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Amino what? Amino acids.

Don’t let the title of this article keep you from reading. Your (optimal) health may depend on it. You need to know about amino acids.

I saw the power of protein and amino acids firsthand, as my personal training clients got leaner, felt better, and improved their health and fitness by starting with a single focus of increasing their protein or amino acid intake. The more I saw them getting results, the more fascinated I became with protein and amino acids.

I realize that most people won’t feel that same level of excitement — but I suggest you read this entire article anyway. Once you realize how powerful protein and amino acids are, you won’t look at your meal choices the same way again.

You also might be motivated to make an amino acid supplement one of your core nutritional supplements, especially if you’re older than the age of 30.

Throughout this article, I address the following questions: What are amino acids? What are amino acids good for? Why are they so important to your health and fitness? Why are they so important as you age?

Protein and Your Body

Your body is about 60 percent water. Remove all the water, and almost half of what’s left will be protein. Amino acids are the building blocks of protein.

Every day, about 250 to 300 grams of the protein that builds, your body breaks down. That’s the amount of protein you’d get from six chicken breasts! When you’re sick or injured, you break down even more. As protein breaks down, amino acids are released.

In case it’s ever a Trivia question, or you want to sound extra smart with your friends, amino acids are compounds made of nitrogen, hydrogen, carbon, and oxygen.

Twenty-two amino acids combine in different patterns throughout your body to form the proteins that create each of the tissues that make you, you.

As the 250 to 300 grams of protein break down each day, some of the amino acids are reused. Kind of like how you can recycle cardboard and make printer paper.

Other amino acids are released into the blood to maintain its normal “pool” of amino acids for normal metabolic functions. Your heart and skeletal muscle use certain amino acids for energy production.

And still, other amino acids are lost. Your body can’t store extra protein like it can store fat or carbohydrates, so you have to consistently eat enough to support your daily needs.

Read more: “High-Protein Diets: Health Benefits and Controversies

Types of Amino Acids

Amino acids are either proteinogenic (protein-forming), or non-proteinogenic (non-protein-forming). The only reason I mention the two categories is that there are a number of non-proteinogenic amino acids that provide health and performance benefits that I won’t cover in this article, including amino acids like carnitine, ornithine, citrulline, glycine, and beta-alanine.

In this article, I focus on the proteinogenic amino acids, as they are the most important for maintaining optimal health and peak performance.

Proteinogenic amino acids fall into three different categories:

  1. Non-essential amino acids
  2. Conditionally essential amino acids
  3. Essential amino acids

Non-essential amino acids are important for your health, but they’re called non-essential because you produce them on your own.

Conditionally essential amino acids can usually be produced by your body. However, under certain circumstances, your body’s production can’t keep up with its demand, so you must get them through your diet or supplements.

Glutamine is a conditionally essential amino acid. Under high levels of stress, injury, or when someone is severely burned, glutamine stores drop considerably, and you’d need to eat or supplement glutamine to keep up with your body’s needs. Glutamine is often recommended to support gut health, especially in those who may experience a leaky gut.

Essential amino acids are “essential” because they cannot be made by the body. You must get them through diet or supplementation.

Of the essential amino acids, three are superstars. These are the branched-chain amino acids (BCAAs): leucine, isoleucine, and valine. BCAAs make up about 35 percent of your muscle tissue.

Non-Essential Amino Acids Essential Amino Acids
Alanine Histidine
Arginine Isoleucine**
Aspartic Acid Leucine**
Cysteine* Lysine
Glutamic Acid Methionine
Glutamine* Phenylalanine
Glycine* Threonine
Proline* Tryptophan
Serine* Valine**
*Conditionally Essential Amino Acid **Branched-Chain Amino Acid

Protein Synthesis and Breakdown

Your ability to maintain, or build lean body mass or muscle, is based on the levels of protein synthesis and protein breakdown throughout the day. As you age, protein breakdown tends to accelerate. Of course, there is much you can do to slow the protein breakdown, including eating more protein and/or supplementing with amino acids.

Lean Body Mass = Protein Synthesis – Protein Breakdown

When protein breakdown exceeds protein synthesis, your body is in a “catabolic” state. Think of someone with anorexia, cancer, or sarcopenia. They quickly lose muscle tissue because breakdown is greater than protein synthesis.

On the other hand, think of an 18-year-old boy going through the later stages of puberty. He goes from being lanky and awkward to developing biceps and shoulders. In this case, protein synthesis exceeds protein breakdown.

Every tissue in your body breaks down, wears out, and needs to be replaced from time to time. As a matter of fact, tissues that form your heart break down and get replaced every 30 days. In essence you get a brand new heart every month!

Another example is exercise; especially strength training. Weight training causes microscopic damage to your muscle tissue. That’s a good thing, because after your body repairs its muscles, they grow back stronger than they were before.

Hormones, stress, a lack of sleep, disease, nutrient deficiencies, inflammation, and other factors also influence your rates of protein synthesis and breakdown, but not as significantly or as quickly as exercise and amino acid intake. With good nutrition and exercise choices, you can do much to support lean body mass.

That brings us to your diet. How do you support your body’s protein needs? By eating more protein and/or amino acids.

From a Piece of Meat to an Amino Acid

Protein from your T-bone steak, post-workout shake, or chicken salad all look the same after your stomach does its job. The hydrochloric acid in your stomach, combined with the digestive enzymes secreted by your pancreas, help break down protein to teeny-tiny amino acids.

Once the amino acids are released from your steak, they easily pass from your digestive system into the blood stream, where blood vessels carry the amino acids to tissues that need them.

When they reach their destination, most are put together in unique combinations to form proteins, which create the various tissues throughout your body.

It sounds pretty simple, unless someone’s digestive system isn’t working well. To effectively break down protein to amino acids, you need to produce sufficient hydrochloric acid (HCl) and digestive enzymes.

Stress, aging, exercise, and medications reduce your production of HCl. Those same factors, along with certain diseases, reduce your production of enzymes. Without HCl and enzymes, you won’t break the protein down to amino acids properly.

This isn’t the topic of this article, but for those who do have difficulty producing enough stomach acid or digestive enzymes, both can be supplemented.

When people struggle to break down protein properly, amino acid supplements can come in handy. Amino acids don’t have to be broken down. They already are. So they’re easily absorbed after they’re consumed.

Remember the equation from above?

Lean Body Mass = Protein Synthesis – Protein Breakdown

To maximally stimulate protein synthesis, you only need 8 to 10 grams of essential amino acids in a meal or snack. You can take the 8 to 10 grams of amino acids as a supplement, or you could get 8 to 10 grams of essential amino acids by consuming about 20 grams of whey protein, or 25 to 30 grams of other animal-based protein sources.

That doesn’t mean you only need 25 to 30 grams of protein, though. While 8 to 10 grams of essential amino acids maximally stimulates protein synthesis (one part of the equation), you can continue slowing protein breakdown by eating more protein.

In fact, research has shown that eating 75 grams of protein in a single sitting slowed protein breakdown more than meals with lesser protein. That’s a lot of protein, and you’ll probably be full before you eat that much. I only bring this up because there is a myth about protein, that you only benefit from 30 grams, and no more. That’s nonsense.

Maximizing Amino Acid Intake

Animal proteins are rich in essential amino acids. Whey protein is considered the best protein because it’s so rich in essential amino acids. If you tolerate whey, use it! If not, you’ll need to pick a different protein source.

Soy protein is also rich in essential amino acids, but soy is surrounded by controversy (especially genetically-modified soy), so you might be better off avoiding it.

If you’re dead set on avoiding animal protein, you’ll need to use a plant-based protein supplement like pea, rice, and/or hemp protein. It’s very difficult to consume enough amino acids through plant-based foods alone.

Of course, you can easily increase your amino acid intake by using an essential amino acid supplement, too!

Essential Amino Acids and Aging

The same amount of protein has less of an effect on stimulating protein synthesis for older adults than it does for younger adults. Older adults have to eat more protein to get the same effects as when they were younger. This is called anabolic resistance.

The trouble is, older adults also have less of an appetite, and often, they produce less hydrochloric acid and digestive enzymes.

