What Is High-Quality Protein?

What is high-quality protein?

Being able to answer this question is important because eating high-quality protein at every meal is a cornerstone of good nutrition. When you plan meals around high-quality protein, you have better body composition and tend to be leaner than if you had a lower protein intake. In addition to dampening hunger, proteins stimulate protein synthesis, helping your body build muscle instead of storing fat.

The benefits of high-quality protein don’t stop there. Significant research shows high-quality proteins are best for:

Optimizing bone health.

Protecting of your metabolism by balancing blood sugar.

Keeping cognition cranking and mood steady.

Supporting cardiovascular health and blood pressure regulation.

Accelerating recovery from injury or intense, muscle-damaging exercise.

What Is High-Quality Protein?

With the popularity of plant-based diets, there is confusion about the definition of high-quality protein. It’s common for people to proclaim quinoa, chia seeds, or even brussels sprouts as high-quality protein foods. While these are delicious and healthy foods that have many redeeming qualities, they should not be confused as high-quality proteins.

The difference between animal and plant-based proteins is in the number and type of amino acids they contain. High-quality proteins contain all the essential amino acids. These are amino acids that your body must get from food. It can’t manufacture them from raw materials inside the body.

The essential amino acids are:

1. Leucine
2. Isoleucine
3. Valine
4. Threonine
5. Histidine
6. Lysine
7. Methionine
8. Phenylalanine
9. Tryptophan

Foods that contain all the essential amino acids are called complete proteins. They include animal proteins, such as meat, seafood, poultry, eggs, and other dairy products. Soy and pea protein also contain all nine essential amino acids, though they aren't as effective for building muscle as animal-based proteins like whey protein (1, 2).

One reason plant-based proteins aren’t as useful muscle building is that you will be hard pressed to get optimal amounts of the amino acid leucine from plant proteins. Leucine is the strongest stimulator of protein synthesis. Along with the other branched-chain amino acids (BCAAs) isoleucine and valine, it has a powerful impact on energy levels. Seeds, soy, and some vegetables like watercress contain leucine, but the concentration is small compared to whey protein or eggs.

What Are Good Plant-Based Protein Sources?

Soy and pea protein top the list of high-quality protein sources. Both clock in as “complete” protein foods containing all nine essential amino acids. However, there are some drawbacks to both. For example, soy protein contains phytoestrogens that can bind with hormone receptors. When this happens, you affect hormone balance, which is generally not something you want to do.

Additionally, plant-based proteins have lower digestible value. Digestible value refers to how effectively your body breaks down the protein you eat. Protein digestibility scores are usually measured out of 100 percent. If a digestibility score is 80 percent, then for every 10 grams of protein you consume the body will only absorb 8 grams. Eggs, milk, and whey protein have digestibility scores of 100 percent, whereas beef is 92 percent, soy is 91 percent and pea protein is 67 percent (3).

Chick peas, lentils, kidney beans, barley, and oats all clock in between 50 and 70 percent digestibility, whereas wheat is 46 percent (3).

In practical terms this means that the body can’t use vegetable-derived protein sources from plants as efficiently as animal proteins. You may need a higher total protein intake to achieve the same physiological effects with plant proteins as with animal proteins. This can be doable. But it takes some planning and can be a drawback for people who are counting calories to manage body weight because eating more is generally not the goal.

High-Quality Protein Recommendations

With the drawbacks of relying on plant-based proteins, it’s recommended that you plan your meals to include high-quality animal protein. Chicken, turkey slices, salmon, cod, beef, pork, yogurt, milk, bison, whey protein, and wild meats are all great protein sources to include along with healthy fat and fibrous vegetables at every meal.

This sets you on your way to achieving two of the most important factors for optimizing protein intake:

1. Total protein intake over the course of the day
2. Reaching a threshold dose of protein per meal for maximal protein synthesis

Studies recommend a minimum total protein intake of 1.6 g/kg (0.73 g/pound) of protein over the course of the day for maximal protein synthesis. For a 160-pound person this equals 116 grams of protein. Athletes and people involved in resistance training may benefit from going as high as 2.4 g/kg/day.

A threshold dose of 20 grams per meal is necessary for younger adults. Older adults (over age 50) suffer from something known as “anabolic resistance,” which means that they need more protein per meal to maximize protein synthesis. Scientists recommend a minimum of 28 grams for a 160-pound adult.

What Do You Do If You’re A Vegetarian?

The key to nutrition success as a vegetarian is planning. It’s completely possible for plant-based eaters to get sufficient protein and other key nutrients that are deficient in plant proteins like zinc, iron, omega-3 fats, creatine, and vitamin B12 but it requires a bit of effort.

In setting your protein goals, you will likely need more total protein than omnivores because the body can’t use vegetable-derived protein sources as efficiently. Bump up your daily total protein goal if you’re getting your protein from vegetarian sources.

Here are other suggestions for meeting specific nutrient needs on a plant-based diets:

Supplement with vitamin B12 and a vegetarian source of omega-3 fats from microalgae.

Improve absorption of iron and zinc by soaking beans, grains, and seeds prior to eating them.

Supplement with creatine and BCAAs or leucine to optimize muscle repair and performance.

Final Words:

Including high-quality protein is an easy way to manage hunger while getting great nutrition with minimal supplementation. Animal proteins contain the array of essential amino acids your body requires from food. They also provide the key brain and performance nutrients like creatine, vitamin B12, and iron. Including vegetarian proteins is good too: These can be used as condiments, adding texture and flavor to meals while padding your amino acid profile for an even better protein intake.