend to have the lowest cost per calorie. These include oil, margarine, sweets, and soft drinks. Healthier options, such as whole grains, fresh fruits and vegetables, and fish, cost more per calorie.
For people with limited incomes, market forces seem to conspire against healthy eating. If you’re at the other end of the spectrum, you can pay top dollar for out-of-season fruits and vegetables, ready-to-eat packages of salad, top-of-the-line fish, and specialty breads. In between those extremes is the vast middle ground that most of us try to navigate as we make our way through the grocery store or market. Here are some suggestions for anyone interested in making healthy choices without breaking the bank.
Fats. There’s no question that extra-virgin olive oil is more expensive than canola or soybean oil. Even so, you can find some perfectly tasty types for $8 to $10 a liter. At two tablespoons a day, that’s less than 50 cents. From a health perspective, we can’t say that olive oil is superior to canola or soybean oil. All are healthy fats, but we have longer-term experience with olive oil. Use olive oil where its flavor counts, such as for drizzling on vegetables or in salad dressings. Otherwise, use canola oil or other liquid plant oils for sautéing or other applications where flavor isn’t as important.
Carbohydrates. White rice, pasta, and potatoes are some of the least expensive sources of carbohydrate. Whole grains, such as brown rice, bulgur, wheat berries, oat groats, and others, cost more—although they really shouldn’t, because they require less processing. Yet, when you calculate the cost per serving, using who
le grains adds relatively little to the food budget. Whole-grain breakfast cereals, especially oatmeal or other cooked whole grains, can be excellent choices as long as you stay away from those that deliver a lot of added sugars.
Protein. When Americans think of protein, they tend to think of meat. Beef is certainly a major protein source. Turkey and chicken offer a more healthful protein package and are typically less expensive. Roasting a whole chicken is an inexpensive main dish that also offers plenty of leftover options. Fish is an even healthier protein source. Some types, such as swordfish and sole, are budget breakers or once-in-a-while luxuries. Others are more reasonably priced and are often on sale. These include tilapia, catfish, pollock, and many types of frozen fish. Canned tuna, salmon, and mackerel—on a sandwich, in a salad, or as part of a casserole—are inexpensive ways to put fish on your plate. Canned salmon delivers the most omega-3 fats per dollar and is also very low in mercury, which is important for women who are pregnant or breastfeeding.
Eating even lower on the food chain is usually the best for your budget and your health. Making nuts, peanuts, peanut butter, beans, tofu, other vegetable sources of protein, and eggs the centerpiece of meals, instead of side dishes or garnishes, would be a boon for your budget. Don’t be put off by the cost of nuts. Keep in mind that meat is two-thirds water, so nuts that cost $7.50 per pound are comparable to beef that costs $2.50 per pound. If you think about it this way, peanuts are a real bargain.
Fruits and vegetables. Even though fruits and vegetables don’t deliver the cheap caloric punch of fats and sugar, they can still be a good bargain. Consider what’s in season when shopping, both for price and quality. The USDA calculates that a savvy shopper can meet the recommendations for fruits and vegetables in the 2015–2020 Dietary Guidelines for Americans for under $3 a day.10 My family has found that it is possible for much less. Vegetables that are quite inexpensive per serving include cabbage, winter squash, and carrots; with the right seasoning and oils, these are delicious. Frozen fruits and vegetables are just as nutritious as fresh ones, and often cost less. Out of season, dried fruit can be a good option.