Preficient is when your nutrient consumption is below the amount for optimal health.
This raises two issues:
1. We don't know the optimal healthy amount for any nutrient
2. We don't measure health scientifically, so we cannot make scientific statements about health optimization.
But we can know many things, and use this information to build healthier bodies, families and communities. Let's start with the basic diagram of deficiency, healthy and excessive nutrient consumption. We'll start with Vitamin A. What do we know about healthy consumption of Vitamin A? Your consumption of Vitamin A might be deficient, healthy, or excessive.
The RDA, or AI - Adequate Intake of Vitamin A, according to the Institute of Medicine (IOM) of the U.S. National Academy of Sciences is 900 ug per day (600 ug for females due to smaller size). The tolerable upper level is 3000 ug per day. Note the IOM advises that these numbers are general - individual results may vary.
So, the optimal amount for optimal health might be somewhere between 900 mg per day, and 3000 mg per day, according to the scientific opinions of the IOM. These numbers are not exact, and have personal individual variations even in healthy individuals. They are designed for use in planning nutrients for healthy people. They are also constantly being researched and debated.
We can update the diagram with these numbers.
The definition of the RDA is such that prolonged deficiency results in a medical condition. The UL is defined where prolonged excess results in symptoms, eg - the IOM does not define the level at which a medical condition will result from excessive Vitamin A.
Somewhere between the RDA and possibly above the UL - is where we will find the optimal nutrient intake level for Vitamin A.
The IOM does not attempt to define an intake level of Vitamin A (or any nutrient) to optimize health - IOM recommendations are specifically designed to avoid illness (deficiency) or symptoms (in excess). There are other sources that do research and provide recommendations for health.
SONA (Suggested Optimum Nutrient Allowance) provides a well researched estimate of the optimal intake of Vitamin A. Their recommendations are summarized in this diagram:
SONA recommends 2000 ug per day for adults to create optimal health. They state that toxicity can appear at 100,000 ug per day in healthy individuals - but caution that lower toxicity levels exist during pregnancy.
Clearly looking from a health view (SONA) provides very different advice than looking from a sickness view (IOM). As we should expect.
But, the title of this blog is "Are You Preficient?" What is 'preficient'? Preficient is pre-deficient. Eg. it is the space between the optimal consumption of Vitamin A and the deficiency (RDA) level of Vitamin A consumption.
You might be preficient, or deficient. If deficient, you might suffer specific illnesses over the long term. If preficient - you will not have optimal health.
When we map the IOM numbers (RDA) and the SONA numbers into a diagram, we can clearly see deficiency and preficiency levels.
What do we know about deficiency? Vitamin A deficiency over long periods of time, causes disease.
What do we know about preficiency? Preficiency is defined as 'the level below optimal health'. Preficiency might cause disease, or contribute to illness - where we have not yet found a link between the preficiency and the illness.
Vitamin A deficiency causes night blindness. Many seniors develop night blindness - which in some cases can be successfully treated with high doses of Vitamin A. Could long term deficiency, or even long term preficiency of Vitamin A cause night blindness? If we simply 'treat' night blindness with high doses of Vitamin A - we simply fix the problem when it is detected. If we act to improve health, instead of simply treating illness - we can avoid the problem before it occurs. We will also be acting to prevent permanent damage caused by Vitamin A preficiency or deficiency.
You might think that no-one, or hardly anyone is deficient.
According to the United States Department of Agriculture USDA's Continuing Survey of Food Intakes by Individuals, 60.1 percent of males over the age of 19 do not consume the RDA of Vitamin A. And 58.7 percent of females as well. Over 25 percent of males and females consumed less than half the RDA of Vitamin A.
Approximately sixty percent of us may be deficient in Vitamin A. Over 25 percent are almost certainly deficient in Vitamin A. However, it is important to note that the Office of Dietary Supplements of the National Institute of Health reports "Vitamin A deficiency rarely occurs in the United States" -- strange? What's going on here?
How many are preficient? We don't know, but we do know it is higher than 60 percent.
Vitamin A is a single nutrient. We know that a majority of adults are preficient of Vitamin A. We can guess that there are many other nutrients that are also preficient. But we don't measure preficiency. And we don't measure health - nor health level changes that might be caused by preficiency.
We should. We might learn, for example, that some specific diseases are caused by combined preficiencies. For example, if an adult is preficient in Vitamin A, and preficient in Omega 3 oils, and deficient in Vitamin B5 - we might find a very specific disease that is directly caused by this combination.
The truth is, we hardly measure deficiencies. And we don't study illness and disease caused by minor, or short term deficiencies. So we cannot take the next step - and measure illness and disease caused by combinations of deficiencies. There are many groups of diseases where our current 'medical paradigm' cannot find the cause. Maybe a health paradigm will help us to find some of these causes.
What can you do? You have only one choice - to do your own research, and make your own decisions. Because even the best information available from the IOM is only valid for 'healthy individuals'. And we don't measure health, so we have no idea how healthy you are - or how healthy I am. You may be able to change your diet to ensure that you consume sufficient quantities of Vitamin A. But if you think you can meet all of your nutritional needs for optimal health through diet - you may want to check out the food myth.
I am not a doctor - I cannot make medical recommendations. But in the case of Vitamin A, there is an easy out. You can consume beta-carotene, which your body uses to create Vitamin A as required. Beta-carotene is benign - it does not appear to be toxic even at extremely high levels of consumption. So you can safely change your diet, or supplement your diet to increase your intake of Beta-carotene, and ensure your Vitamin A consumption is not preficient.
How many other nutrients are essential to optimal health? We don't know for certain. What quantities are required for optimal health? For certain - we don't know.
Yours in health,
Tracy is the author of two book about healthicine: