Units of Measure

University of Hawai‘i at Mānoa Food Science; Human Nutrition Program

The Metric and US Customary System

In nutrition, there are two systems of commonly used measurements: Metric and US Customary. The US Customary system of measurement is primarily used in the United States. These are commonly used prefixes for the Metric System:

Table 1.6 Common Prefixes for the Metric System
Prefix	Amount
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

Table 1.7 Common Mass Units for Metric and US Customary Systems
Metric System	US Customary System	Conversions
Microgram (μg)	Ounce (oz)	1 oz = 28.35 g
Milligram (mg)	Pound (lb)	1 lb = 453592 mg
Gram (g)	Pound (lb)	1 lb = 454 g
Kilogram (kg)	Pound (lb)	2.2 lbs = 1 kg

Volume

Table 1.8 Common Volume Units for Metric and US Customary Systems
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

Table 1.9 Common Length Units for Metric and US Customary Systems
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

Learning Activities

Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are available in the web-based textbook and are not in downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document).

Learning activities may be used across various mobile devices; however, for the best user experience, it is strongly recommended that users complete these activities using a desktop or laptop computer.

License

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Human Nutrition 2e Copyright © 2022 by University of Hawai‘i at Mānoa Food Science and Human Nutrition Program is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted.