Friday, August 6, 2010

Size matters. But not how you think.

The facts about serving size and portions.

What do a quarterback, toddler, 90 year old woman and you have in common? Very little, I suspect. And yet each will glance at the nutrition label on packaged foods and observe the serving size. Some may measure it, others might strive to meet it, and many will ignore it. But most of you will expect that you should be sticking to the stated portion. At least most of my blog readers.
So what is the serving size declared on the label really for? It is simply a way to define nutrition information, required by the FDA. And most serving sizes are standardized by product. For instance, approximately 1 ounce of cereal or ½ cup of ice cream, regardless of the brand, are considered the serving sizes. This way consumers know that the information (the protein, calcium, etc.) are based on that serving size listed on the label. And the calorie content for that same serving can vary significantly!
Yet most people I’ve discussed this with believe that the serving size is the amount they are supposed to be eating. And not a morsel more! You measure out 1 oz of cereal for breakfast, the right amount according to the label, and you are left feeling that the problem lies with you. “Why isn’t this enough?” you may ask yourself.  Well, does it make sense that the football player, the growing child and the sedentary woman would all need exactly the same amount of calories, of fuel? And that that amount is also appropriate for you? Clearly not!
If you don’t follow the rules, the amount you were supposed to limit to, you may feel that you have slipped. Yet neither Kellogg nor the FDA knows how much you actually need to eat for breakfast. And neither do I. The only one who can truly judge is you.
I often use the analogy of titration. For those of you who have long forgotten chemistry, it is the process of figuring out just how much of a substance is necessary to cause a reaction. Take a look at this for a quick visual:
One clear liquid is added to another, drop by drop, until the point when a reaction happens. In this titration, the solution turns pink. Could they dump all of one substance into the other and have the reaction occur? Sure. But they are looking for the point where it is just enough of the added substance to turn pink.
Continuing with the food analogy, we could eat a lot at once, and have the “fullness reaction” happen, just like you could combine these two clear liquids all at once and have it turn deep pink. But with eating, we are looking to identify just the start of “pink”, so to speak. And it takes a while for us to master our own food and eating titration. So you may be disappointed if you are expecting a quick reaction.
The point? The nutrition label isn’t the answer to knowing how much you need—to knowing how much will put you “in the pink”.  It is a process to figure out just how much your body needs to eat at any time. It takes time after eating your meal to sense fullness (see the Tylenol reference in previous blog entry). And it takes time to identify your eating patterns.
If eating the portion size stated on the label leaves you hungry an hour later then clearly that amount is not enough. So in addition to eating a snack then, be sure to increase your portions next time you eat breakfast and assess how that feels.
And if you can’t tell if your portions are excessive resulting in “deep pink”, consider reducing your portion by 25% and see how you feel. Perhaps that will still get you in the pink, closer matching your need for fuel and energy balance.

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