Revised Recommended Dietary Allowance figures, the nutritional vitamin and mineral yardsticks on which a healthful diet is based, will not be released as expected now or in the near future. Changes from the latest review of the figures, made in 1980, originally were slated for release this past summer.
In August, Helen Guthrie, a Penn State University nutrition professor and a member of the Dietary Allowances Committee appointed by the Food and Nutrition Board of the National Research Council, announced that the release of the new RDAs would be postponed a month.
There would be some changes from the 1980 allowances, she told dietitians and nutritionists attending the first session of the Society for Nutrition Education's annual meeting at the Bonaventure Hotel. The changes, she said, would be in the age and sex categories for infants, adolescents and elderly, as well as some minor modifications for certain vitamins and minerals.
But then something strange happened.
The new RDAs never were released.
There was buzzing among nutrition circles that the National Research Council, which is organized by the National Academy of Sciences, could not agree on certain nutrient changes recommended by the committee.
Provide a Yardstick
The RDAs were established after World War II to provide a national yardstick for levels of nutrients considered desirable for almost every healthy American. They also have been a basis for federal and state food product labeling laws and food programs in prisons, schools and government hospitals and for the elderly. The allowances are also the nutritional bible for dietitians and other practitioners who work in hospitals, institutions and the food industry.
In reviewing the new changes, the academy rejected the committee's recommendation on the lowering of two essential vitamins--A and C. "We were unable to resolve scientific differences," stated Sushma Palmer, executive director of the Food and Nutrition Board of the National Research Council, which is organized by the National Academy of Sciences.
Guthrie explained: "Basically, we submitted our report to the National Academy of Sciences. They had some recommendations, and the anonymous review committee had some recommendations for modification. We agreed on everything but vitamins A and C. We simply couldn't reach agreement on these two nutrients or they did not accept our compromise. So they decided not to publish anything at all.
"I think it is unfortunate that there wasn't more of an effort to resolve the compromise. The major problem is that practitioners are not going to have the benefit of the thinking of the committee, who worked hard over the last five years."
But Henry Kamin, professor of biochemistry at Duke University, who served as chairman of the Dietary Allowances Committee, saw more to the disagreement over two vitamins than met the eye.
"If you ask me," he said, "the real issue is not with A and C. The changes we have proposed are much closer to the 1974 RDAs and in keeping with the RDAs of other nations. Fear is the controversy. The academy rejected the report because they feared controversy. They panicked. The whole thing is bizarre and represents a misunderstanding and a collapse to social pressures. The issues are not issues of science."
The 1974 recommendation for Vitamin C was 45 milligrams; for Vitamin A, 5,000 international units for men and 4,000 for women. The 1980 allowances raised Vitamin C recommendations to 60 milligrams, but the Vitamin A recommendations remained the same.
'Assumptions No Longer Valid'
James Olson, professor of biochemistry and biophysics at the University of Iowa who was vice chairman of the Dietary Recommendations Committee, and whose specialty is Vitamin A as well as vitamins E, D and K, said that the new numbers for vitamins A and C agreed "much better" with nutritional allowances worldwide.
"The scientific basis for lowering the vitamins is that previous recommendations were based on certain assumptions we no longer feel are valid," he said. "The new recommendations agreed better with the median intake of Vitamin A in the United Sates, the World Health Organization and many countries in the world, and we don't feel there is any real reason for having the number any higher than we developed. The argument is very much the same for Vitamin C."
Olson also said the recommendations for vitamins A and C have been decreased "purely" on scientific evidence. "We have not included concerns of policy implications, the main reason being that we feel that scientists should deal only with things they know something about. As a second step, policy makers could deal with them (recommendations) and modify them as they see fit. But we can't mix them together and have a basis for science and nutrition."
According to Kamin, the dietary committee document was prepared under the guiding directive of the Food and Nutrition Board of the National Academy of Sciences issued in 1980.