Protein 101: The Complete Guide for Beginners
In this guide, we’ll take a deeper dive into protein. You’ll learn why you need it, how much protein you should be eating each day for optimal health, the different sources of protein (plant vs. animal), how much you can absorb in a single meal, the best time to eat it, and more.
Click the links below to explore the different sections of this article:
- What is protein?
- Why do our bodies need protein?
- What are the benefits of protein?
- What foods are high in protein?
- What’s the difference between plant vs. animal sources of protein?
- How much protein do you need each day?
- How much protein can you absorb each meal?
- Is there an ideal time of day to eat protein?
- Is there such a thing as too much protein?
- What are the side effects of eating protein?
- How do you get more protein in your diet?
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What is protein?
The foods we eat contain three macronutrients: protein, fat, and carbohydrates. Proteins are organic molecules made up of amino acids.
Nine of these amino acids—histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine—are called the essential amino acids.
Branched chain amino acids (BCAAs) refer to the three essential amino acids isoleucine, leucine, and valine. They play an important role in the regulation of muscle mass and are one of the reasons that proteins are considered the “building blocks” of life.
Why do our bodies need protein?
More than 10,000 types of protein are found in your organs, muscles, tissues, bones, skin, and hair. In fact, every cell in the human body contains protein.
You need protein in your diet to help your body repair cells and make new ones.
Protein also helps provide energy and helps your blood carry oxygen throughout your body. And, it helps create antibodies that fight off infections.
What are the benefits of protein?
Protein has a number of known functional benefits. It plays a role in:
- Growing and repairing tissue (including muscle hypertrophy).
- Cellular communication to help your body fight off infections.
- Turning food into energy.
- Supporting bone and brain health.
- Providing essential amino acids that assist with vitamin absorption, energy production, and protection against viruses and bacteria.
- Helping manage your weight.
What foods are high in protein?
Here’s a list of high protein foods:
| Food: | Grams of Protein: |
| Almond butter | 9 grams per 1/4 cup |
| Artichoke | 4 grams per artichoke |
| Avocado | 3 grams per avocado |
| Beans (Black, Pinto, Navy, Lima, Garbanzo) | 8-10 grams per 1/2 cup |
| Beans (Refried) | 7 grams per 1/2 cup |
| Beef | 22 grams per 3 oz. |
| Broccoli | 2 grams per cup |
| Cheddar cheese | 8 grams per 1/4 cup |
| Chicken breast | 19 grams per 1/2 cup |
| Cottage cheese | 12 grams per 1/2 cup |
| Eggs | 6 grams per egg |
| Goat cheese | 8 grams per 1/4 cup |
| Lentils | 9 grams per 1/2 cup |
| Milk | 7 grams per 8 oz. |
| Oatmeal | 3 grams per cup |
| Pork | 23 grams per 3 oz. |
| Pumpkin seeds | 10 grams per 1/4 cup |
| Quinoa | 4 grams per 1/2 cup |
| Salmon | 17 grams per 3 oz. |
| Tuna | 24 grams per 3 oz. |
| Whole wheat pasta | 4 grams per 1/2 cup |
Read More:
Protein Content in Common Foods – Johns Hopkins Medicine
High Protein Food List – HealthBeet.org
What’s the difference between plant vs. animal sources of protein?
Our bodies create 11 of the aforementioned amino acids. These are called “non-essential amino acids”. We need to get the other 9 essential amino acids from food.
Pros and Cons of Animal Based Proteins
Animal proteins, which include milk, eggs, and meat, are considered complete proteins, which means they contain all of the 9 essential amino acids. This is important because complete protein sources such as those that come from meat may be better for muscle growth and maintenance compared to single-source plant proteins.
However, eating too much animal protein may have some serious drawbacks.
Several studies have linked red meat consumption to an increased risk of heart disease, stroke, and early death. The scientists who author these studies advise limiting your intake of processed meats like smoked meats, sausage, hot dogs, salami, and bacon.
Pros and Cons of Plant Based Proteins
Now let’s talk plant based protein. Certain plant proteins (quinoa, for example) are considered complete proteins. But most plant-based foods are lacking one or more of the 9 essential amino acids, so it’s important to eat a variety of nutrient-rich foods if you’re following a plant-based diet.
