# Thread: Sweet Potato Calorie Question - Perplexed

1. ## Sweet Potato Calorie Question - Perplexed

Hello Everyone -

So recently I've become more and more successful with fat loss and based on hydro static measurements have gone from 20% to 13.5% BF. My next goal is to get to 10%.

I realize this will take even more precision with calorie counting as the tolerances will become smaller and smaller. So I am re-examining ALL of my food's calorie values with a fine toothed comb.

One of the starches I was eating was "4oz of roasted sweet potato", basically get a sweet potato, cut it up, throw it in a roasting pan for 40 minutes and then "weigh out" 4oz of this with my protein. I was "counting" this as about 100 calories, based on the the nutrition data website - E.G., 4 x 1oz 26 is about 100 cals.

The problem is this value is wrong, or has to be, something is wrong because of two facts:

1. Sweet potato loses 50% of its weight after cooking. This is empirical fact. You can weigh a raw sweet potato at 10z, cut it and roast it for 45 minutes and the cooked pieces will weigh 5oz if you put them back on the scale

2. The nutrition data for "raw" sweet potato is the same as cooked (+ or - 2 calories): see nutritiondata.self.com - 1 oz is 24 calories, or 96 cals.

So, based on logic alone, one of these three things has to be false:

1. Sweet potato doesn't lose 50% of its weight when you cook it. (but it does)
2. The calorie value for "unprepared sweet potato" is wrong
3. The calorie value for "cooked sweet potato" is wrong

Or else cooking is "magic" and makes 50% of the calories vanish (this is patently false).

Now, normally this isn't a big deal if you body fat is 20%, but now this is a difference of 100 calories! Over a week this is 700 calories.

Can someone with some knowledge and experience in this area please explain. Should I count my 4oz of roasted sweet potatoes as 200 calories or 100 calories?

Any help appreciated

2. weigh it raw
use the stats for raw
then cook and eat

3. Originally Posted by determined4000
weigh it raw
use the stats for raw
then cook and eat
Always this

Even with frozen foods (i.e. chicken breasts), just weigh raw and use that number to calculate.

As long as you follow the same method with consistency, you can then adjust as required.

4. The most overthinking over 4oz of sweet potato I think I'll ever see.

5. Originally Posted by ErikTheElectric
The most overthinking over 4oz of sweet potato I think I'll ever see.
All I have to say is sweet potato brownies

6. Originally Posted by ErikTheElectric
The most overthinking over 4oz of sweet potato I think I'll ever see.
Yeah sure it's overthinking, but I've only been successful because I am being super anal about weighing and measuring my food and keeping under my calorie expenditure.

When I get my bodyfat testing done they give very specific calorie predictions based on my LBM so why not be as precise as possible?

I mean, why have the guesswork? Wouldn't you want it to be as accurate as possible? 100 calories is an extra light beer

It's not like this is a margin of error of 10 calories, this is a possible margin of error of 100 calories which is a lot for a cut multiplied by the number of days.

So I guess the consensus is to use the raw weight just to be safe - so 4oz of cooked sweet potatoes counts as 8 oz of raw, so 200 calories.

Thanks

7. Originally Posted by bdournaee
Yeah sure it's overthinking, but I've only been successful because I am being super anal about weighing and measuring my food and keeping under my calorie expenditure.

When I get my bodyfat testing done they give very specific calorie predictions based on my LBM so why not be as precise as possible?

I mean, why have the guesswork? Wouldn't you want it to be as accurate as possible? 100 calories is an extra light beer

It's not like this is a margin of error of 10 calories, this is a possible margin of error of 100 calories which is a lot for a cut multiplied by the number of days.

So I guess the consensus is to use the raw weight just to be safe - so 4oz of cooked sweet potatoes counts as 8 oz of raw, so 200 calories.

Thanks

Dude.

It's only 100 CALORIES.

8. Originally Posted by ErikTheElectric
Dude.

It's only 100 CALORIES.
I get where you are coming from and in this case for one 4 oz serving, if everything else in my diet is dialed in it probably won't make a difference. But then I think it will as I get lower and lower BF %.

