Protein. All you need to know.


Protein is one of the most common and often asked topics. There are many questions: what are they? How much do I need? What are the best sources of protein? Do I need protein shakes? and many more.
Today I hope to solve all (or most) of the questions you may have about protein because the sooner you understand how it works and why you should pay attention to it, the sooner you will see the results of your efforts.
In this article, I have gathered some of the most acute questions that I have been asked on many occasions, so I think that you may be asking yourself too.

What are proteins and what do they do?

The word protein comes from the Greek “proteos”, which means “primary” or “first place”. This gives you an idea of how important proteins are. They are complex molecules made of smaller units called amino acids and play several fundamental roles: structure, function, and regulation of the body’s tissues and organs.
Proteins can be classified based on their shape, whether or not they dissolve in water, by what they do, or in lots of other ways. One of the easiest ways is by function, on what they do:
  • Antibodies: fight foreign particles protecting your body. Immunoglobulin is a large, Y-shaped protein used by the immune system to identify and neutralize pathogenic bacteria and viruses.
  • Enzymes: carry out almost all of the chemical reactions that take place in cells, and assist with the creation of new molecules. They are like little machines. Some of them build bigger molecules from smaller blocks, others break bigger molecules down into smaller parts. Whether building or breaking, most enzymes can do this 50 to 5k times per second. Your body makes many different kinds of enzymes to digest the food you eat into molecules that your cells can use. Amylase is a good example. It´s an enzyme made by your saliva glands to help break starch down into sugar. Try this experiment: put a cracker on your tongue and wait. At first, the cracker tastes salty but as your mouth waters, the amylase will start to turn the starch in the cracker into sugar, making it taste sweet. 
  • Messengers: such as some types of hormones, transmit signals to coordinate processes between cells, tissues, and organs. Adrenaline is a hormone that regulates visceral functions (e.g, respiration). It plays an important role in the famous fight-or-flight response, increases blood flow to muscles, the output of the heart, pupil dilation response, and blood sugar level.
  • Structural components: provide structure and support to your cells. On a larger scale, they allow the body to move. Collagen is a perfect example. It holds different parts of your body together connecting and supporting your muscles, bones, tendons, ligaments, cartilage and even holds your skin together. You can find a great article about collagen at Mind Body Fit
  • Transport/storage: bind and carry small molecules and atoms within cells and throughout the body. Hemoglobin carries oxygen from your lungs to every single cell in your body.

Combining these amino acids we get all these different kinds of proteins?

Exactly, 21 different types of amino acids can be combined to make a protein. The sequence of amino acids determines each protein’s unique structure and function.
Think of amino acids like Lego pieces. The amino acids (Lego bricks) are connected into long chains to build different proteins. Some chains fold into spirals. Other chains make zigzag sheets and loops.
Combining these spirals, sheets, and loops is how the three-dimensional shape of the protein is made. You can also combine multiple chains of amino acids to make even bigger protein shapes. Because amino acids can be arranged in many different combinations, your body can make all the proteins it needs to function and grow from just the same 21 amino acids.
How many things can you build with 21 different Lego bricks? There are so many possibilities! 

Where do these amino acid building blocks come from?

Your body can make most of the amino acids it needs from other molecules already present in your body. For instance, your body can take apart the amino acid building blocks that make one protein and re-use these to make new, totally different proteins. But nine of these 21 amino acids can’t be made this way, your body can´t synthesize them so you have to get these amino acids from the food you eat. These are the essential amino acids: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
You find them in milk, eggs and meat, and a wide variety of plants. This is why you can’t survive on a mono-diet for very long. A mono diet is a simple eating pattern that involves eating just one food item or food group for all meals throughout the day. This is too restrictive, unsustainable, and unhealthy.
In fact, essential amino acids were discovered in an experiment testing a mono diet. Scientists fed rats a diet that had only corn protein. They noticed that rats on this diet got sick and would eventually die. When the sick rats were fed protein from milk, however, they would get better. This told the scientists that something in milk protein was essential to the health of rats, that it was something they couldn’t live without, essential amino acids.

How much protein do I need?

The recommended daily amount of protein for adults is calculated based on your body weight. The National Academy of Medicine recommends that adults get 0.8 grams of protein for every kilogram of body weight per day to maintain muscle mass. 2 grams of protein for every kilogram of body weight per day to gain muscle.
You weigh 70 kg, which means about 56 grams of protein each day to maintain and 140 grams to gain muscle. This amount of protein intake should mean between 10% to 35% of your total daily calories. However, the ideal amount of daily protein that you should consume varies depending on a number of factors: age, gender, activity, health, and other variables.
Most people can easily meet this goal with no supplements, just from food. But foods contain a lot more than protein (fats, fiber, sodium, and more). So it’s important to pay attention to what else is coming with it.
A few examples:
  • A 4-ounce broiled sirloin steak brings about 33 grams of protein. But also about 5 grams of saturated fat.
  • A 4-ounce ham steak, 22 grams of protein, only 1.6 grams of saturated fat, but it’s loaded with 1,500 milligrams of sodium.
  • 4 ounces of grilled sockeye salmon has about 30 grams of protein, it´s low in sodium, and contains just 1 gram of saturated fat.
  • A cup of lentils provides 18 grams of protein and 15 grams of fiber, and it has no saturated fat or sodium.

What are the best sources of protein?

