Have you ever wondered why the serving size on a box of granola (maybe cereal if that’s your thing) is the serving size? Like, why was it decided that 1/4 cup of granola was a serving size?

I wondered that same thing for awhile.

On all foods that are packaged and have nutrition labels there will be a “serving size” that is based off a “2000 calorie diet.” Why is 2000 calories that number that decided for a daily caloric intake? Well, 2000 calories was decided upon by the USDA as a good estimation of calories for a 135lb woman to maintain weight. The calculation that was used was 15 calories x lbs bodyweight. Thus, 135lb x 15 will give that woman 2000 calories to maintain weight. This is a very old calorie equation that is actually decently accurate.  Pretty simple right? Yup, that is the what the USDA is looking for and overall, I don’t think that is a bad plan. It gives someone a good starting point for serving size, without knowing any specifics about the individual person reading the food label.

But, there are a few problems that can make this confusing and in my opinion can be detrimental for someone new to reading food labels….a few things to be aware of.

1. Obviously not everyone is a 135lb woman. If you didn’t know the 2000 calorie diet was for that specific woman, you would be confused. For example, I weigh 185lb so following the above the equation of 15 x 185lbs I should eat around 2800 calories to maintain weight. This means that the 1/4 cup of granola is still the serving size for her or me, but if I eat more of the granola I will more easily be able to fit the extra calories into my 2800 calories for the day. This doesn’t mean the 135lb lady can’t eat more of the granola than the serving size, it simply means if she eats more she will have to limit calories elsewhere in her day to stay at or around 2000 calories.
2. Even 135lb women are different and might need different calorie recommendations based off age, body fat % and activity level.
3. You shouldn’t use a food label to decide how many calories you should consume of a food each day. Remember, food labels are simply a good starting point for serving size so you don’t over eat. To find how many calories you should eat, there are better online calorie calculators like this one. Then you should be using a food tracking app like Myfitnesspal while weighing yourself weekly to see how many calories will help you lose, gain or maintain weight. Food labels can’t give you all the information you need in regards to caloric intake.
4. Do you know if you want to lose weight, gain weight or maintain weight? That will determine how many calories you should eat each day. For the 135lb lady, if she wants to lose 10lb she will have to start eating less than 2000 calories per day; maybe 1500-1600 calories per day. Does this mean the serving size changes? Not necessarily. It simply means she has to decide how she wants to use her 1500 calories. Does she really like the granola and want to keep it in her diet? Or has she decided she would rather keep her bagel in her diet and that means she has to cut her granola out to hit her new calorie range. OR, maybe she still likes the granola, but doesn’t need a 1/4 cup to satisfy her. She only uses 1/8 of a cup. That is OK too! She doesn’t need to be tied down to what the label says, she has to find the serving size that works for her and her goals. This requires tracking her calories and seeing how her bodyweight and body  fat % responds.

That is what a serving size is. Food labels give you a decent starting point, but from there you have to know your goals and track your caloric intake to find what serving size is best for you.

Then what is a portion size?

This could technically also be a serving size. But, when I think of portion sizes I think of things such as a “palm size piece of lean meat,” or a “fist size of green veggies.”

Most nutrition recommendations will say a “healthy balanced meal” is something along the lines of: 1-2 palms of protein, 1-2 fists of veggies, 1-2 cupped hands of carbs, 1 thumb of healthy fat. Again, that is a good starting point! Probably a better starting point than serving sizes based off a 2000 calorie diet; especially for someone who chronically over eats and is gaining unwanted bodyfat. 

There are some issues once again though:

1. The range of “”1-2 depends on your gender. Men, should typically eat more than women. “Typically” though. If a woman who weighs 150lb is very active, exercising hard 6 days per week might need more than 1 cupped hand of carbs. If a 150lb man who sits at a desk all day and never exercises, probably doesn’t need 2 cupped hands of carbs.
2. Obviously, hand sizes are different person to person. But, were never trying to be perfect here. If you are a bigger individual and have bigger hands then you should probably be eating more than your friend who is 6 inches shorter than you and has smaller hands 🙂
3. Activity level isn’t taken into account all the time. The more active you are the more you should eat. Many portion size templates, are very general for the “average” person.

The question then becomes should you use serving sizes on nutrition labels or portion control tactics if trying to lose or maintain your weight?

I say use both. I think learning to read and interpret food labels is a crucial skill for weight loss (and long term maintenance). Many times my clients are shocked to see what a serving size of their favorite food ACTUALLY is. They may have been eating 2-3 times the recommended serving size for years. This is not saying that  1/2 cup of granola is “wrong,” when the serving size says 1/4 cup though. For me when I was trying to gain weight, 1/2 cup of granola was “my” serving size as I needed extra calories for my goal. I knew this only because I was tracking my calories though.

But, also being able to control your portion size by looking at the food on your plate is very important. Especially when eating out at restaurants and you aren’t able to weigh the chicken breast you ordered, but you can eyeball what is 4oz and what would be 10oz. Again, nutrition is not a game you need to be perfect at…if you try you will only be frustrated. Healthy, balanced and results driven nutrition plans need long term consistency over short term perfection. If you have a goal of maintaining where your current weight and body composition is, then using portion control tactics like fist size and palm size is probably your best bet to not over eat. 

A serving size of pizza is a whole pizza though, right? I think so.