Healthful diet, hidden deficiency: are you getting enough [B.sub.12]?

Most North Americans associate serious vitamin deficiencies with third world countries or extreme poverty, not with their own comfortable lifestyles--and certainly not with low-fat, low-cholesterol, high-fiber diets brimming with whole grains, dried legumes, brown rice, rolled oats, fresh fruits and daily helpings of dark green, leafy vegetables.

But such a diet, although high in health-promoting folate, is also low in vitamin [B.sub.12], a substance found naturally only in meat, fish, shellfish, eggs, milk or dairy products. It's tree that our bodies require only a small amount--about 2 micrograms (mcg)--of [B.sub.12] per day. But if you think your body could skip this miniscule intake without consequence, think again.

A [B.sub.12] deficiency can result in symptoms ranging from severe anemia to serious and possibly permanent nerve damage and cognitive impairment. Left untreated, it can cause increasingly abnormal blood cell division, leading to lymph cancer and death. And while most vegans know they're at high risk of [B.sub.12] deficiency unless they take supplements or eat fortified foods, this hidden health risk blindsides many people who least suspect it.

Better with Age?

As we age, our bodies lose some ability to absorb vitamin [B.sub.12] and may cease absorption altogether. Richard Woodman, MD, a hematologist in the department of medicine at the University, of Calgary, Health Sciences Centre in Alberta, estimates that up to 30 percent or people aged 50 and over are affected to some degree. This puts even those with diets high in animal products at increasing risk of deficiency from midlife on. "After 65, about one in 20 North Americans is clinically deficient in vitamin [B.sub.12]," he says, "but borderline deficiencies are probably much higher and affect a significant percentage of older people."

More dangerously, a high-folate, low-[B.sub.12] diet masks fire first clinical signs of [B.sub.12] deficiency and delays diagnosis, allowing progressive nerve damage to continue unabated for as long as 5 years.

Cathy Thornton found this out the hard way. At 54, she and her husband, Jim, 56, attributed their good health and abundant energy to daily exercise and their 29-year vegetarian diet that included dairy products and eggs. But there came a time when Cathy began to feel anything but energetic.