We live in an aging nation, where the elderly are the fastest growing segment of our society. And we’re not alone.

Globally the number of people over 60 is expected to triple by 2050, according to a recent United Nations study.

“We have a lot of issues to tackle related to an aging society and a retired society,” said Mary Ann Johnson, a foods and nutrition professor at the University of Georgia. “We have to figure out how to afford it financially, how to help people live enriching lives and how to encourage better physical and mental function in older people.”

For her part, Johnson studies the foods and nutrients that help delay or prevent age-related diseases in older adults: osteoporosis, hearing loss, obesity, diabetes and anemia, to name a few.

For more than 14 years, she has tracked the nutritional status of more than 2,000 Georgians participating in the federally funded Elderly Nutrition Program, more widely known as Meals on Wheels and Congregate Meals. Her team studies nutrition in this group and develops educational programs that promote exercise and good nutrition.

“In collaboration with the Centers for Disease Control, we measured several vitamins in the blood that are good markers of peoples’ nutritional status — vitamin B-12, vitamin D and some others. We found a very high prevalence of vitamin B-12 deficiency, almost three times as high as the national norm,” said Johnson who published these findings in the January 2003 issue of the American Journal of Clinical Nutrition.

Vitamin B-12 occurs naturally in foods like meat, fish, poultry and dairy products. But some 30 percent of older adults can’t make enough stomach acid to digest B-12 from food.

The result is that many older people can’t get enough B-12 no matter how much they eat, according to Sally Stabler, a physician and associate professor of medicine at the University of Colorado Health Sciences Center School of Medicine in Denver and one of Johnson’s collaborators. Vitamin B-12 deficiency is associated with anemia and some vascular diseases.

“We also see relationships between someone’s vitamin status and their hearing level and between vitamin status and cognition,” Johnson said.

Johnson found it’s easy to raise B-12 levels in the blood and even correct deficiencies in older adults by giving them vitamin pills. However, in ongoing studies she and other researchers find that while reversing the B-12 deficiency was rapid, the effect on hearing and cognition was disappointing.

“Giving the B-12 back does not restore function,” Johnson said, “and that’s not too surprising. Part of the underlying pathology of B-12 deficiency is nerve damage and nerves are very slow to heal.”

Deficiencies in vitamin D and calcium, its partner in metabolism, are also a widespread problem in older adults. Major sources of vitamin D are sunshine and fortified milk. But older adults have a hard time getting enough of the vitamin, Johnson said, because:

• their skin doesn’t make vitamin D as efficiently;
• they may not get outside enough;
• wearing sunscreen blocks the light that makes the vitamin in the skin;
• they may be lactose intolerant and not drink milk; and
• a person over 70 needs three times as much vitamin D as a young child.

“About 10 percent of older adults are D-deficient to the point they have a bone disorder called osteomalacia,” Johnson said. “Another 30 percent are in the marginal range.”

Based on her nutrition studies in older Americans, Johnson’s team has developed a variety of educational programs including one on nutrition and bone health to address the vitamin D problem.

“My research and outreach feed back and forth on each other to help promote nutrition, health, and wellness in older adults.” Johnson said.

For more information, contact Mary Ann Johnson at
mjohnson@ fcs.uga.edu.