June 10, 2004 -- The ancient mariners had scurvy. Andapparently, plenty of Americans today have it, too. We're not getting enoughvitamin C, the main preventative for scurvy or vitamin C deficiency,researchers say. Could low-carb eating be to blame?

The report appears in the current issue of the AmericanJournal of Public Health.

It provides results from a large nationwide survey, showingthat seniors and children get the most vitamin C in their diet. However, menand women aged 25 to 44 get the least -- and are most at risk for developingscurvy.

"A considerable number of U.S. residents are vitamin Cdeficient," writes researcher Carol Johnston, a professor of nutrition atArizona State University.

Other studies have shown similar results, she writes. One U.S.study shows that 18% of adults get fewer than 30 milligrams daily of vitamin C.Another study shows that up to 20% of the 13- to 18-year-old group gets fewerthan 30 milligrams daily.

Because scurvy is rarely suspected, people with the symptoms --fatigue, limping, bleeding gums, or swollen extremities -- may not be testedfor vitamin C deficiency, she explains. Very often, these patients aremisdiagnosed and medicated for other disorders -- not for their vitamindeficiency.

The recommended daily allowance for vitamin C is 75 milligramsfor women and 90 milligrams for men. While some people get too much vitamin Cin their diets, many others get too little, she says. The body excretes excessvitamin C in the urine.

With the low-carb craze, the vitamin C-rich potato -- once thecenterpiece of a healthy diet -- has been pushed aside, notes Althea Zanecosky,MS, RD, a spokeswoman for the American Dietetic Association and professor ofsports and nutrition at Drexel University in Philadelphia. She agreed tocomment on Johnston's study.

"Potatoes are a great source of vitamin C and othernutrients," Zanecosky tells WebMD. Other vitamin C-rich fruits are alsotaboo for some people adopting a low-carb diet.

The Study Details

In her study, Johnston used data from health and diet surveyscompleted by 15,769 Americans aged 12 to 74. Each person surveyed also had hisor her blood tested for vitamin C levels.

Among her findings:

• 14% of males and 10% of females were vitamin C deficient.
• Only 6% of 12- to 17-year-olds were deficient.
• The adults aged 25 to 44 had the worst vitamin C levels.

Nearly one-quarter -- 23% -- of males aged 25 to 44 werevitamin C deficient, compared with 15% of 65- to 74-year-olds.

Among females, 20% of those aged 25 to 44 were deficient,whereas 13% of 65- to 74-year-olds were also vitamin C deficient.

Also:

• Smokers were nearly four times as likely to be vitamin C deficient asnonsmokers.
• Those who didn't take a vitamin supplement were three times as likely to bedeficient in vitamin C.