Proteins

Proteins are structural molecules found in every part of the body-with important metabolic functions as muscles, enzymes, hormones, transport molecules and immune factors, to name a few. Of the twenty or so amino acids that combine in multiple ways to form thousands of proteins, nine are considered essential- we must consume them from foods. The others can be made in the body from the nine essential amino acids.

The amino acids needed for human diets are found in a variety of plants and animals in abundant amounts. Whether vegan or vegetarian or omnivore, most Americans consume protein in excess of recommendations. Protein is often discussed in terms of 'quality' or completeness, with the egg and most animal proteins being considered complete (containing all essential amino acids). Soy protein and the grain quinoa are also classified as complete proteins. Yet, it is not necessary to eat all the essential amino acids or complete proteins at the same time. As long as a variety of foods are eaten over the course of a day or two, amino acid needs will be met.

Two really important protein concepts:

• Protein that we eat does NOT automatically turn into muscle tissue.
• Protein is an ENERGY macronutrient; at 4 calories per gram, it is stored as fat in the body if the energy is not needed.

What does this mean, practically? It means that consuming protein bars, powder or high amounts of protein foods will NOT make you muscular. Muscles are only formed, increased, and toned by using them. And, if there is no need for the amino acids you have consumed, the energy contained (remember, 4 kcal/gram protein) will be converted to fat for future energy storage.

Factors to consider when making protein choices- health, cost, environment

Health

Protein foods usually include other nutrients, such as fats, fiber and sodium, so our health depends on the source of the protein as much if not more than the grams of protein it supplies. Let's take a page from online retailers and choose protein sources to compare. In our imaginary web page, let's check the "compare product boxes" for 4 ounces sirloin steak, 4 ounces salmon filet, a four ounce ham steak, one cup of cooked lentils, 4 ounces skinless chicken thigh:

You might be interested to note that from a health perspective, we are less concerned about calories (they are not even listed in our chart) but we are interested in sources of protein and the type of fat they contain, the amount of sodium, and look at that- you can even get fiber from some protein sources!

Costs

Some protein foods can be quite expensive. Money-saving tips include:

• Find protein foods throughout the entire store. They can be found in the fresh meat case, frozen foods section, dairy case, and canned and pantry food aisles.
• Some great low cost choices include beans and peas, such as kidney beans, split peas, and lentils. Use these good sources of protein for main or side dishes. Beans and peas cost far less than a similar amount of other protein foods.
• To lower meat costs, buy the family-sized or value pack and freeze what you don't use. Choose lean meats like chicken or turkey. When choosing ground beef, make sure it's lean (at least 93% lean) ground beef.
• Seafood doesn’t have to be expensive. Try buying canned tuna, salmon, or sardines – they store well and are a low cost option.
• Don’t forget about eggs! They’re a great low-cost option that’s easy to prepare.
• For more tips on making healthy protein choices, check out Vary Your Protein Routine.

Source: https://www.choosemyplate.gov/tips-for-every-aisle

Environment

You may be interested in also considering the environmental "food"print of the foods you eat. In western Agriculture, animal foods generally have the highest environmental impact based on aspects including carbon emissions, land, and water.

Reference: https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/protein/