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1.4: Units of Measure

  • Page ID
    40558
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    In nutrition, there are two systems of commonly used measurements: Metric and US Customary. We need both because the US won’t adopt the metric system completely.

    The Metric and US Customary System

    These are commonly used prefixes for the Metric System:

    Micro- (μ) 1/1,000,000th (one millionth)
    Milli- (m) 1/1000th (one thousandth)
    Centi- (c) 1/100th (one hundredth)
    Deci- (d) 1/10th (one tenth)
    Kilo- (k) 1000x (one thousand times)

    Mass

    Metric System US Customary System Conversions
    Microgram (μg) Ounce (oz) 1 oz = 28.35 g
    Milligram (mg) Pound (lb) 1 lb = 16 oz
    Gram (g)   1 lb = 454 g
    Kilogram (kg)   1 kg = 2.2 lbs

    Volume

    Metric System US Customary System Conversions
    Milliliter (mL) Teaspoon (tsp) 1 tsp = 5 mL
    Deciliter (dL) Tablespoon (tbsp) 1 tbsp = 3 tsp = 15 mL
    Liter (L) Fluid ounce (fl oz) 1 fl oz = 2 tbsp = 30 mL
      Cup (c) 1 c = 8 fl oz = 237 mL
      Pint (pt) 1 pt = 2 c = 16 fl oz
      Quart (qt) 1 qt = 4 c = 32 fl oz = 0.95 L
      Gallon (gal) = 4 qt 1 gal = 4 qt

    Length

    Metric System US Customary System Conversions
    Millimeter (mm) Inch (in) 1 in = 25.4 mm
    Centimeter (cm) Foot (ft) 1 ft= 30.5 cm
    Meter (m) Yard (yd) 1 yd = 0.9 m
    Kilometer (km) Mile (mi) 1 mi = 1.6 km
    Query \(\PageIndex{1}\)

    This page titled 1.4: Units of Measure is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Jennifer Draper, Marie Kainoa Fialkowski Revilla, & Alan Titchenal via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.