Perhaps what's more important than what they represent - a continuous attempt to assess our nutritional needs - is the fact that they're not working.
Perhaps what’s more important than what they represent - a continuous attempt to assess our nutritional needs - is the fact that they’re not working.
What’s the Difference?
In simple terms, “RDAs” stands for Recommended Dietary Allowances, or the amounts of certain nutrients people are urged to consume daily. The US-based Food and Nutrition Board of the National Research Council originally established RDAs in 1941. Nutritionists, governments, and nongovernmental organizations have used them as a broad basis for food and nutrition recommendations.
For a while, Canada’s equivalent to US RDAs was the Recommended Nutrient Intakes (RNIs). Used for similar purposes, and formulated in a similar matter, both sets of values were replaced in 1997 by Dietary Reference Intakes (DRIs), which is an umbrella term that now describes four types of reference values. The new guidelines provide minimum, maximum, and optimal nutrient levels.
Confusingly, one of these four values is, again, called RDAs, which Health Canada now defines as “the average dietary intake level that is sufficient to meet the nutrient requirement of nearly all healthy individuals in a particular life-stage and gender group.” Yet many natural health experts argue that the suggested nutrient amounts are so low they do little to protect Canadians from current health threats.
“You simply cannot get the optimal levels of some key vitamins and minerals if you eat according to the RDAs,” states Dr. Nigma Sciortino of the West Vancouver Naturopathic Clinic. She explains that the RDAs were first developed to prevent deficiency-related diseases, such as scurvy (lack of vitamin C) and pellagra (lack of niacin). However, there’s a definite difference between eating to prevent a deficiency and eating for optimal wellness.
A major criticism of the RDAs is that they do not take into account individual needs. RDAs represent a general set of dietary guidelines for large groups of people. They don’t consider environmental and lifestyle factors that affect our nutritional status. Smoking, for example, depletes vitamin C, which is why many physicians recommend smokers take vitamin C supplements. In contrast, the RDA for vitamin C is 60 mg daily, not nearly high enough to counteract nutrient loss from smoking.
And what about increased nutrient needs during stress or illness? Nobel Prize winner Linus Pauling recommended two to nine grams of vitamin C in these circumstances. Although food remains the ideal way to receive nutrients, naturopathic physicians commonly recommend extra vitamin C for optimal health and to provide antioxidant protection against disease.
“Where RDAs really become inadequate is for the elderly population, who are usually chronically dependent on drugs,” says Dr. Sciortino. Prescription drugs interfere with the body’s nutrient absorption. Statistics show 75 percent of Canadians 65 and older living in a private home take prescription or nonprescription drugs on a daily basis. When institutionalized, that percentage jumps to 96 percent of seniors.
Still other lifestyle and environmental factors either deplete the body of nutrients or require a higher nutritional intake than provided by RDAs, including alcohol use, food additives, heavy metals, and exposure to environmental pollution.
The end result, says Dr. Sciortino, is a population suffering from chronic malnutrition. “While Canadians have enough of a calorie-rich diet, we are robbed of essential nutrients that keep our bodies healthy and strong,” she says, adding it can take 10 to 20 years for effects of poor nutrition to be revealed, most likely in the form of preventable and chronic diseases such as cancer, diabetes, stroke, and heart attack.
Since the RDA dietary guidelines aren’t enough, additional measures are called for in the form of health supplements. “Study after study from some of the most prestigious universities have advocated the need for nutritional supplements as effective ‘cheap health insurance’ for a long and healthy life,” says Dr. Sciortino.
In her practice, she recommends patients take a high-quality multivitamin/mineral supplement, plus extra antioxidants. She suggests taking 1,000 to 2,000 mg of vitamin C with bioflavonoids daily.
Although not considered vitamins, omega 3s, 6s, and 9s, also known as essential fatty acids (EFAs), are vital to the body. Dr. Sciortino frequently sees patients who are EFA-deficient, typified by dry skin and immune suppression. She recommends one tablespoon (15 mL) of an essential fatty acid oil blend per 50 pounds of body weight, which means a 150-pound person would take three tablespoons (45 mL) daily.
She cautions that people need their own health analysis from a naturopath or other health practitioner. Blanket-style supplementation, like the RDAs, can fall short of the mark when compared to a more individualized nutrient program.