Federally Recommended Daily Allowances Being Updated

When nutritionist Jayme Kukowski talks to clients about an everyday eating plan, she doesn’t rely on the government’s Recommended Daily Allowances, or RDAs.

“Research in the last five years has outdated the RDAs,” Kukowski said. “I usually only talk about RDAs to point out people should be consuming more than the recommended amounts.

“For example, the RDA for vitamin C is 60 milligrams. I suggest 500 milligrams. I know doctors and nutritionists who routinely advise 1,000 milligrams. It’s a proven antioxidant that helps protect against cancer and heart disease.”

The RDAs for vitamins and minerals, which were last updated in 1989, are intended to prevent deficiencies that lead to disease (such as scurvy, in the case of vitamin C). They aren’t necessarily aimed at promoting optimum health.

That doesn’t mean experts are advising megadoses of every conceivable nutrient or food component. It’s possible to overdo it, especially on fat-soluble substances that the body stores instead of flushing out. The body also can convert excessive amounts of such touted antioxidants as vitamin C or E or beta carotene into “pro-oxidants,” which can wreak havoc by introducing too many free radicals, or wayward oxygen cells, that attack healthy molecules.

Dietitians like Kukowski are left to determine what amounts are effective yet safe, whether the nutrients are gained from food or supplements.

“You want to eat a balanced diet for most of your nutrients,” Kukowski said. “Some supplements make sense. Depending on dietary choices, some women might do well to take calcium and iron. Men should avoid iron, but they might not get enough vitamin E or C.”

Federal administrators recognize the gap between RDAs and reality. The Food and Nutrition Board of the National Academy of Sciences is developing new recommendations called Dietary Reference Intakes, or DRIs, for vitamins, minerals and several phytochemicals that show potential for reducing chronic disease.

The plan calls for new RDAs plus an additional category called “upper intake levels,” or ULs, to guide people on maximum amounts. Nutrients will be studied in groups, and the revised RDAs and ULs will be announced in stages through 2000.

“This current review will be much more extensive than what we’ve done in the past,” said Janet King, director of the U.S. Department of Agriculture’s Western Human Nutrition Research Center in San Francisco and member of the central DRI committee.

“We will be looking closely at the research literature for components of food like choline, lecithin and beta carotene to decide whether we need to set standards for dietary intake of these substances, even though they haven’t been identified as essential for life. These substances do appear to be important for maintenance of health.”

The first new numbers, expected in August, will focus on nutrients related to bone health, including calcium, vitamin D, phosphorus, magnesium and fluoride. A review committee is evaluating folate and other B vitamins, with recommendations due in April 1998.

Five more groups will be studied in the coming months: antioxidants (vitamin C and E, beta carotene, selenium); macronutrients (protein, fat, carbohydrates); trace elements (iron, zinc, etc.); electrolytes (sodium, potassium) and water; and other food components (such as fiber and phytoestrogens).

“There are a lot of (supplement) products with doses that are not proven for health or safety,” said Tracy Fox, a registered dietitian with the American Dietetic Association’s government affairs division in Washington, D.C.

The new recommendations should make it easier for customers to assess manufacturers’ claims.

The ULs will be a bonus for dietitians working with clients who tend to think “more is always better,” Fox said. A more realistic set of RDAs is a solid first step.

“The ADA likes anything that promotes health,” Fox said. “The next key element is effectively sending the message to consumers.”

This task is formidable during a time when even the experts admit to an overload of nutrition information, some of which can be contradictory. A unified effort from federal authorities and dietitians would help keep the message simple for the rest of us.

“The government has been under-recommending nutrients for years,” Kukowski said. “It’s great to see there is willingness to correct that.”