It is so strange, in an era of overly processed foods and refined sugars, nutritionists continue to maintain the American diet is sufficient to meet the nutrient needs of Americans. This drivel continues despite the fact recent studies do not confirm the consumption of fruits and vegetables significantly reduces mortality rates for heart disease and cancer, the number one and two chronic diseases that drive mortality rates. Even the 9-13 servings of plant foods-regimen now recommended by health authorities still is an unproven measure.
If you are totally confused by the array of acronyms RDA (Recommended Daily Allowance), RDI (Reference Dietary Intake), AI (Adequate Intake), EAR (Estimated Average Requirement) and DV (Daily Value) used to inform Americans how much nutrition they need, join the crowd. For various reasons, all of these should be disregarded, as explained below.
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Diet + Supplements
One of the problems in reading charts which describe how much of each essential vitamin and mineral is needed in the diet is that consumers don’t recognize that these numbers represent diet plus supplements. So, for example, the Recommended Daily Allowance (RDA) for calcium is 1000 milligrams (mg) and the typical American diet provides ~946 mg, so calcium supplements are not needed.
But menopausal women hear that they need 1200 mg or 1500 mg of calcium to maintain bone and opt to purchase bone mineral supplements which provide the entire 1200 mg daily requirement on top of what the diet already provides. If calcium is being lost from bone due to the loss of estrogen production in the ovaries, then correction of this problem lies in replacement of the estrogen, not more calcium. Otherwise, the more calcium that is consumed in post-menopause the more calcium that is deposited from bones to arteries. This is why calcium supplementation has recently been linked with stiffening of arteries and mortality from coronary heart disease. Frankly, while calcium is one of the top food supplements sold today next to multivitamins, fish oil and vitamin C, it may be a nutrient that needs to be axed from the daily supplement regimen of many Americans. Americans live in a dairy country and obtain sufficient calcium from the diet. 20512078
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Bottom line, read the RDA, RDI, etc, charts with knowledge that they represent what you need from diet plus food supplements. The chart provided in this article more accurately helps to distinguish the contribution diet and supplements make towards meeting nutrient needs.
Nutrition Requirement Charts May Not Apply To You
Another factor the nutrition charts don’t address is who you are. Let’s take a look at iron in the chart below. The diet provides around 14.7 mg per day of iron and supplements add, on average, another 3.0 milligrams, for a total of 17.7 mg of iron from diet plus supplements for the average American who take supplements. But when data on intake levels for supplement users alone is singled out, supplement users may be getting over 36 milligrams of iron per day! That much iron could be tolerated by a growing child who needs to make millions of new red blood cells per second, but maybe not for full-grown males who have no outlet for excess iron and accumulate it in their organs and tissues. Supplemental iron may be beneficial for menstruating females who control their iron via their monthly blood flow, but maybe not post-menopausal females who are in the same situation as full-grown males. This iron gets stored in compartments in the body, particularly in the liver where it can cause a fatty liver condition that affects around 35% of American adults. Sweden abandoned iron fortification in foods when it realized fatty liver was an unwanted consequence. Supplement users could be getting a figurative truck-load of rusty iron and copper and artery-stiffening, kidney-accumulating calcium. Eugene Weinberg, researcher at University of Indiana, even goes so far as to suggest iron fortification in foods should be abandoned.
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Do supplement users commonly overdose?
While the following chart may make it appear supplement users overload on certain nutrients – that is far from the truth. A primary reason is that the RDA is only designed to meet the nutrient needs of healthy individuals. The RDA is supposed to meet the nutrient needs of 98% of the population, but does it really do that? There are so many millions of Americans who take nutrient-depleting drugs, who are under physical or emotional stress that depletes B vitamins, who smoke tobacco that depletes vitamin C, who have chronic illness (like diabetes) that increases nutrient demand, who don’t go outdoors during midday and receive sufficient amounts of sunlight to produce vitamin D, who are of advanced age and don’t produce sufficient levels of stomach acid to properly absorb nutrients, that one wonders if the RDA is even relevant in today’s society. It’s as if nutrient deficiencies are being programmed in by intentionally limiting specific nutrients from the diet.
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RDA level is not optimal health level
Another problem with the RDA is that it is designed to provide the minimum amount of nutrients needed to avert a deficiency disease, not the optimal amount for health. And the RDA certainly doesn’t apply to growing children for females during pregnancy who have acute nutrient demands.
RDA is outdated
Also, the RDA has not kept up with changing dietary practices. Refined sugar consumption has risen since the 1970s from around 60 pounds per year to over 100 pounds today, with high-fructose corn syrup comprising most of that rise. Refined sugars inhibit absorption of vitamin B1 (thiamin), paralyze white blood cells and feed yeast (Candida albicans) which overgrows in the digestive tract which may deplete vitamin C and zinc.
Nutrients and blood tests are confusing
More confusion reigns when a person visits their doctor who may perform blood tests to determine if nutrient levels are sufficient. But these tests are often misinterpreted. First, a person’s vitamin blood concentrations may fall within the reference range (the commonly-occurring range), but that is not necessarily the healthy range. Second, blood levels may only reflect what a person has recently consumed. Third, does a high blood level indicate sufficiency or what is being excreted? A high blood-calcium level in a post-menopausal female does not indicate calcium adequacy, it indicates calcium is being lost from bone and excreted. Another example is vitamin B12 where blood levels may fall within the normal range but provision of supplemental B12 will often resolve symptoms caused by deficiency.
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So why water-down multivitamins?