Both plants and animals are good sources of protein. According to the Food and Nutrition Board of the Institute of Medicine, meat, poultry, fish, eggs, milk, cheese, yogurt, quinoa, and soybeans are all sources of complete protein, they provide all the essential amino acids. We call them complete protein sources. It’s important to notice that many plants do not provide all of the essential amino acids, they lack one or more of them. This should not discourage you if you want to go vegan, just be careful and eat a wide variety of vegetables to ensure that you get all of the essential amino acids.
On the other hand, if you eat meat, you should also eat veggies.
Some tips for shaping your diet with the best protein choices:
  • Get protein from plants: legumes, nuts, seeds, whole grains, and fruits.
  • Poultry, fish, and seafood are better options than red meat. You should eat red meat in small amounts or on special occasions. Processed meats (bacon, hot dogs, sausages, and cold cuts) should be avoided.
  • Eggs are a great and cheap choice.
  • Dairy in moderation (1-2 servings a day).
Vegetarians can get a complete protein with combinations such as:
  • Grains and legumes: rice with lentils or pasta salad with kidney beans.
  • Grains and eggs: egg-salad sandwich on whole-grain bread.
  • Legumes and seeds: hummus and sesame seed paste.
  • Grains and dairy: grilled cheese on whole-wheat bread.

Do I need protein shakes?

Protein shakes are very popular. However, most people can get all the protein they need from food. And the food you eat also provides other essential nutrients.
A protein supplement is a good idea if you struggle to reach your protein goals. If you’re already eating plenty of high-quality protein food, the benefits of adding protein shakes will probably be minimal. If your protein intake is high, protein shakes are completely unnecessary. But these shakes can be a convenient way to replace some meals.
There is a wide variety of protein shakes: whey, casein, soy, egg. It´s a complete field to study in-depth, so I´ll give you some basic guidelines.
The protein in cow’s milk is 80% casein and 20% whey. Whey is the liquid part of milk left behind during the production of cheese. Have you ever opened a yogurt container and seen liquid floating on top? That’s whey. It contains all essential amino acids. There is evidence that whey protein is better absorbed than casein or soy protein. People with lactose intolerance need to be careful, and some people may even be allergic to it.
Whey protein usually comes in three major forms:
  • Concentrates: have typically about 70–80% protein; contains some lactose (milk sugar), low level of fat and cholesterol. Whey protein doesn’t taste very good so it’s usually flavored. Chocolate-, vanilla- and strawberry-flavored powders are popular. But my favorite is Cookies!
  • Isolate: are processed to remove the fat and lactose. They contain 90% (or higher) protein by weight.
  • Hydrolysates: are predigested and partially hydrolyzed for easier absorption. Hydrolysates cause a 28–43% greater spike in insulin levels than isolates.

Why everybody takes protein shakes after a workout?

The idea is to facilitate the muscular repair and enhance post-exercise strength- and hypertrophy-related adaptations. The effectiveness of this habit in 47 scientific studies has not been proved. Studies showed a small to moderate effect on muscle hypertrophy with no significant effect found on muscle strength. These results refute the belief that the timing of protein intake in and around a training session is critical to muscular adaptations and indicate that consuming adequate protein throughout the day is the key factor for maximizing muscle growth. You should eat protein in every meal. A protein shake after your workout won´t make miracles.   

How much protein can the body use in a single meal?

On rare occasions, you can find where it all began. This is one of these rare occasions. The first study that tried to find out how much protein can you use in a single meal was “Timing and distribution of protein ingestion“… Areta et al. This study concludes that muscle protein synthesis is maximized in young adults with an intake of ~ 20–25 g every 3 hours. Anything above this amount is believed to be oxidized for energy or to form other compounds.
This trial provided differing amounts of protein to resistance-trained subjects over a 12-h recovery period following an exercise protocol. A total of 80 g of whey protein was ingested in one of the following three conditions:
  • 8 servings of 10 g every 1.5 h
  • 4 servings of 20 g every 3 h or
  • 2 servings of 40 g every 6 h
Results showed that muscle protein synthesis was greatest in those who consumed 4 servings of 20 g of protein, suggesting no additional benefit, and actually a lower rise in muscle protein synthesis when consuming the higher dosage (40 g) under the conditions imposed in the study.
In all honesty, this study shows some limitations like the composition of the given protein source, the composition of the meal, the amount of protein ingested, and the specifics of the exercise routine. Further investigations have been made trying to find a higher anabolic ceiling and scientists are still speculating on this point.

Can I help my body absorb more protein?

There are few ways to improve the protein absorption process.
  1. Complex carbohydrates: When you consume carbohydrates, your body releases insulin which helps your muscles absorb amino acids. Eating carbohydrates before a workout yields the best protein-absorbing results. Starchy food, whole grains, nuts, seeds, and dairy products contain complex carbohydrates.
  2. Papaya, pineapple, or kiwi as dessert: These three fruits contain enzymes that help to break down protein molecules into amino acids.
  3. Acidic Foods: These contain proteases that can make your stomach a more acidic environment for breaking down protein.
  4. Vitamin B-6: Its primary purpose is to help enzymes break down protein and carry the dismantled amino acids to the bloodstream. 
Now you know a bit more about protein, you can calculate how much you need on a daily basis, where to get it from, how your body processes it, and why protein is so important for your health. Have you got any other questions about protein? Let me know in the comments.

Are you on the list?

+14.000 members are getting +20 years of fitness & nutrition experience and exclusive content in their inboxes… for FREE.

Join us! 

Like this:

Like Loading...

Rest 30 seconds


Rest 40 seconds


Rest 60 seconds


Rest 90 seconds


Rest 120 seconds

%d bloggers like this: