Photography by Hulya Kolbas
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Good Food
By Marion Nestle, March & April 2007
Confused by what a healthy diet looks like? You’re not alone. One of the country’s foremost nutritionists sorts fact from fiction
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For all the hype about wonder foods such as blueberries, broccoli, and almonds, the comforting truth is that all foods have nutrients (except sugars, which have only calories), and depending on which nutrients they contain and how much, all foods have some health benefits. But that doesn't mean you can eat whatever you want and be healthy. Eating too much of certain types of foods and not enough of others may lead to such diet-related illnesses as diabetes, heart disease, stroke, and cancer.
So what is the ideal, health-promoting diet, particularly for someone who's over 50? Fortunately, healthy eating comes down to just a few basic principles. Follow them and you don't need to count calories or carbohydrates or substitute protein shakes for meals or swallow ten different vitamin-and-mineral pills each day. Here's what you need to know:
Less is enough
As you get older, you simply cannot eat as much as you once did without gaining weight. The reason: as you age, your basal metabolism—the energy cost of heartbeats, breathing, and other bodily functions at rest—declines, as does the number of calories expended during physical activity.
While a teenage boy might need 3,000 calories or more every day, he will need just 2,400 per day by the time he's 50 and about 2,200 per day at age 70. An average woman in her 30s needs about 2,400 calories per day, but only 2,100 at age 50 and as few as 1,500 per day when she reaches her 70s.
One way to counter this natural metabolic slowdown is to increase your aerobic activity. Lifting weights also can increase the proportion of muscle to fat tissue, which raises your basal metabolism.
Before you get bummed out at the idea of cutting back on calories, keep in mind we're talking about a moderate decrease, not starvation. It's important not to cut back too much. Despite research showing that lab animals live longer when put on diets with 20 to 40 percent fewer calories, the same may not be true of humans. Starvation is demonstrably unhealthful, and older adults are particularly susceptible to its bad effects. Studies show that people with the lowest rates of disease tend to have body weights at recommended—not extremely low—levels.
Beyond broccoli
You've heard for years that it's important to include plant foods in your diet. Much of the nutrition research we hear about comes from studies of individual fruits, vegetables, whole grains, nuts, and seeds. What researchers have discovered most recently, though, is that plant foods contain literally thousands of nutrients and antioxidants, and eating a variety of them is the only sure way to get all the nutrients you need for health and disease prevention.
Other tips
If fresh fruits and vegetables are unavailable or are too expensive, go for frozen ones; they're almost as nutritious, since they're picked and flash-frozen at harvest, locking in their nutrients. (By contrast, some fresh produce spends weeks in transport, losing nutrients along the way.)
Choose breakfast cereals that have at least 5 grams of fiber per serving, and go for breads that are made with 100 percent whole grains (and that include in the first ingredient the word whole, rather than enriched). This might seem surprising to those of us who remember when the government mandated that breads and cereals be enriched with certain nutrients. But if you're eating whole-grain foods, you'll be getting those vitamins and many more, because they haven't been removed during processing.
Add nuts as garnishes. You don't want to eat too many of them, because they're loaded with calories and fat (even though it's the good, cholesterol-reducing kind). Eating a few, though, is a good thing; they're tasty and can be a powerful source of fiber and heart-healthy nutrients.
The Twinkie menace
Junk is an impolite way to characterize heavily processed foods such as soft drinks, candy, and snacks. If you eat only junk food, you will be taking in lots of calories but few, if any, nutrients. You can probably get away with that when you're younger. As you age, however, this dearth of nutrients can take its toll on your health, increasing the risk for physical and mental disorders and weakening the immune system (thus making the body more susceptible to infections).
Instead, you want to choose foods that are as "natural" as possible. If the ingredient list is long, the food is likely to be highly processed. Shop the grocery store's perimeter, where you'll generally find the most nutritious foods: fresh produce, dairy products, meats, fish, and eggs. The middle aisles carry the most-processed foods, so be cautious and read labels when selecting items there.
An insurance policy
I don't usually recommend supplements for younger people, but I believe that everyone over 50 should consider taking a daily multivitamin. That's because the ability to digest, absorb, and metabolize some nutrients declines with age. Specifically, you are most likely to be deficient in three nutrients—vitamin B12, vitamin D, and calcium.
Vitamin B12 is needed for making red blood cells and for maintaining a healthy nervous system. Its deficiency is characterized by weakness and fatigue, and can lead to cognitive impairment and even dementia among some older adults. Natural sources of vitamin B12 include foods that come from animals—fish, meat, poultry, eggs, milk, and milk products like cheese and yogurt—and while eating lean sources of these foods is important, you should also supplement your B12 intake. That's because up to 30 percent of people over 50—especially those who are ill or taking medications—are unable to absorb the vitamin from food.
Vitamin D is required for calcium absorption and for bone and muscle strength. When we're younger, we easily get enough of the vitamin during exposure to sunlight. But as we age, the ability to absorb the vitamin declines.
Calcium is needed for bone health and may also protect against high blood pressure and colon cancer. You can find calcium primarily in dairy products, though it's also present in small amounts in vegetables, grains, and beans. Some researchers believe you need more calcium than you can get from food.
The risk of these deficiencies can be alleviated by taking a multivitamin. You'll want to choose one that is specifically designed for people over 50 and that contains 100 percent of the Daily Value (DV) for vitamin B12 and vitamin D and at least 10 percent of the DV for calcium. Don't worry about what else it contains.
Do not take supplements of single nutrients in amounts greater than 100 percent of their Daily Values. Excessive amounts of any one nutrient can interfere with the metabolism of others.
Be especially wary of supplements touted as "antiaging" or "life-prolonging." At present there is no such thing as an antiaging pill, though many would have you believe otherwise.
Resveratrol supplements are the latest antiaging fad. This substance, typically found in red wine, keeps mice healthy but only in doses vastly higher than those naturally present in food. Until we know more, you can enjoy a glass or two of wine with dinner, but steer clear of resveratrol supplements.
Drink up
Thirst helps most adults regulate the amount of fluid they need, yet this ability sometimes declines with age. So it's important to drink often, even if you're not thirsty. It is not necessary, however, to drink two quarts of water a day. Food itself contains water. Coffee, tea, juices, and milk all count toward daily fluid intake.
You can monitor your own fluid intake by urine color. If the color is light, you are doing fine. If it is bright yellow and smells bad, you need to be drinking more fluids.
Eating well doesn't have to be difficult. In fact, if you follow these basic principles, you can spend less time worrying about what to eat and more time enjoying your food. Bon appétit!
Marion Nestle is a professor of nutrition at New York University in New York City. Her most recent book is What to Eat
(North Point Press/Farrar, Straus and Giroux, 2006).
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