Copper %RDA wrong: different value in 100g food vs 100g added to diary - w/o using custom limits

I added 100g "grape leaves, canned" to my diary. Copper: 1.8mg = 205%

I looked up "grape leaves, canned" in the "Foods" tab, set it to 100g. It has 1.8mg copper = 92%

The latter % is the correct value.

I checked in my diary what limits are used. It was set to 0.9mg minimum, which explains the incorrect 205%.

BUT I have not used custom limits! (checkmark at "use custom values instead of RDA was unchecked)

(PS: I would be happy to post you screenshots if you would resolve the bug that your configuration of vanillaforums does not allow any normal simple way to upload pics. - Which issue we discussed already and you offered some wonkaround using yetanother website that I do not use.......... but I know that vanillaforums does not generally have this problem so it is something in this installation.)


  • edited February 2019

    Quite a huge error in %RDA

    I have set now the correct RDA of 2mg and checked the checkbox to use custom values and now the Food tab and the diary entry displays the same.

    The problem about this bug is that it made me frightened and lose trust: do I need to double verify everything Cron tells me?

  • Hi Lolinda,

    The percent Daily Value (% DV) is shown in the Foods tab. This value is based on a 2000 kcal diet and is meant to help you compare the nutrition information of different products. This is how nutrition information is presented on food labels in the US.

    These are different from the RDAs - these are based on your age, sex and lifestage and provide more specific recommendations for you.


    Karen Stark
    As always, any and all postings here are covered by our T&Cs:

  • edited February 2019

    Thanks for replying.

    Here I read that the 2.0mg is actually the outdated label value:
    For U.S. food and dietary supplement labeling purposes the amount in a serving is expressed as a percent of Daily Value (%DV). For copper labeling purposes 100% of the Daily Value was 2.0 mg, but as of May 27, 2016 it was revised to 0.9 mg to bring it into agreement with the RDA.[149]

    • For your consideration. I just want to help improving Crono.
      (And for myself, I have some work to do: check all Crono limits ... this was a very useful problem to show up... I learned that limits can differ by more than 2x!!)
  • Thanks very much! I will check out the updated FDA labeling rules for our American 2016 label-type.


    Karen Stark
    As always, any and all postings here are covered by our T&Cs:

  • Hi Lolinda,

    If you choose the American Label-type (this is the standard label that was used prior to 2016) this uses the "old" %DVs.

    Beginning in 2016 the FDA started to phase in the updated label format, including some new % Daily Values. For this label format, use the drop-down menu above the label in the Foods tab and choose American 2016, shown here:

    This option uses the updated % Daily Values from the FDA. For example, the %D V for copper is 0.9 mg:

    Cronometer has both options available because the new label (American 2016) is still being phased into use; there are still many labels out there using the old format and values. This way you can choose the label type that is best for your purposes!

    Thanks for your attention to detail!


    Karen Stark
    As always, any and all postings here are covered by our T&Cs:

  • appreciated! (and I add that you guys at Crono don't have an easy job at all... all these different international standards.....)

  • I have sent another suspect for a calculation bug by email. Easier by mail as it has a lot of screenshots.

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