Incorrect Protein Percentages In Your Document?

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Incorrect Protein Percentages In Your Document?

Postby RusticBohemian » Mon Apr 24, 2017 1:56 pm

Hi Jeff.

I noticed that the percentage of calories derived from protein for the various foods you list in this document http://www.jeffnovick.com/RD/Q_%26_As/Entries/2013/8/27_Supplement_Recommendations_2_files/Protein%20In%20Veggies.pdf do not match up with what cronometer.com displays, despite drawing on the same USDA database of foods. The differences are sometimes considerable.

For instance:

You Hubbard Squash USDA #11490 - 19.8% protein (You)
Cronometer Hubbard Squash: 12.1% protein

You Pumpkin USDA # 11423 - 14.4% protein
Cronometer Pumpkin Cronometer: 9.2% protein

You Peaches USDA # 09326: 9.3% protein
Cronometer: 7.7% protein

You Corn: 14.2 % protein in
cronometer corn: 8.7% protein

You Lentils: 31% protein
Crononeter Lentils: 24% protein

The first thing I noticed was that you draw from USDA release number six, while cronometer.com draws from release #28.

But it seems implausible that two tests of the same food could have such vastly different results.

I wonder if you're using the assumption that there are 4/4/9 calories for carbs/protein/fat, or if you're using the figures from the USDA, which are 3.57 carb, 2.44 protein, 8.37 fat.

If not, do you know what the difference stems from?

Cronometer also claims to use conversion figures from the USDA.
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Re: Incorrect Protein Percentages In Your Document?

Postby JeffN » Mon Apr 24, 2017 2:23 pm

Thanks for checking my numbers.

First, if I used CRON-O-Meter as my source, then we would have to go directly to CRON-O-Meter (as you did) to check my numbers but I didn't. I used the USDA Nutrition Database SR itself, so to double check my numbers, you would have to go directly to the source I used. As we know, sometimes secondary sources round off, make mistakes, use adjustments, etc etc that were not part of the original source.

Second, I used Version SR 26 (not 6), which was the most current at the time. They are currently at SR 28, so we will have to use that.

Third, lets review and go through the numbers.....

RusticBohemian wrote:1) You Hubbard Squash USDA #11490 - 19.8% protein (You)
Cronometer Hubbard Squash: 12.1% protein


As per this link, my numbers are correct

https://ndb.nal.usda.gov/ndb/foods/show ... =1&Q6036=1


RusticBohemian wrote:2) You Pumpkin USDA # 11423 - 14.4% protein
Cronometer Pumpkin Cronometer: 9.2% protein


As pet this link, my numbers are correct

https://ndb.nal.usda.gov/ndb/foods/show ... =1&Q5948=1


RusticBohemian wrote:3) You Peaches USDA # 09326: 9.3% protein
Cronometer: 7.7% protein


As per this link, my numbers are correct...

https://ndb.nal.usda.gov/ndb/foods/show ... =1&Q4366=1


RusticBohemian wrote:You Corn: 14.2 % protein in
cronometer corn: 8.7% protein


As per this link, my numbers are correct

https://ndb.nal.usda.gov/ndb/foods/show ... =1&Q5540=1

There is one minor issue here, the NDB (Nutrition Database) number for peaches is 09236 and not the 09326 in my document which I will correct. the 09326 is watermelon so wouldn't have worked anyway. :)


RusticBohemian wrote:You Lentils: 31% protein
Crononeter Lentils: 24% protein


As per this link, my numbers are correct

https://ndb.nal.usda.gov/ndb/foods/show ... =1&Q9022=1


While it is not directly relevant to the above issue, but since you did mention it, you may want to check this article out about the 4/4/9

Accuracy In Nutrition: How Accurate Are The Atwater Values
http://www.jeffnovick.com/RD/Q_%26_As/E ... alues.html

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Re: Incorrect Protein Percentages In Your Document?

Postby RusticBohemian » Mon Apr 24, 2017 4:27 pm

I sent Aaron at Cronometer.com your response. His reply:

"The differences between Sr28 and Sr26 are minor, so the main difference here is they are using 4/4/9 and we're using the values USDA sr28 provides, and only use 4/4/9 when they aren't available. As with all nutrition data, it's all based on estimates and averages, but we believe the USDA conversion factors are more accurate than the over-simplified 4/4/9 method as they take into account the metabolic differences in specific types of carbs (fiber types, sugar alcohols, protein & fat composition) that would be otherwise missed with 4/4/9."
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Re: Incorrect Protein Percentages In Your Document?

Postby JeffN » Mon Apr 24, 2017 4:40 pm

RusticBohemian wrote:I sent Aaron at Cronometer.com your response. His reply:

"The differences between Sr28 and Sr26 are minor, so the main difference here is they are using 4/4/9 and we're using the values USDA sr28 provides, and only use 4/4/9 when they aren't available. As with all nutrition data, it's all based on estimates and averages, but we believe the USDA conversion factors are more accurate than the over-simplified 4/4/9 method as they take into account the metabolic differences in specific types of carbs (fiber types, sugar alcohols, protein & fat composition) that would be otherwise missed with 4/4/9."


I'm not sure who he means by "they," "we," and SR 28. I'm only using the values provided by SR28 in my links above which link directly to their numbers.

As I said, secondary sources sometimes modify things.

However, and most importantly, are the conclusions I made in the linked article on the Atwater (and other) values.

Therefore, since all these approaches have inaccuracies and not one of them is perfect, we either open a can of worms that can't be fully resolved, or we stick with a simple accepted formula that at least approximates the values and use it across the board for comparative purposes. This way, at least it is consistently inaccurate ;)

Otherwise, like with calories, we are only attempting to "nail jello to the wall" and trying harder is not going to yield any better results


More accurate does not mean accurate or precise (which doesn't exist in food analysis) and in the end, may be no better, espeically in relation to the perspective and principles I recommend in this forum.

Never, in 30 years I have I seen these minor differences in nutrition analyses matter to anyone's health improvement, healing or wellbeing, especially in regard to protein. In fact, I spend most of my time trying to get people to not worry about these numbers or the tracking of them.

How To Successfully Count Calories
http://www.jeffnovick.com/RD/Articles/E ... ories.html

Do You Know How Many Calories Are In The Food You Eat?
http://www.jeffnovick.com/RD/Articles/E ... u_Eat.html

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