Good nutrition is important throughout life, but it takes on special significance in middle age and beyond.
"All the nutritional things that we need to be concerned about as younger adults are even more important as we get older," says Alice Lichtenstein, a professor of nutrition at Tufts University.
That's because starting in middle age, the body begins losing about 1 percent of muscle per year. Fat replaces the lost muscle. Since fat cells need fewer calories than muscle cells to survive, metabolism slowly declines.
Add to that the inactivity that often occurs with aging, and you need to eat fewer calories — or risk expanding with age.
What makes it even trickier is that the requirements for essential vitamins and minerals stay the same or increase with age. It takes wise food choices to avoid falling short on nutrients that control blood pressure and promote heart health, digestion, immunity and blood clotting.
To help provide guidance for older adults, Lichtenstein and her colleagues at Tufts have crafted a modified food pyramid for those age 70 and older.
First published in 1999, it has just been updated to reflect the latest nutritional advice for seniors. But its messages are good for all ages and are meant to be used in conjunction with the U.S. Department of Agriculture's Food Pyramid, which this month launched My Pyramid Menu Planner, an interactive tool to help make smart food choices easier.
The foundation of the pyramid for older adults is physical activity. There's clear evidence that staying active delays moderate to severe physical changes that begin in middle age and continue into older years. But even for those who have been sedentary, the latest research suggests that it's never too late to start moving more.
"Older adults can improve physiologic capacity — aerobic, strength and balance — with targeted exercise at any age," Miriam Nelson, another Tufts researcher in nutrition and exercise, recently reported to the Physical Activity Guidelines Advisory Committee. (The Health and Human Services Department convened the committee to write the nation's first set of physical activity guidelines, which are slated to be issued later this year.)
The recommendations for older adults highlight the importance of so-called lifestyle exercises, such as walking the stairs, doing yard work and housecleaning.
"You don't have to join a gym," said Lichtenstein, who keeps her washer and dryer in the basement so that she walks the stairs to do the laundry. "One day," she says, "I plan to calculate how many steps I've taken to do the laundry in the 19 years since we moved into this house."
For the special nutritional needs of advancing age, it's important to eat foods rich in calcium, potassium and vitamins D, E and K. Government-sponsored food surveys show these are most likely to be the shortfall nutrients for older adults.
The modified pyramid urges consumption of whole grains and beans, which are both rich in fiber. It also advises eating more bright-colored vegetables, such as carrots (rich in beta carotene, which is converted to vitamin A by the body) and broccoli. (Like cabbage and Brussels sprouts, broccoli is a cruciferous vegetable that can help reduce the risk of cancer.)
And the pyramid recommends consuming more deep-colored fruit such as blueberries and strawberries, which have a range of healthful nutrients including vitamin C and folate, a B vitamin.
The pyramid urges older adults to consider frozen as well as canned fruit and vegetables, which have a longer shelf life and require no peeling or cutting — a factor for those who have arthritis in their hands. Frozen and canned items are often economical, too, another consideration for those on fixed incomes.
The pyramid for seniors also emphasizes eating plenty of low-fat and nonfat dairy products as well as calcium-fortified juice and cereal to help boost intake of calcium, a key mineral that helps maintain healthy bones, hearts and blood pressure.
And the pyramid urges drinking plenty of fluids, especially water. Aging lessens the sensation of thirst. So older adults should consciously plan to drink enough, rather than just waiting to feel thirsty. Current recommendations from the Institute of Medicine are 12 cups of water per day from beverages and food for women 70 and older, 16 cups for men the same age.
At the same time, too much sodium is a concern. Adequate intake is 1,300 milligrams per day for people ages 51 to 70 and 1,200 for those 71 and older. That's about 1,000 fewer milligrams than what most seniors consume, according to government surveys.
So take note, boomers: Each hour, 300 more boomers turn 60, according to the Census Bureau. In about a decade, they'll be ready for that modified food pyramid for older adults, so it's not too soon to start making changes now.