All about "macros" (part 2 of 3 - protein)

Last post I explained the definition of macros and explored the complicated chemistry of carbohydrates. Miss it? ---> Click here to learn more.

This post I'll talk about everyone's favorite macro - protein. Why is it so valuable? Where does it come from? How much do you need? What's the best source? Read on to learn more. 

Remember from the first post in this series that everything in nutrition is about categories and chemistry.

Proteins are complex molecules made up of chains of amino acids (A.A.). Those amino acids are the building blocks of life and are used to: 

• Form DNA
• Create hemoglobin (the part of your red blood cells that carries oxygen)
• Build and repair muscle

• Create hormones
• Makes chemical reactions happen
• Form antibodies (the basis of the immune system)

There are 20 amino acids (the building blocks of protein) that get split into 2 categories - essential and non essential. Non-essential amino acids can be created by the body. However, essential amino acids must be obtained from food. 

Essential A.A.
​(must eat!)
phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidine

Non Essential A.A.
(body can make)
alanine, arginine, aspartic acid, asparagine, cysteine, glutamic acid, glutamine, glycine serine,proline, and tyrosine

The food groups with protein are not exclusively protein / A.A. Most contain another macronutrient such as carbohydrate or fat in addition to water. This changes the energy / calorie density of the food. 

How much protein do I need?

Research demonstrates that the human body needs .8 to 1.2 grams of protein per kilogram (OR .36 to .54 grams per pound). For a 150 lb person (68 kg), that's 54 - 81 grams of protein per day.  Protein intake beyond this has not shown to be beneficial. The extra protein will either be converted to immediate energy or excreted via the kidneys. If the body is given more energy in total from any macronutrient source (carbs, protein, or fat), it's stored for use as energy later (aka, body fat). 

Plant vs Animal Protein 

Our bodies can easily use the protein found in plant and animal foods. However, plants do not contain all of the essential amino acids (A.A.). In order to create a "complete" protein and get all of the A.A. that you need, you pair...

grain (eg, rice, oats, wheat)
nut (eg, almonds, peanuts, cashews), or
​seed (eg, sunflower, pumpkin, sesame)

+

bean (eg, chickpea, soy beans, black beans)
lentil, or
pea

Ideally the pairing is done at the same time, but the body can store and pair as the day goes on.  ​

A.A.'s aren't the only consideration when deciding whether or not to go animal or vegetable for your protein source. Calcium, iron, b12, and vitamin D are also nutrients to consider.

Animal based foods also contain a more biologically available source of iron compared to plant based foods. In order to better absorb the iron in plants, pair greens and beans with a food rich in vitamin C (most fruits / vegetables).

Blood sugar management is also a consideration for those deciding whether or not go to more plant based with their protein sources. Most plant sources of protein also contain a healthy dose of carbohydrate - which we learned in the 1st part of this series is converted to blood sugar. Additionally because vegan diets are 100% carbohydrate based, you'll likely feel hungry more often if you're not thoughtful about choosing protein and fat dense foods which slow hunger. 

Deciding whether to go with animal vs plant protein is a personal decision based upon your personal values and  health circumstances. But regardless of which way you go, don't just eat a plate of rice or pasta and call it sufficient. 

Is there such a thing as too much protein? 

Excessive protein displaces other foods in the diet which can negatively impact health. Typically when people increase their protein intake, they do it in the form of meat or protein shakes which edges out plant based foods and associated nutrients.

​Plants are amazing at disease prevention due to their high levels of fiber, antioxidants, as well as vitamins and minerals. Additionally animal based protein also tends to increase the amount of saturated fat (and often sodium) in the diet which is not awesome for our cardiovascular health. ​​

Do I need a protein shake? 

It's rare that someone "needs" a protein shake. Protein itself is not a magic bullet - by itself, it does not "create" muscle or make you bigger. What makes you gain muscle is physical activity - namely, lifting heavy things. Protein helps your muscles recover from physical activity which in turn builds muscle. But eating protein without challenging your muscles will not result in change. There's also a limit to how much protein your body can use in the repair process. More protein does not mean more muscle. If you want more details on whether or not you should consider a protein shake, check out this blog post. 

Additionally, protein supplements rarely contain the nutrients found in protein rich foods - iron, magnesium, zinc, copper to name a few. In my practice, I've found it's always better to get your protein from food rather  than supplements. 

The moral of the story...

We need protein but it's not a magic bullet. Animal protein tends to have more protein per serving BUT plants are 100% capable of providing our bodies with everything we need along with the added benefit of high levels of disease prevention. Our bodies thrive when they're fed a balanced diet based upon our physical and emotional needs. If you're trying to figure out how to make it work for you, connect with a dietitian! 

Stay nourished friends!