

Show HN: Nutrients Per Calorie, a web interface to the USDA foods database - ryanatkn
http://ryanatkn.github.com/nutrients-per-calorie

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bink-lynch
This is great! My wife and I were just discussing the nutritional value of
amaranth (Calcium in particular) and then I saw this.

To be clear, the bottom bar graph represents what 2000 calories of that food
would contain of that nutrient? Being used to reading ingredient labels and
the recommended values, I was thinking amaranth contained ~90% of Calcium per
serving, then I watched the video. Do I understand this correctly? If so, you
might want to label that somehow.

Very nice work! We love it!

Thanks!

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ryanatkn
Thanks for the feedback!

Yes, that's correct, but everything is relative. The recommended daily intake
is the recommended nutrient amount divided by 2000 calories, and this value is
then compared against every other food. The bars for each nutrient are
calculated according to the formula ((nutrient/calorie)/maxValue), where
maxValue is the highest (nutrient/calorie) in the comparison set, and the
result is a percentage of the maxValue, and is the percentage the bar is
filled. So it's all relative - the highest value will always be a full bar. If
something has half as much per calorie, the bar will be half-full. On the
nutrients page, there is no daily value that's being compared against - it's
just foods against each other.

Measuring something per-serving isn't something that you can glean from the
data as presented. For amaranth, if you compare it to the recommended daily
intake, you'll see a full bar for amaranth and just a sliver for the
recommended daily intake, meaning 2000 calories of amaranth would have way
more calcium than you need. More usefully, the app can show you how amaranth
compares against other foods to help you make choices. I'll think about how
per-serving data could be included - thanks!

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bink-lynch
Thanks for the explanation. I figured there was no per serving information
from the data. Seems like there would not be a consolidate source for that.

I get it now. Again, nice work!

