Upper intake levels

Due to bleeding risk, individuals on anticoagulant therapy or individuals who are vitamin K-deficient should not take vitamin E supplementation without close medical supervision. Absent of that, vitamin E is a well-tolerated relatively non-toxic nutrient. A tolerable upper intake level of 1,000 mg daily of a-tocopherol of any form (equivalent to 1,500 IU of RRR a-tocopherol or 1,100 IU of all-rac-a-tocopherol) would be, according to the Food and Nutrition Board of the Institute of Medicine, the highest dose unlikely to result in haemorrhage in almost all adults. 

SCF (2000). Opinion of the Scientific Committee on Food on the Tolerable Upper Intake Level of Beta Carotene. Scientific Committee on Food, http //europa.eu.int/comm/ food/fs/sc/scf/index en.html. 

Vieth, R. (2006). Critique of the considerations for establishing the tolerable upper intake level for vitamin D Critical need for revision upwards. /. Nutr. 136,1117-1122. 

EFSA, European Food Safety Authority, Tolerable upper intake levels for vitamins and minerals. EFSA, Parma, Italy, February 2006. 

Upper intake level (UL) of vitamins. The UL is defined as the highest level of intake of a nutrient that will not pose a risk of adverse health effects to most individuals in the general population. The UL is an important reference standard, especially with the current promotion and wide availability of vitamin preparations. A table of the DRIs for vitamins is available on the lOM s web site at http //www.nationalacademies.org/IOM/IOMHome. nsf/Pages/Ongoing+Studies FNB. 

Opinion of the Scientific Panel on Dietetic Products, Nutrition and allergies on a request from the commission related to the tolerable upper intake level of fluoride, EFSA J. 192 (2005) 1-65 (Available at http //www.efsa.eu.int/science/nda/nda opinions/catindex en.html). 

Tolerable Upper Intake Level (UL) UL is the highest average daily nutrient intake level that is likely to pose no risk of adverse health effects to almost all individuals in the general population. As intake increases above the UL, the potential risk of adverse effects may increase. The UL is not intended to be a recommended level of intake. ULs are useful because of the increased availability of fortified foods and the increased use of dietary supplements. The UL applies to chronic daily use. For some nutrients, there may be insufficient data on which to develop a UL. 

Comparison of the components of the Dietary Reference Intakes. EAR = Estimated Average Requirement RDA = Recommended Dietary Allowance Al = Adequate Intake UL = Tolerable Upper Intake Level. 

ScientiE>c Committee on Food, Guidelines of the Scientil>c Committee on Food for the development of tolerable upper intake levels for vitamins and minerals SCF/CS/ NUT/UPPLEV/11 FINAL, 28 November 2000 http //ec.europa.eu/food/fs/sc/scf/ out80a en.pdf... 

Johnston CS (1999) Biomarkers for establishing a tolerable upper intake level for vitamin... 

Optimal dietary intake is difficult to determine. Dietary Reference Intakes (DRIs) in the US are reference values that are quantitative estimates of nutrient intakes to be used for planning and assessing diets for apparently healthy people. DRIs are composed of reference values including Estimated Average Requirements (EARs), Recoimnended Dietary Allowances (RDAs), Adequate Intakes (AIs) and Tolerable Upper Intake Levels (ULs). Most nations have established the eqnivalent ofthe US DRIs. These are consensus and statistical valnes obtained from retrospective public health dietary studies, controlled experiments on metabolic wards, epidemiological surveys, isotopic tracer investigations, and extrapolation from animal models. 

The average daily dietary intake of phosphorus in the developed world is approximately 1,000 mg, which exceeds the 700 mg adequate daily intake level for adults estabhshed by the Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences (www.10M.edu). The same group defines the tolerable upper intake level for phosphorus as 4 g for most adults, but 3 g for adults over the age of 70. Phosphorus intake varies with the composition of the diet, and foods that are rich in phosphate include eggs, milk products, meat, and fish. 

