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Metric Confusion? Don’t Worry About It

Are you confused by the metric system measures – grams and milligrams – commonly used to detail nutrition information on nutrition labels, and in your diabetes eating plan? You’re not alone. In fact, some people are so intimidated by grams and milligrams they find it very difficult to think about nutrition issues at all. If you have diabetes, however, you really must be equipped to think about nutrition issues – your long term health is at stake. So, how important is it for you to understand metric measures?

Metric system is logical

It is true that the metric system is logical – a gram is a measure of mass (weight), a milligram is 1/1000th of a gram and a kilogram is 1000 grams. Metric prefixes are the same for volume (milliliter) and distance (kilometer) too. The problem is there is no logical relationship between metric measures and common U.S. measures. A kilometer is 0.6241 U.S. miles, and a liter is 2.113 U.S. pints. Along those same lines, knowing there are 28.35 grams in a U.S. ounce is a conversion that’s impossible to make meal after meal. But, is it necessary?

In September, 1999, NASA’s $327 million Mars Climate Orbiter promptly crashed upon its arrival due to mix-ups between metric and U.S. measures. Making accurate conversions is very important in rocket science, but diabetes self-management is not rocket science. The truth is you don’t need to know what a gram actually is.

You simply need to know that there happens to be 15 of these “gram things” of carbohydrate – one carb choice – in a 3 ounce piece of white potato, and in ⅓ cup of cooked rice, and in a medium apple, and in one tablespoon of maple syrup. And, you need to know how many of the “gram things” of carbohydrate you should be eating each meal.

Trying to mix metric and U.S. measures led to the crash of the Climate Orbiter on the surface of Mars, but don’t let your anxiety about the metric measures used with in nutrition information crash your diabetes self-management effort. You can count carbohydrates perfectly, and still have no idea what a gram actually is. So, don’t worry about it.

This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.


  • Thomas A McAtee Jr. moderator
    8 months ago

    Thanks. It gets very confusing when you look at some of the nutrition labels and it’s measured in grams. It’s easy wehn seeing a cp or 1/2 cp etc but when looking at grams it’s something I just have to guess at when they’re talking about serving sizes. That’s what kicks me. The serving sizes being in grams.

  • Erica Franklin moderator
    8 months ago

    Thanks @tobys this can be very confusing. I spend more time in the grocery store looking at the nutrition labels and still feel a little lost and then I start comparing grams for 2 like items and really start a whole new chapter. This was a great article. Thanks again.

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