Understanding Supplement Labels

Many supplements will show the actual grams (g) or milligrams (mg) of a mineral per ounce, scoop or pound. But many only show a “guaranteed analysis” – either “%” or “ppm”. So if you want to know how much of a mineral is actually contained in the scoop, you need to do some math. The math is not difficult, but can be confusing at first.
The same math can be used for converting bagged feed label nutrients and minerals into grams or mg.

Major Minerals

Major Minerals are used in large amounts and are usually shown as percent (%), which equals grams (g) of elemental mineral per gram of compound (or product).
The most confusing part is that the term “gram” is used both as the amount of mineral in a compound and as the total weight of the compound/product.
I will use the abbreviation “g” for the elemental major mineral.

For example, a supplement label shows it contains Calcium 6.5%

• The formula to calculate grams is
  percent ÷ 100 = g of mineral per gram of product or
  6.5 ÷ 100 = 0.065g calcium per gram of product
• There are 28.4 grams per ounce, so to see how many grams of calcium are in one ounce of the supplement, you would multiply 0.065 x 28.4.
  0.065 x 28.4 = 1.846
  There are 1.8g of calcium in each ounce of this supplement.
• The complete formula is:
  6.5 ÷ 100 x 28.4 = 1.846
• If the serving size is six ounces, then the complete formula is:
  6.5 ÷ 100 x 28.4 = 1.846 x 6 = 11 grams of calcium per serving
  

Trace Minerals

Trace Minerals are used in much smaller amounts – milligrams instead of grams. The term “ppm” (parts per million) is usually used to show how much of a trace mineral is contained in a supplement. PPM equals mg (milligram) of mineral per kg (kilogram) of product, so we will have to divide by 2.2 to get mg per pound and divide again by 16 to get mg per ounce.
You can use this to figure out how many mg of a trace mineral are contained in a supplement you use. Because supplement-feeding instructions are often “per ounce” (or per 1 ounce scoop), we will figure mg per ounce. (You may have to adjust this for your supplement.)

[1 kg = 2.2 lbs, 1lb = 16oz]

Example:

• Special Hoof contains copper at 540ppm
  ppm = mg per kg
• 540ppm = 540mg copper per 1 kg of Special Hoof
• 540 ÷ 2.2 = 245.5mg copper per 1 lb of Special Hoof
• 245.5 ÷ 16 = 15.3mg copper per 1 oz of Special Hoof or 91.8mg per six ounce serving

• Special Hoof also contains iodine at 4.7ppm
• 4.7 ÷ 2.2 ÷ 16 = 0.13mg iodine per 1 oz of Special Hoof or 0.78mg per six ounce serving
  

Trace Minerals rarely may be shown as percent (%). We treat it the same as for the major minerals above to convert to grams, then multiply by 1000 to see “mg”. [Note – if a supplement used this “non-standard” measurement for trace minerals, I would question if I really wanted to use this supplement.]

Converting A Typical Supplement Label

SuperDooperPooper Supplement guaranteed analysis

Calcium 6.5%
Magnesium 6%
Vitamin E 5,600IU per lb
Selenium 12.7 ppm
Copper 1250 ppm
Manganese 2400 ppm
Zinc 2400 ppm
Feeding directions – feed 2 to 3 ounces daily

What it contains per ounce

Calcium 1.8g [ 6.5 ÷ 100 x 28.4 = 1.846 ]
Magnesium 1.7g [ 6.0 ÷ 100 x 28.4 = 1.704 ]
Vitamin E 350IU [ 5,600 ÷ 16 = 350 ]
Selenium 0.36mg [ 12.7 ÷ 2.2 = 5.77 ÷ 16 = 0.36 ]
Copper 35.5mg [ 1250 ÷ 2.2 = 568.18 ÷ 16 = 35.5 ]
Manganese 68.2mg [ 2400 ÷ 2.2 = 1090.9 ÷ 16 = 68.18 ]
Zinc 68.2mg [ 2400 ÷ 2.2 = 1090.9 ÷ 16 = 68.18 ]

For 3 oz serving, multiply the above by 3


Symbols for Common Minerals

Major Minerals

Ca - Calcium
P - Phosphate
Mg - Magnesium
K - Potassium
Na - Sodium

Trace Minerals
Fe - Iron
Cu - Copper
Z - Zinc
Mn - Manganese
Co - Cobalt
I - Iodine
Se - Selenium
Cr - Chromium
Mb - Molybdenum (considered contaminant from industrial pollution)
Al - Aluminum (considered contaminant from acid rain)


Some Handy Terms

Gram – g or gm
Milligram – mg
Microgram – mcg or µ
Kilogram – kg
Parts per million - ppm
IU - International Units (commonly used for fat soluble vitamins)

1 g = 1000mg (multiply g by 1000 to get mg or divide mg by 1000 to get g)
1mg = 1000mcg (divide mcg by 1000 to get mg, multiply mg by 1000 to get mcg)
1kg = 2.2 lbs
1lb = 16 oz
1lb = 453.6 grams
1oz = 28.4 grams