Studies show that those on vegetarian or vegan diets have a lower risk of developing certain diseases including cancers, type 2 diabetes, hypertension, obesity, and heart disease.
Read More:
Benefits of Protein Powder: Plant Vs. Animal Sources
How much protein do you need each day?
The current recommendation based on the 2020 – 2025 Dietary Guidelines and National Academy of Medicine for protein intake is 0.8 g/kg (or around 0.36 g/lb) of body mass in generally healthy adults– around 50 grams per day.
However, according to a 2019 paper published in the journal Nutrients:
The current protein RDA … is often incorrectly applied when used as the definition of recommended intake, rather than its true designation as the required minimum intake.
In other words, 50 grams per day should not be viewed as the optimal amount; rather, it should be the bare minimum.
To improve or maintain your current body composition (build or maintain muscle and/or lose weight), aim for at least:
- 1.2 – 1.8 grams per kilogram of body weight (or 1 gram per pound if you’re an older adult, avid exerciser, and/or want to lose weight)
- 30-40 grams of protein each meal spread out every 3-4 hours
Read More:
How Much Protein Do You Need Each Day
How much protein can you absorb each meal?
A 2018 study from Brad Schoenfeld and Alan Aragon published in the Journal of the International Society of Sports Nutrition found that 0.55 g/kg/meal is the upper limit most people can absorb, which translates to 35-45 grams of protein for the average person per meal.
Is there an ideal time of day to eat protein?
You may have heard that before or after a workout is the best time of day to eat protein. However, the jury is still out on this one.
In a 2013 study, researchers said:
Despite claims that immediate post-exercise nutritional intake is essential to maximize hypertrophic gains, evidence-based support for such an “anabolic window of opportunity” is far from definitive.
In contrast, the current position of the International Society of Sports Nutrition (ISSN) is the following:
Post-exercise ingestion (immediately to 2-hours post) of high-quality protein sources stimulates robust increases in muscle protein synthesis (MPS).
In other words, there may be benefits to consuming your protein within 2 hours post-workout.
What’s most important though is meeting your total daily intake of protein, preferably with evenly spaced protein feedings (approximately every 3 hours during the day).
Is there such thing as too much protein?
People that eat high protein diets have a higher risk of kidney stones and other kidney issues, so those with pre-existing kidney conditions should talk to their doctors before starting a high protein diet.
Also, diets that contain large amounts of red meat might lead to a increased risk of heart disease and colon cancer.
What are the side effects of eating protein?
The body can’t store protein, so once its protein needs are met, any extra is used for energy or stored as fat. Excess calories from any source will be stored as fat in the body.
So if you significantly increase your protein intake without decreasing your intake of fat and carbohydrates, it could lead to weight gain.
The problem with limiting other macronutrients like carbohydrates though is you might not get enough essential nutrients like fiber, which can cause side effects like constipation, bad breath, and headache.
“Carnivore diets” high in meat may increase your low-density lipoprotein cholesterol (LDL) levels and put you at increased risk for heart disease.
High protein diets may affect kidney function in people with kidney disease.
How do you get more protein in your diet?
To get more protein in your daily diet, there are several strategies you can use:
- Track how much protein you’re eating using a food tracker or app.
- Plan ahead and cook your own meals.
- Aim for 30-40 grams of protein per meal.
- Try supplementing with protein powder.
Different Types of Plant Vs. Animal Protein Powder
There are many different types of both animal and plant-based protein powders. Here are some of the most common:
Common Types of Plant Protein Powders
- Plant
- Pea
- Rice
- Hemp
- Pumpkin
- Chia
- Soy
- Algae
- Bean
Just remember if you’re using a vegan or plant-based protein powder, you should combine several different types to get a complete amino acid profile (or look for a plant protein powder that contains 3-4 different sources of protein).
Common Types of Animal Protein Powders
- Whey
- Casein
- Milk
- Egg
- Collagen
Regardless of whether you choose an animal or vegan source of protein powder, make sure you’re choosing a product without added sugar and other unnecessary junk. Generally speaking, the fewer ingredients, the better.
Read More:
How to Get More Protein in Your Diet (Without Fat, Sugar, or Carbs)
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