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Protein: you hear a lot about it and you know it’s important. Learn why it’s essential to good health and good eating.

What protein is and what it does

Proteins, along with fats and carbohydrates, are the macronutrients that form the basis of our diets. In our bodies proteins perform a range of duties, from building new cells to regulating metabolism to helping cells communicate. Proteins form antibodies to shuttle oxygen throughout the body in the form of hemoglobin, as well as build muscle.

Protein provides us with energy (calories). Like carbohydrates, protein contributes 4 calories per gram, versus 9 calories per gram in fats.

For many people, upping the amount of protein in the diet may help promote weight loss and improve body composition — learn more about Protein & Weight Loss.

Amino acids

Amino acids, of which there are about twenty, are the LEGOs of proteins. Our DNA directs the body to join various combinations of amino acids in a variety of sequences and three-dimensional shapes for an arsenal of about 10,000 different body proteins, each serving a unique function. Our bodies can make about 11 of these amino acids, leaving 9 that we must get from food. These remaining 9 are called essential amino acids, since it is essential that we get them from our diet.

Protein everyday

While our bodies can store fats and carbohydrates to draw on when needed, they cannot store amino acids. We need a fresh source each day in order to build the body proteins we need. If the body is missing a particular amino acid to form the protein it needs, it will pull that amino acid by breaking down existing muscle protein. If we consistently lack protein we lose muscle weight, energy and, eventually, fundamental functions. For an estimate of how much protein you should be getting each day see our Protein Calculator.

Think you’re not getting enough protein? Find 10 Ways to Eat More Protein.

Protein sources

Many foods contain protein in some form. Here are the main sources of dietary protein:

  • Meat, poultry, eggs, dairy, and fish are complete sources of protein because they contain all 9 essential amino acids. Some animal protein sources—most notably red meat and whole dairy products—can also be high in saturated fat, which can raise cholesterol levels. Learn more about lean sources of animal-based protein.
  • Soy, often in the form of tofu, or soy milk, is a popular plant-based source of protein since it, like animal-based protein, contains all 9 essential amino.
  • Nuts, seeds, beans, peas, and whole grains can be terrific sources of protein. One thing to keep in mind with plant sources of protein, is that not all plant proteins are equal. With the exception of soy and quinoa, plant foods don’t contain all 9 essential amino acids. But certain plant foods complement each other with their amino acid profiles. For example, beans tend to be low in one amino acid that grains have plenty of, so combining these foods forms a complete protein. Learn more about complete plant proteins and vegetarians and protein.

Find out just how much protein different foods contain with our Guide to Protein Sources.


  Other ways to learn more about protein  

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  1. 48_photo_63

  2. User_48
    ltco commented on this. about 2 years ago

    I just was diagnosed with diabetes. what about the carbs? I know nothing about nutrition .I just know I am supposed to watch my carbs. Judi

    1. 48_smiley
      AngryGood over 1 year ago

      Not just any carbs; just simple carbs like sugar and starches. Fiber is a carbohydrate too, but those are good and you can have lots of it.

  3. User_48
    weymouthbob53 commented on this. about 2 years ago

    how about a lower sugar granola bar

  4. User_48
    edujbald commented on this. over 2 years ago

    Individuals with thyroid issues also need to stay away from soy products as it blocks the absorption of your thyroid medication. Its amazing how many foods now have soy in them that you wouldn’t expect. I have become a very careful label reader after getting sick from too much soy before finding out that soy and an underactive tyroid do not mix.

  5. User_48
    kashi_m commented on this. over 2 years ago

    There is a delicious PROTEIN SHAKE that I use in between meals, or after a workout. It is a whey protein (from milk so it can help with relieving the stress off muscles after a workout.

    The shake is from Vitamin Shoppe and its called Elite, from the Brand Dynamite. Very low in calories, no sugar, and good amount of protein. Try it cold or with fruit.

  6. User_48
    kfetsko commented on this. about 3 years ago

    Everytime I eat anything with high soy content, like soy beans, soy nuts, soymilk or edemame. I get a stomach ache or an upset stomach. But if something has a small amount like a granola bar that conatins soy lecithan it doesnt bother me. I dont know why, its just me. So I try to get protein from other sources. Such as from nuts, fish, chicken, turkey, and lowfat dairy products “as log as I take a lactiade with dairy”. So you definiatly dont need soy to get lean souces of protien. But if you like soy and it doesnt bother you, go ahead eat it.

  7. User_48
    sunflower64 commented on this. over 3 years ago

    I love the vive cold cereal with vanilla soy, whats wrong with soy milk. I cant use regular milk, but I also like rice milk would that be a better choice?

  8. User_48
    Nan52 commented on this. over 3 years ago

    I’m currently doing the Nutrisystem Diet. But, I’m concerened about the high levels of soy product in their food. I have Hashimotos Disease and need to avoid too much soy. I’m wondering what percentage of soy product is in Kashi food? Anyone know, or can give me a tip on how to figure that out?

  9. 48_tammi
    tammi42065 commented on this. over 3 years ago

    Interesting information. I would have like to see a breakdown of the amount of protein contained in each individual food to help really guide me to the most beneficial foods for me.

  10. User_48
    FLlifter commented on this. almost 4 years ago

    PLEASE be aware that soy is NOT good for you. It contains so many toxins its ridiculous.

  11. User_48
    Nellma47 commented on this. over 4 years ago

    Thanks for the information becasue I was wondering how much protein I need a day to be healthy.