T Nation

Nutritional Information -- Who to trust?


I bought some lentils recently, then I ate them. According to the package, the 128 grams (dry) I made for myself had 280 calories. However, the meal felt pretty heavy, so I looked up the nutritional information for dry lentils online and found this: http://nutritiondata.self.com/facts/legumes-and-legume-products/4337/2

So according to this site (which says the information was supplied by "USDA SR-21"), those 128 grams of lentils should have ~452 calories. That's a pretty big difference from 280. Now both brands of lentils I bought (Jack Rabbit and Stop & Shop) give the same numbers, 32g gives 70 calories.

So what do you trust, what's on the package or what the USDA says?

I was also doing the math on the link above. According to Nutrition Data 100g of dry lentils have 60g of carbohydrates, 30g of fiber, 26g of protein, and 1g of fat. Now, I was under the impression that fiber, being listed within the carbohydrate section, is added to the total carbohydrate value listed. Also, fiber presumably has no calories. That means we have 30g of carbs, 26g of protein, and 1g of fat, giving 30*4 + 26*4 + 1*9 = 233 calories in 100g of dry lentils. Then 233*0.32 = 74.56, very close to the information on my packaged lentils. But if I don't subtract the fiber from the carbohydrates then we have 60*4 + 26*4 + 1*9 = 353 calories, which is exactly what the USDA lists for 100g of lentils.

I'm vexed.


You don't absorb fiber, so it isn't counted in the calorie total.
Most labels are approximate too.


Okay, so I was confused because whenever you look at nutritional information you see fiber listed under "Total Carbohydrates", but tabbed forward as if it was grouped under "Total Carbohydrates". Also you see sugar tabbed forward under "Total Carbohydrates", and I would assume that sugar is included in the total carbohydrate count.

Anyway, I don't doubt that there's a degree of approximation, but we're talking about a very significant difference (~62%), not a small margin of error. That's also why I provided the numbers of carb/protein/fat listed, because those are the only significant sources of calories. You can easily calculate about how many calories should be in anything by multiplying (carb + protein)4 + fat9. The only question is whether you subtract fiber from the carb total.


Not 100% true. Soluble fiber contributes a small amount of calories (1-2.5 cal/g dependent on the type of soluble fiber) usually due to the fermentation into short chain fatty acids by colonic bacteria. Obviously, the caloric contribution in this instance way less significant than what you would find in the typical non-fibrous carbohydrates.


Seem to always get the opposite as this, after a night out drinking, I drop 3-5 pounds normally due to dehydration. Takes 3-4 days to get back to my original weight.