RDA guidelines for Nutrients

May 24, 2022

Many of you probably associate the RDA abbreviation from dietary supplement packaging.

It stands for 'recommended daily allowance' – “are the levels of intake of essential nutrients that, on the basis of scientific knowledge, are judged by the Food and Nutrition Board to be adequate to meet the known nutrient needs of practically all healthy persons”.

For example, the recommended daily intake of vitamin D for adult man and woman aged between 19 and 50 is 15mcg (600IU)

But what does this mean in reality?

RDA, translates to a dose that covers the need for 97.5% of healthy, properly nourished people.

I did not accidentally underline a piece of this sentence. These recommendations are calculated for healthy people, without nutrients deficits, meanwhile the general health of today’s society is not optimal therefore the RDA standard actually applies to a small part of the society.

Last year’s report on vitamin D deficiencies in Ireland shows that as many as 47% of men and women aged 18-39 have the deficiencies. At the same time according to hse.ie 60% of adults and over one in five children and young people are overweight or obese.

These factors increase the demand for supplemented nutritional intake, which in-line with the reality of society would help support reduction in other illnesses and disorders.

In addition, the RDA value is usually calculated based on the study of a relatively small number of healthy people and determines the recommended level of consumption of 2 standard deviations above average daily demand. In many cases the demand is significantly greater than the average recommended demand, considering the large biochemical diversity of the human population, which is also confirmed by dose dependent research.

It is estimated that there is only about 30-40% of the chance that you will cover your real requirement for nutrients, if you consume them as per the RDA guidelines, couple this with any underlying health conditions, genetic traits, and other sociological factors it’s clear that the reduction in all cause mortality is highly supported in populations which supplement need.

RDA standards probably also do not apply to people prone to develop diseases and among disease predisposing factors we can name:

Excess stress
Exposure to environmental toxins that occur in their work environment
Sleep deficiency etc

Keeping that in mind, people whom have any ongoing health concerns or confirmed abnormal blood work are likely to require higher than standard recommended doses of nutrients.

It is worth considering if you are fit and healthy but also training, building and recovering as part of an exercise routine you are more likely to require a higher RDA than mentioned as standard.

At the beginning of this article I mentioned that the RDA for vitamin D for adults between 19 and 50 years old is 15mcg (600IU) but because of the common deficiencies the recommendation for Irish population is now much higher:

Daily Vitamin D supplements of 20-25µg/day (800–1000 IU/day) should be

appropriate, as a public health measure to reduce the risk of respiratory and other

illnesses such as osteoporosis. The Committee recommends that where required, any

supplementation at higher doses than this should be taken under medical supervision.

Conclusions:

1. Even if we are fully healthy, the recommended daily intake protects us against nutrient deficiency, but this is not mean the protection against chronic diseases.

2. If we are not fully healthy, the mere fact that we meet official standards does not mean that we will not need larger amounts of different nutrients.

3. If we are chronically ill, we have a diagnosed disease, then we have almost a guarantee that our body needs more, sometimes much more necessary nutrients than as per the norms.