But then also think about someone else who say, happens to eat 8 oz of roasted sweet potatoes, they think they are getting 200 cals and its really 400 cals -all because they didn't weigh the food raw - they went to the nutrition database for roasted sweet potatoes and used this value and then complains that "cutting doesn't work" when in reality they were going over cals. Just sayin'.

I wonder how many other foods are like this. It makes me want to use a different starch that doesn't have this inconsistency.

I think weighing it raw is the safe, conservative way to get the accurate calories but still doesn't explain why the nutrition database is wrong for the roasted potato value.

9. As long as your consistent when you weigh it you should be able to adjust if you're gaining or losing more than you'd like

If you're eating 4 oz after cooking and you're gaining more weight than you'd like simply adjust.

I know what you're saying about trying to be precise, but you'll need to monitor your progress anyway and make changes as you go. If at 13% you're dropping weight then you're in a deficit, end of story.

I'm pretty anal about weighing things out too, but it's all relative to the changes your body is constantly undertaking, so if you're consistent in how you weigh you'll be able to adjust as you see fit.

Strong overthinking.

10. Originally Posted by bdournaee
I get where you are coming from and in this case for one 4 oz serving, if everything else in my diet is dialed in it probably won't make a difference. But then I think it will as I get lower and lower BF %.

But then also think about someone else who say, happens to eat 8 oz of roasted sweet potatoes, they think they are getting 200 cals and its really 400 cals -all because they didn't weigh the food raw - they went to the nutrition database for roasted sweet potatoes and used this value and then complains that "cutting doesn't work" when in reality they were going over cals. Just sayin'.

I wonder how many other foods are like this. It makes me want to use a different starch that doesn't have this inconsistency.

I think weighing it raw is the safe, conservative way to get the accurate calories but still doesn't explain why the nutrition database is wrong for the roasted potato value.
It's not wrong. The value is for a raw weight. You are weighing it cooked so you are making it wrong. Not sure how that's hard to follow.

11. Originally Posted by MrM27
It's not wrong. The value is for a raw weight. You are weighing it cooked so you are making it wrong. Not sure how that's hard to follow.
Actually, it is listed incorrectly per my original post. I can't post links since I don't have enough total posts, but you can clearly see the following:

Go to nutritiondata.self.com
Find "Sweet potato, cooked, baked in skin, with salt"
For 1 oz it is listed at 26 cals/ounce. COOKED.

Then select the value for raw, Sweet potato, raw, unprepared.
For 1 oz it is listed at 24 cals/ounce. RAW.

For the sake of argument, lets say ~24 cals/ounce == ~26 cals/ounce. Approximately the same.

The problem is, when I bake chopped up sweet potatoes they lose 50% of their weight (try it). This means the cooked calories are off double! 4oz of cooked sweet potatoes was 8oz of raw, so 200 cals, not 100. The database is wrong. This is something I can manage around but is surprising, per my earlier point if someone ate 8-12 ounces of cooked sweet potatoes they are really getting 200-300 cals not 100-150.

12. Your concern is leaving the realm of bodybuilding and entering the realm of basic physics. Mass is neither created nor destroyed. Unless you witness half of your potatoes evacuating the oven in protest, the important parts of the potato are still exactly where you left them. You are losing water weight from your potatoes during the roasting process, and water has a caloric value of 0.

Yes, your referred website is incorrect. You should inform them. So weigh them raw for counting purposes, and enjoy.

13. The weight nutrition data is using for that calorie count is 28g raw, not 28g roasted. If you select the 5th choice down for Sweet potato, cooked, baked in skin, without salt [Sweetpotato] the serving size is given as 1 medium (2" dia, 5" long, raw) (114g) for 103 cals per serving. This is right at ~25-26 cals/ounce. I can see how you could make the mistake, just fix it and move on.

I know everything I cook that I'm going to log I weigh raw, as raw weight =/= cooked weight (which you have found out) due to loses of water weight,etc in the cooking process.

Just a fun side note, I find most of the food I cook/fry/bake weighs 70-80% its raw weight once cooked.

14. Originally Posted by jonnicola
All I have to say is sweet potato brownies
holy fuk yum

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