You know that protein is an important part of your diet, but which protein is best for you? Red meat? Fish? Whey? Soy?
Traditionally, when we think of our bodies using protein, we think of bulging muscles – but building muscle is not everything protein can do!
Proteins make up around 17% of your body. The walls of cells, the machinery inside them, the neurons in your brain – these are all made of protein, and they all need to be built in a very specific way. Even your DNA is made from recycled protein!
Athletes have been eating high-protein diets for thousands of years. Recently, production of powdered whey protein (pioneered by Frank Thomas in the 1970s) has led to the invention of infant formula, protein fortification of baked goods, and the development of protein powders.
The supplementation of athletes’ diets with extra protein is an area of great debate – experts and athletes alike question which proteins are best, why, and for whom.[Tweet “Turns out professional athletes are right – eggs and whey are some of the best sources of protein.”]
The Institute of Medicine recommends that men eat 1.98oz / 56g of protein per day, while women should eat 1.62oz / 46g. That protein should make up 10-35% of your daily calories. This figure refers only to the pure protein in any whole food.
If you are extremely active or do intense training, you may want to increase this amount either by eating more protein based foods or supplementing with purified protein powder. Don’t overdo it, though. Too much protein can cause bone health problems and renal function issues.
- Which protein-based foods fit within your chosen diet?
- Which protein-based foods fit within your lifestyle, and activity levels?
- Which protein does your body tolerate well?
What is protein? Breaking it down.
“It helps to understand that protein is a macronutrient. What we call “protein” is, in fact, a family of amino acid molecules. When grouped together in various combinations we get proteins. There’s no protein molecule hanging out in that hamburger; rather, the animal tissue is made of many different amino acid building blocks. Protein is just a catch-all term we use.” – Mark Sisson, author of The Primal Blueprint
– Essential: our bodies cannot make amino acids, meaning we must consume them. There are nine for humans: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
– Non-essential: your body can make these from other amino acids and molecules.
More than 90% of amino acids are recycled into other proteins.
The remainder are broken down into urea and excreted as urine, or they are used to make important molecules. These include heme (the part of hemoglobin that carries oxygen in the blood), creatine (which helps supply energy to muscles), hormones, and nucleotides (which make up DNA).
Every day, your body breaks down around 9oz / 250g of protein in a process called ‘protein turnover’, and 9oz is remade from the available amino acids in your blood. Unlike glycogen storage of glucose or fat storage of triglycerides, the body does not allow for the storage of amino acids.
This means that eating high-quality protein to replenish this pool is vital.
Otherwise, the body maintains the supply by destroying other tissues (especially muscle), which is not what you want at all!
What makes a ‘good’ protein?
“The primary difference between animal and plant proteins is their amino acid profiles and it is those profiles that direct the rates at which the absorbed amino acids are put to use within the body. ‘Substrate’ amino acids derived from animal based proteins are more readily available for our own protein synthesizing reactions which allows them to operate at full tilt. Plant proteins are somewhat compromised by their limitation of one or more amino acids.”
T Colin Campbell, PhD, author of The China Study
Basically, all animal protein is considered ‘complete’, meaning it contains all the essential amino acids, whereas most vegetable proteins usually lack one or more.
There are exceptions though – soy, quinoa, buckwheat and hemp all have a complete array of amino acids and are relatively high in protein. As such, they are great for you!
Which protein is BEST?
Let’s start with what we mean by ‘the best’.
-the composition and completeness (variety of essential vs. non-essential)
-digestibility (breakdown and absorption)
-bioavailability (able to be used by your body)
There are several ranking systems, but the two main ones are Biological Value (BV) and the Protein Digestibility Corrected Amino Acid Score (PDCAAS). These systems are currently considered to be the most thorough and reliable comparisons of protein quality for human nutrition.
BV measures how efficiently protein is used by looking at how much protein is absorbed compared to how much ends up being used.
Since the value is calculated relative to a whole egg (which has a BV score of 100 and is normally considered the best whole food protein source), it is possible for processed proteins like whey to score higher in this system.
The Food and Agriculture Organization (FAO) and World Health Organization (WHO) developed the PDCAAS, which shows a protein’s value in human nutrition. It measures quality based on composition and digestibility.
Ingesting high quality protein is most important when your body is using amino acids rapidly, including those times during muscle building and recovery after an intense workout, during cell reparation when you’re ill, and during pregnancy, growth spurts or bulking.
Throughout these periods, you’ll want to look for a quickly digestible, complete protein with a high BV and PDCAAS value and a higher percentage of protein per serving.
Let’s compare beef with tofu so you can see how this works:
Beef 3oz / 85g 215cal 0.77oz / 22g protein (26%) 17.6
Tofu 3oz / 85g 65cal 0.25oz / 7g protein (10%) 4.5
As you can see, tofu has ⅓ the protein density of beef. This means you need to eat more than three servings to get the same amount of protein and calories.
The other major consideration is the makeup of the remaining non-protein portion of the food. This influences the time it takes to absorb amino acids, as well as the energy, fat and nutrient content.
The body digests vegetables and pure protein in shakes quickly, for example, whereas it breaks down meat’s collagen fibers more slowly. Vegetables and fruits have somewhat slow-digesting fiber, but they also contain quick-burning sugars.
When digested, your brain reacts to the increase in peptides by sending satiety signals. This means a protein-dense meal keeps you feeling full for longer periods of time.
Ok, what should I eat?
- fit within your chosen diet (Paleo, vegan, etc).
- work for your body (Allergies? Lactose intolerance?).
- have a high PDCAAS, indicating high quality and completeness.
- have a high BV, ensuring your body uses as much of the protein as possible.
- are affordable. Not everyone can buy steak or expensive protein powders regularly.
So what does that mean?
After crunching the data, we can see that professional athletes are right – eggs and whey are some of the best sources of protein. Soy is a fantastic non-meat source, and there are some other surprise contenders, including spirulina and quinoa, which you may want to consider adding to your diet.
Some foods are considered ‘complete’ in certain combinations – soy sauce adds needed lysine to seitan, for example. Most beans are low in methionine and high in lysine, while rice is low in lysine and high in methionine – but together, they’re a vegan protein powerhouse.
As you can see, there’s no golden ticket for The Best Protein Ever.
There are, however, many foods that provide complete protein in high concentrations in a way your body can easily use.
Here at Factor, we emphasize protein choices of meat, fish, poultry and eggs, and prioritize local pasture-raised, certified organic products. Now that you know how to determine which proteins are ‘better’, you can determine which are ‘best’ – for you.