Month: January 2008

I did some reading on how nutritional labels are done, it’s pretty interesting.

The Elements of Food

Let’s start out with the elements that make up food. No, I don’t mean carbon and such, I mean Fat, Protein, and Carbohydrates. Like the Greek idea of the 4 elements, those 3 elements are what are mainly considered for the labeling of food. There are other minor things, like vitamins, but Fat, Protein, and Carbohydrates are the big 3.

Presence by Subtraction

So when a food is analyzed in the lab, they usually determine chemically the fat and protein content. Anything left over is considered carbohydrates.

Probable Calories

Kilocalories (as they are referred to in the lab, or Calories, on packaging) are usually calculated by approximation. This means rather than measure the specific caloric content of a food, the previous data about Fat, Protein, and Carbohydrates (which was calculated by subtraction) is used. Take the protein and carbs and multiply them by 4, and take the fat and multiply it by 9. Add that up and you have your total Calories.
4*carbs + 4*protein + 9*fat = Calories.

A few months ago I made a simple JavaScript calculator to play with those numbers.

Round it Off

Numbers on the label are usually rounded, for ease-of-use.
Foods under 50 calories are rounded to the nearest 5-calorie increment, foods over 50 calories are rounded to the nearest 10-calorie increment.
For other nutritional info, it is usually rounded to the nearest whole number. Values under .5 can be shown as 0, and values between .5 and 1 can be shown as “<1”.

This is interesting because by rounding, a package with .49 grams of fat per serving and 10 servings would have 4.9 grams of fat in the package, even though the fat is listed as 0 on the label.

I’m not clear on if rounding occurs before or after calories are calculated, if it is before, than that package would contain 44.1 more calories than that shown on the label, since the fat was rounded off.

Some interesting information, anyway.

Oh, and if alcoholic products were labeled (which, sadly, they aren’t) in addition to Fat, Protein, and Carbohydrates, Alcohol would be included in caloric calculations, which is 7 Calories per gram.

One thing I noticed (which I mentioned below when talking about sugar) is that the more I try to understand and nutrition and adapt it to my own diet, the more critical other people are.

People initially criticized me for using Weight Watchers, since it’s an oversimplification. Now I use my own measurements, and they tell me that I’m not doing it right, because I’m not incorporating glycemic indexes into my dietary calculations. They criticize me for relying on the nutritional label for data, saying that the “sugar” line is meaningless. They tell me that you shouldn’t bother tracking your sodium intake, because it has no effect on health unless you are sensitive to it.

I’m trying to be positive, to feel good about myself, but I have to say, it’s damn hard sometimes when everyone is overwhelmingly negative with their feedback.

It’s very tempting just to tell them all to fuck off. Of course, that’s not right either, since they are *trying* to be helpful, even if the only way they know how is to point out all the weaknesses in my calculations.

I *KNOW* they aren’t perfect. I am dealing with spotty data, imprecise measurements, approximations, and estimates. But it is the best I can do, unless I want to devote most of the day calculating before I can eat anything. I like the system I have. Yes, it is flawed, but it’s easy to track, and gives me a fair amount of information.

So if you have helpful suggestions, things that you use yourself, of course I’m interested.

But if all you want to do is point out the flaws in my system, or espouse theoretical practices which you have never tried yourself, then I have to ask you, in the politest terms possible, to please fuck off consider your words.

I’m feeling kind of bummed…

I’ve been tracking my daily nutritional intake, trying to eat better, and one of the goals I set for myself (which I have stuck to pretty well) is to have less than 50g of sugar a day. For this, I go by the printed nutritional labels, which list sugar content as a line item.

I was feeling pretty good that I’d managed to cut most of the sugar out of my diet.

However, my girlfriend was pointing out the other night that me thinking this is an accomplishment is stupid, because ALL carbohydrates are sugars, so reducing the amount of “sugar” as shown on the label is meaningless, since the overall carbohydrate number is all sugar.

I feel helpless now, I mean, I don’t have the lab equipment to do my own food analysis (the lab guidelines book alone is $500), so all I can do is go by the labels…

Sigh… just when I thought I was starting to learn something about nutritional guidelines.

I’m thinking what I need is better literature…