The optimal dietary requirements of vitamin E for humans are not yet known, especially with the emergence of new paradigms regarding adequate levels of dietary micronutrients (Chalem, 1999). Recommendations in the United States and Canada have been reevaluated, and a new concept of Dietary Reference Intake (DRI, 2000) was issued for vitamin E and other antioxidants. The DRI recommendation should prevent specific deficiency disorders, support health in general ways and minimize the risk of toxicity, which carries more tasks than the previous recommendations (DRI, 2000). Accordingly, the recommendations for intakes were set to higher levels than previously. Estimated Average Requirements (EAR) for adults, both men and women, were set to 12 mg a-tocopherol/day, RDA to 15 mg/day and Tolerable Upper Intake Level (UL) to 1000 mg/day. Moreover, the EAR and RDA are based only on the 2R-stereoisomeric forms of a-tocopherol, because the other vitamers... 

The findings of these and other studies have led the Food and Nutrition Board of the U.S. Institute of Medicine to recommend a tolerable upper intake level of3000 tg/day of preformed vitamin A for men of 19 years and older, with lower levels for women of child-bearing age, infants, children, and adolescents. Carotenemia results from a chronic excessive intake of carotene-rich foods, principally carrots. This condition, in which yellowing of skin is observed, is benign, because the excess carotene is deposited rather than converted to vitamin A. 

Probably as a result of its limited solubility and limited gastric absorption, no adverse effects have been associated with ingestion of riboflavin appreciably above RDA levels. One study reported no short-term side effects in 49 patients treated with 400mg/day of riboflavin with meals for at least 3 months. Because of a lack of data for risk assessment, no tolerable upper intake level has been proposed for riboflavin. ... 

No adverse effects have been associated with excess vitamin Bi2 intake from food or supplements in healthy people. Daily oral doses of up to 2 mg of cyanocobalamm can be used for treatment of deficiency in those who can tolerate oral supplementation. There are insufficient data in the literature to propose a tolerable upper intake level for vitamin Bj2. ... 

No adverse effects of biotin in doses of up to 300 times a normal dietary intake have been reported, as in patients with biotinidase deficiency. Tolerable upper intake levels for biotin have not been set, because there are insufficient data. ... 

There are no reports of adverse effects. With the exception of occasional mild diarrhea, with oral pantothenic acid m doses as high as 20g/day. In the absence of evidence of toxicity, a tolerable upper intake level cannot be derived for pantothenic acid. 

Considering the Intake data at various percentile levels, new interpretations come forward. In all cases the values are skewed toward the upper Intake levels, thus all subjects at the 50th percentile report consumption below the mean intake level. For women at the 25th percentile the average Intake was approximately 7 mg of iron per day and at the 10th percentile the intake was down to only 5 mg per day. The males at the 25th... 

A Tolerable Upper Intake Level (UL). The UL is the maximum intake by an individual that is unlikely to pose risks of adverse health effects in almost all (97-98%)individu-als. It includes intake of a nutrient from all sources (food, fortified food, water, and sup-dements). Water can include fluoride and minerals depending on the source of water. "Tolerable" is used to "avoid implying any possible beneficial effect." It is the amount of vitamin that can be "tolerated" without the person s exhibiting or experiencing adverse reactions. The UL should not be considered the upper dose for those who self-dose with megadoses of vitamins. 

Hypervitaminosis K. Although it is possible to overdose with this vitamin, the fact that it is available only over the counter in small doses in multivitamin preparations has resulted in little knowledge of any toxicities. Toxicities do not appear in animals administered large doses. It is known that excess intake of the vitamin does not promote clot formation. There is no Tolerable Upper Intake Level. 

Hypervitaminosis Thiamine. The vitamin is considered very safe. There are no Tolerable Upper Intake Levels. Possibly the rate-limiting phosphorylation step in the intestinal mucosa reduces the risk of toxicity. The percentage of thiamine absorbed decreases as the dose increases. 

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