Requirements for Vitamins A and C Disputed : Revised Recommended Dietary Allowance Figures Won’t Be Released
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.
“It was the 40th anniversary of the RDAs, and the 10th edition,” he said. “We were told to take a fresh start--not to depend on the old RDAs.
“Our committee did just that. We went back to origins, worked harder than any other committee and finally came up with a first draft, which went out to the anonymous reviewers (which is part of the procedure of the academy). The reviewers had many comments and many constructive suggestions. We responded to these and this took us to July. Then we got another letter on the residual issues involving several nutrients--including vitamins A and C--and some distress expressed that there were too many changes.
“In my response to those reviewers I stated that it is not wise in science to simply continue old data because there is nothing wrong with it. We are supposed to give the best advice possible.
“At that point, I got a verbal reply that my defense was valid, and as far as I knew that ended the issue. The next major communication was a letter to me from Dr. Frank Press, chairman of the National Research Council, stating that all major issues have been resolved except those on vitamins A and C.
“I offered to send further scientific information to justify our solution. I asked a number of times for scientific criticism of vitamins A and C and never received them. I had no further communication at all from the academy until Oct. 7 when Dr. Press notified me that they were rejecting the report and the reasons were outlined in a five-page letter to (Dr. James) Wyngaarden, who is the director of the National Institute of Health, which funded the study for $1.5 million.
“The letter to Wyngaarden contains no mention at all of vitamins A and C, but deals with issues of excessive, unnecessary changes.”
Reasons for the Rejection
Kamin said he was miffed by the lack of concrete reasons for rejection.
“This led me to think that they might not have even read the document . . . and that there is enormous confusion and incompetence at the National Academy of Sciences.
“In reality, the report is being rejected, despite what Dr. Press says, on the narrow ground that they did not want our numbers of A and C and preferred the old numbers (1980 allowances). But they gave no scientific reason for the preference. In absence of scientific criticism for our results, despite our offers to open scientific discussions and requests for scientific justification, the rejection could only stem from the desire on the part of the academy to avoid controversy,” Kamin said.
Palmer of the National Research Council denied any political involvement in the academy decision. “The reason for not issuing a report is scientific. The academy has nothing to gain or lose. We’re a scientific organization, not a political one,” she said.
Kamin accused the academy of bowing to pressures from the Food Research and Action Center, a nonprofit public-interest advocacy organization.
He also pointed a finger at the Cancer Research Institute, which has in recent years credited carotenoids, found in carrots and other vegetables high in Vitamin A content, as a protective agent in cancer for succumbing to political maneuverings.
“In Washington, D.C., there has developed a climate of nutritional activism,” Kamin said. “If, for instance, you have the barest hints of something that has an effect on something, you should start a public program to push it.”
As for the Food Research and Action Center, its director, Michael Lemov, said that a letter was written to the National Academy of Sciences urging that the allowances not be reduced and that the academy consider appointing a new committee. “We’re very happy that Dr. Press considered our argument and decided to keep the RDAs at status quo,” he said.
“FRAC took issue with reductions in RDAs, not only because there was no scientific development since 1980 to warrant a reduction of the RDAs, but, more to the point, a reduction in the RDAs would likely cause a downward revision in amounts of food people would receive under the food school lunch and elderly food programs,” Lemov said.
“We have the corroboration of key people on food programs that (our recommendations) will have no effect on food programs,” Kamin said. “If scientists begin to twist science to please policy makers or constituencies, you are going to end up with lousy science and lousy policy. Science should have no choice but to exercise (no other) option except to give the best advice possible and nothing less.
“Unfortunately, the Food and Nutrition Board has gradually acquired an increased proportion of activists and a decreased proportion of cold-eyed, skeptical scientists.”
Unfortunate Outcome
Meanwhile, the American Dietetic Assn., whose membership of dietitians constitutes a major group affected by the release of the allowances, thinks the outcome of the allowances is unfortunate but not hopeless.
“This is an unfortunate situation because it has led to more confusion in terms of guidance in nutrition matters for the American public,” said Anita Owen, president of the association. “That’s the negative side. On the positive side, I think the National Academy of Sciences now has an opportunity to look at the RDA process as it stands and make some changes that will make room for users of the RDA and scientists to participate in the process, as well.”
Owen also said that although it would have been nice to have the new data, dietitians still have the 1980 allowances, which have served well in the past five years and are adequate and relevant.
Other nutritionists and dietitians voiced some concern about the allowances in relation to food programs.
“So many food programs are pegged to the RDAs and only that. Obviously, money is involved, so if you lower the RDAs you lower the quality of food intake and make up the calories from less-expensive sources. Money is an overriding factor on the economic side of the picture,” said registered dietitian Rita Storey, media representative for the California Dietetic Assn. “I am not saying it’s good or bad, but I can sympathize with the activist groups because they know that the dollar dictates what goes on in programs.”
Storey said that she was surprised that the Cancer Research Institute’s recent acknowledgement of carotenoids as a protective agent against cancer did not carry more weight in the committee’s overall accessment.
(The American Cancer Society has not issued an opinion on the non-release of the allowances.)
Genevieve Ho, nutritionist at the Agricultural Extension Service, said the allowances will not greatly affect the public. “They are a ballpark figure, not something we have to go on literally. Americans will find the Dietary Guidelines for Americans, which call for eating a variety of foods from the four food groups, far more flexible. The RDAs are meant as a yardstick with plenty of room to move around it. Besides, people can go by the old RDAs until there is more consensus among the scientists,” Ho said.
Lynn Parker, nutritionist at the Food Research Action Center, indicated that her concerns had to do with the philosophy behind the committee’s allowances. “The RDAs were changing from optimal health to an emphasis on minimum nutritional standards. Another concern had to do with the reduction of actual nutritional values.”
“I think it was a case of nutritional biochemists looking at issues from minimum levels of nutritional deficiencies,” Parker said. “They probably were not aware that the RDAs are the basis of poverty-level programs. Our feeling is that there is so much uncertainty in science, that when you come up with values based on limited data, it’s always better to err on the side of caution.”
Uncertain Future
What happens now? Will there be a report on the allowances?
Kamin would like the academy to reconsider the committee’s report. “I have always been willing to renegotiate and re-examine all on the basis of nutritional argument. I made an offer and will continue to make offers for resolving the scientific issues of A and C. That remains open and for the academy to fulfill its contract, while defending scientific honesty and prevent science from being contaminated by political pressures.
“All the science in our report remains subject to scientific discussion, but it is not subject to change because of public pressure. If the academy recognizes this and doesn’t make the mistake of drifting away from science to hypersensitivity to public pressure, the matter can be resolved. The ball is in their court.”
But hope for any resolution with the old committee seems nil.
According to National Research Council’s Palmer, because scientific differences were not resolved, the academy will put together a new committee within a six months to address the reviewers’ concerns. Meanwhile, the 1980 allowances will stand.
