Tuesday, August 26, 2008

Would you like a protein with that?

From Wikipedia.com, this is a 3D representation of "a protein."

Struggling to get caught up on work after a week's vacation, I haven't posted regularly lately. Sorry. But today I had to fire up the blogger to vent about something that really irks me, which is the misuse of the term "protein." It seems that most people's minds are perfectly programmed to regard food in such a way that they need to have a chunk of "protein" at every meal (particularly dinner). For example: "Ok, I have a vegetable and a starch, and now I need a protein." Or, worse (Mother to school-age child): "No, you can't have a banana, I want you to have a PROTEIN now." I see this time and time again as a dietitian and mom: parents flip out if their kid has a meal without a concentrated protein source. I've seen more than one mom force feed their child a McDonald's burger (sans bun) or slab of cheese. Not because the child is enjoying it but because the mothers actually believe that they are doing their children a favor.

For optimal nutrition, humans need approximately 10%-15% of their calories from protein. For an average 2000 calorie diet, this means about 200 calories from protein, or about 50 grams. It would be a challenge to eat even a marginally healthy diet and NOT reach this level. Most Americans eat double, triple, even quadruple this amount -- and we see a concomitant increase in heart disease, kidney disease, and bone disease.

People ask me all the time, "Where do you get your protein?" It is a reasonable question, because Americans have been brainwashed to believe that meat = protein and plants = not protein. But this myth needs some serious shattering.

Keeping in mind that our food should average about 10-15 percent of its calories from protein (a good goal is around 12%; those with higher protein needs, such as athletes should aim higher), consider the following foods and their respective percent protein contents:

broccoli: 43% protein
whole wheat bread: 16% protein
tomatoes: 12% protein
mushrooms: 21% protein
chick peas: 22% protein
lentils: 31% protein
tofu: 43% protein
string beans: 22% protein
bagel (white!): 15%

Source: Nutribase Software, and The Dietitian's Guide to Vegetarian Diets: Issues and Applications, by Virginia Messina, Reed Mangels, and Mark Messina, 2004.

Again, these numbers represent the amount of protein as a percentage of calories, not as a percentage of weight or volume. Since most vegetables have relatively few calories, small servings obviously have little total protein. So you'll need to eat a lot of vegetables to get a lot of protein, but of course no one is recommending that you eat only vegetables. The point is that if you eat enough calories from a variety of plant foods, your protein needs will most likely be met. Remember, you only need 10-15% protein, so eating an appropriate amount of calories from a variety of vegetables and other whole plant foods will supply plenty of protein, and a healthy balance of nutrition.

See, even a vegan can have too much protein! But round these foods out with healthful lower protein foods such as fruits, and you've got a balanced, health-supporting diet.

1 comment:

Peace_7272 said...

This is VERY helpful! I've been confused before about whether I should make a specific effort to eat protein at every meal and it is a relief to see how much protein so many non-animal foods really have. Thanks!