Reading Labels - Fat Soluble Vitamins

~ September 1997 No.14 ~

You have read all the articles, done all the talking and made up your mind. The next step is to take the plunge and actually buy a nutraceutic product. It’s not that easy. You have to face the huge array of choices available on the drug or health food store selves. Then , of course, there is the challenge of figuring out the product label. No two seem to be the same. Legislation on labeling exists in most countries, but it seems that the rules were made to help the bureaucrats not the consumer.

Nutrition Label

The most important part of the label is usually the list of ingredients. In the case of vitamin pills the list may contain names that are well known, but not necessarily. Then there are always things in brackets. And of course there are always the units of weight or concentration. It all can be very confusing unless you know what you are reading and what it means.

Unfortunately over the years many common vitamins have had different names. Some of the names are historical, some are related to the chemical properties of the vitamins and some are just names given by the discoverer of the vitamin. Below is a list of the fat soluble vitamins and some of the names that you might find on a vitamin pill bottle label. Vitamins are generally divided into two broad categories, water soluble vitamins and fat soluble vitamins, based on how well they dissolve in fat. This is a very important division because it is often related to how the particular vitamin is absorbed into to the body from the intestines.

Fat Soluble Vitamins

Table 1: Vitamin D
Other names :vitamin D2 ; vitamin D3 ; cholecalciferol
Forms found in vitamin supplements :vitamin D
Forms found in the body :vitamin D2 (calciferol) ; vitamin D3 (cholecalciferol); phosphate esters of vitamin D2 ; phosphate esters of D3 ; 25-hydroxycholecalciferol ; 1,25-dihydroxycholecalciferol ; 5,25-dihydroxycholecalciferol
Units of concentration :International Units or I.U.’s ; 1 I.U. = 0.025 ug of vitamin D3
Toxicity :toxicity in children can occur at doses of 4,000 I.U. and 75,000 I.U. for adults

 

Table 2: Vitamin E
Other names :alpha-tocopherol
Forms found in vitamin supplements :dl-alpha-tocopherol acetate
Forms found in the body :d-alpha-tocopherol ; tocpheronolactone ; phosphate esters of d-alpha-tocopherol ; phosphate esters of tocpheronolactone
Units of concentration :International Units or I.U.’s ; 1 I.U. = 1 mg dl-alpha-tocopherol acetate
Toxicity :negligible even at high intake levels

 

Table 3: Vitamin A
Other names :retinol, vitamin A1
Forms found in vitamin supplements :beta carotene ; vitamin A acetate ; vitamin A palmitate
Forms found in the body :retinol ; esters of retinol ; 3-dehydroretinol ; esters of 3-dehydroretinol ; retinal ; 3-dehydroretinal ; retinoic acid
Units of concentration :International Units or I.U.’s ; 1 I.U. = 0.344 ug vitamin A acetate ; 1 I.U. = 0.3 ug retinol
Toxicity :toxicity can occur following ingestion of large quantities of liver or fish liver oils

 

Table 4: Vitamin K
Other names :vitamin K3 ; menadione ; prothromin factor
Forms found in vitamin supplements :menadione
Forms found in the body :vitamin K2
Units of concentration :mg
Toxicity :difficult to achieve

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Last modified

June 04 2015