Everyone knows about the government's Recommended Daily Allowances of
vitamins and minerals, or RDAs. It's impossible not to. They've been around
since 1943 and they appear on everything from cereal boxes to soda cans.
However, RDAs do not represent the nutrient levels needed to promote optimal
health. The National Research Council acknowledged this in 1989 when it
published the 10th edition of Recommended Dietary Allowances.
In 2000, the RDAs are being closely examined and new recommendations are being
made for the first time.
What was wrong with the RDAs?
Well, first a little history. The RDAs were created during World War II. They
were developed largely in response to the malnutrition of the men entering the
army. President Roosevelt signed an executive order: manufacturers were now
required to enrich foods made from wheat, corn, or rice flour with B vitamins
and iron. And at the height of World War II, the Recommended Dietary
Allowances were published. The goal of the RDAs was to estimate nutritional
requirements for preventing basic deficiency diseases. The recommendations were
also meant to be applied as general guidelines for groups, not the gold standard
for individuals.
Research, led by the American Heart Association in the 1960s, has solidly
demonstrated the links between diet and disease. It was already known that
deficiency in certain nutrients results in disease. Studies went on to show
clearly that increased intake of certain nutrients actually helps to prevent
some chronic illnesses. Because of this research and because the RDAs were being
used for purposes other than those for which they were created, new
recommendations were in order.
What are the new guidelines?
The new guidelines are called Dietary Reference Intakes, or DRIs. They are
being developed with individuals in mind. They are also concerned about the
prevention of chronic degenerative diseases, such as macular degeneration, heart
disease, and osteoporosis. The DRIs are based on several factors. These include
the level of a nutrient needed to meet the needs of a healthy individual and the
level at which a nutrient will produce harmful side effects. The DRIs also
consider the source of the nutrient--for example, often the body is better able
to use nutrients supplied in food than by supplements. The new DRIs take age and
gender into consideration as well.
Where can I get information on the DRIs?
Only DRIs for certain nutrients are currently available. The Food and
Nutrition board has published information on the DRIs for calcium, folic acid,
the B vitamins, and related nutrients. Recommendations for antioxidants will be
available soon as well. You can receive information from the National Academy
Press (call 888-624-8373 or visit their Web site at www.nap.edu).
The FDA will not require manufacturers to change food and supplement labels
to reflect the new levels until DRIs have been established for all nutrients.
All DRIs are expected to be determined within 1 to 2 years.
The bottom line
All in all, the new DRIs are much better standards for people wanting to know
what is needed for optimal health. However, it's important to note that the DRIs
do not consider environmental factors (for example, city smog) or lifestyle
choices (such as smoking) that can destroy nutrients. They also do not reflect
the nutrient levels that may be helpful in combating serious disease.