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With all of this being said, inexplicably the Recommended Daily Allowance (RDA) may soon be watered down to the Estimated Average Requirement (EAR) by those nutritionists who feel many Americans are overdosing on essential nutrients. The EAR is intended to meet the nutritional needs of 50% of the population. This movement to reduce nutrients in fortified foods and multivitamin is underway despite the fact the RDA for vitamin C and vitamin D (signified by the ▲symbol in the chart below) won’t even significantly raise blood levels. This is particularly troublesome since vitamin C is water soluble and washes out rapidly in the urinary flow.
Furthermore, nutritionists have been remiss in factoring for a gene mutation that occurred many generations ago that halted the natural enzymatic conversion of blood sugar into vitamin C which occurs in most animals but not humans. While animals make vitamin C throughout the day humans must rely upon foods and supplements for this essential nutrient that builds connective tissue and piques the immune system. So much for reliance upon charts to determine nutrient needs.
The Entirely Safe Upper Limit
Then there are those nutrition advisers who mistakenly warn the public away from the upper limit (see chart below). But they forget to add that this is the entirely-safe upper limit. For example, this high-ranking web page on Google written by a "medical consultant" misguidedly warns people away from perfectly safe doses of nutrients. Actually, the Safe Upper Limit category is so misunderstood by the public it should be abandoned.
There are no observable side effects at the Safe Upper Limit dose, which is generally many times lower than the lowest-observed effects level (LOEL). And again, this requires interpretation because vitamins and minerals can be consumed in mega-doses to produce a therapeutic effect. For example, very high-dose vitamin D (50,000 IU) can be taken safely over a short-course to produce antibiotic peptides that kill off invading bacteria, viruses or even cancer cells. The same is true for mega-dose vitamin C which can be consumed in high doses to transiently produce hydrogen peroxide to kill off pathogenic germs or tumor cells.
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How much nutrition to protect DNA?
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Now let’s add a zinger to the debate on how much nutrition the human body really needs. Michael F Fenech, a prolific investigator at the Commonwealth Scientific and Industrial Research Organization Food and Nutritional Sciences in Australia, knowing we now live in an era of genomics (that branch of molecular biology concerned with the structure, function, evolution, and mapping of human genes), has begun to determine nutrient intake levels that protect the human library of about 25,000 genes that are packaged inside the nucleus of each living cell in the human body. Mutations in the DNA ladder that comprise the human library of genes can lead to disease.
Dr. Fenech proposes an RDA for genomic stability. For example, folic acid (vitamin B9) is required for DNA repair. How much folate from food or folic acid from supplements is needed to adequately repair DNA? Research by Dr. Fenech says about 700 micrograms per day, far beyond what the best diet could possibly provide. According to Dr. Fenech’s genomic RDA, humans need a lot more vitamin E and vitamin B12 to protect their genome than the RDA.
To corroborate what Dr. Fenech proposes, Dr. Bruce Ames, a prolific researcher at the University of California at Berkeley who has studies nutrients and DNA repair for decades now, says even marginal deficiencies of nutrients like folic acid or the trace mineral selenium can result in gene mutations and pre-disease states.
A disconcerting finding by Dr. Fenech is that mega-doses of three B vitamins, riboflavin (vitamin B2), pantothenic acid (vitamin B5) and biotin may be destructive to DNA. Accompanying antioxidant vitamins such as vitamin C, E and selenium may blunt some of the potential problems posed by overdose of these vitamins, but it is still a cause for concern given the paltry amount of these antioxidants in many multivitamins.
Summary: The RDA, EAR, AI, and DV are confusing, outdated and only mislead. They should be ignored. They serve to perpetuate nutrient deficiencies and even nutrient overload in the population at large. These flawed nutrient reference standards ensure a certain level of nutrient-related disease in the population at large because food fortification and dietary supplement regimens are designed around them. Greater attention should be given to research that addresses the amount of nutrients required to maintain DNA stability in aging populations.
LEGEND
NE = not established. No intake level has been established even though these nutrients are essential for human health.
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H – Recommended intake levels for nutrients are established for healthy individuals only and are not applicable to growing children, females in pregnancy, diabetics, smokers, the hospitalized, the medicated, individuals with chronic disease or infection or people living under chronic stress. Recommended intake levels address the minimum amount necessary to avoid frank deficiency, not intake level for optimal health.
▲ This dose will not significantly raise blood concentrations
* – Nutrients for which blood tests are notoriously inaccurate
** – Side effect level may in fact be therapeutic level (example: high-dose vitamin C generated hydrogen peroxide that can kill germs and cancer cells. Mega-dose vitamin D generates antibiotic peptides that attack germs and cancer cells.
x - Minerals that accumulate in full-grown males and post-menopausal females which may not be appropriate in those age groups.
☼ - The main source of vitamin D is skin exposure to mid-day unfiltered solar radiation.
1 GT - Genotoxic: can potentially cause gene mutations at typical dietary and supplement intake levels
2 Nutrition 2011 Mar; 27(3):293-7. PMID: 20688476 (Young males)
3 Mutation Research 2001 Apr 18;475(1-2):57-67 PMID:11295154
4 What we eat in America, NHANES 2007-08 www.ars.usda.gov/ba/bhnrc/fsrg
6 Am J Clinical Nutrition. 2006 Jun; 83 (6 Supplement):1483S-1493S PMID: 16841858
7 Upper Safe Levels of Intake for Adults: Vitamins and Minerals, University Nebraska, Accessed online Sept 7, 2011.
8 Vitamin A: National Academy of Sciences, accessed Sept 7, 2011
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