So, even when they eat more protein, they may have difficulty breaking it down, unless they supplement with enzymes and HCl.

Supplementing with branched-chain amino acids stimulates protein synthesis and decreases protein breakdown. The amino acids are readily absorbed, as they require no digestion, making them very convenient for older adults with less of an appetite and a less effective digestive system.

Loss of lean mass, beginning with middle age, is common, but it doesn’t have to happen at the rate it does for most people. Strength training, plus a higher-protein diet and/or amino acid supplementation can slow the rate of muscle loss.

Aging also causes a change in muscle fiber type, from fast-twitch to slow-twitch fibers. The fast-twitch fibers help maintain normal blood sugar. Amino acid supplementation has been shown to help maintain more fast-twitch, type II muscle fibers.

In the following sections, I’ll outline some of the most significant amino acid benefits.

Essential Amino Acids and Muscle

Though amino acids help build muscle, they can also be used by muscle tissue as fuel. As a result, they can help improve physical or exercise performance in athletes, and even in older adults.

Essential amino acid supplementation has been shown to improve the distance older adults could walk before fatigue, or younger athletes could train before wearing out. Branched-chain amino acids may reduce delayed onset muscle soreness (DOMS) following exercise.

Not only does skeletal muscle use amino acids for energy, but the heart can too.

Branched-chain amino acid supplementation has been shown to stimulate mitochondrial biogenesis, the creation of new mitochondria. Mitochondria are the powerhouses of the cells.

Most mitochondria are found in muscle cells, especially type I, slow-twitch muscle fibers. As people age or lose muscle, they also see a loss of mitochondria. BCAAs may slow the loss.

Essential Amino Acids and Post-Injury or Bedrest

After an injury, your body needs the right nutrients and amino acids to repair the damaged tissues. However, it’s also important that you maintain muscle throughout the rest of your body while your activity and exercise are limited.

In fact, the combination of exercise with any muscle groups that can still be used, plus a higher intake of amino acids, can stimulate the right hormones and provide the right nutrients to speed up the recovery process.

For example, following my Achilles tendon reattachment surgery on my left leg, I could still train my right leg and my upper body. Following my bicep tendon rupture and reattachment on my left arm, I could still train the right side of my upper body and my legs.

This created a better hormonal environment to speed up the recovery process. Meanwhile, I also took a higher-than-normal amount of essential amino acids to support the rebuilding of healthy tissues, while at the same time helping to maintain muscle throughout the rest of my body.

Branched-chain amino acid supplementation has also been shown to support normal inflammatory levels, which is important for optimal health and healing.

Essential Amino Acids and Weight Management

When you reduce carbs, calories, and your overall food intake to reduce weight, you tell your body, “You’re going to get fewer calories, so you need to get rid of some weight.”

Your body is very smart. It knows that muscle burns more calories than fat. So, if you don’t give your body a reason to keep its muscle, it’ll shed muscle as quickly as it sheds fat.

I can often tell when someone’s followed a low-calorie, lower-protein diet without any strength training. They become “skinny fat:” Their body-fat levels are still quite high, they just look skinnier — but not leaner. They might fit in smaller pants, but they’re not necessarily any healthier.

To maintain muscle, and shed body fat, you must combine strength training with a higher-intake of protein and/or essential amino acids.

Even though your total calorie intake might decrease, protein and amino acid needs increase while on a weight-reduction program.

Personally, I believe that using an essential amino acid supplement in place of a couple snacks each day is a powerful way to support your metabolism and maintain muscle, while minimizing your total calorie and carbohydrate intake.

Essential amino acids also help maintain normal blood sugar levels, which then helps maintain lower insulin levels. When insulin levels are low, your body can burn more fat for fuel, another important component to reducing body fat.

Supplementing with BCAAs has been shown to stimulate the hormone leptin, which decreases hunger. BCAAs have also been shown improve blood-sugar regulation.

You might also find that supplementing with essential amino acids gives you more energy while dieting. Since they can be used for energy production by the heart and muscles, some people notice an improvement in energy levels, especially if they’re not consuming enough high-quality protein.

Essential Amino Acids and Mood/Emotions

Some amino acids are precursors to serotonin, dopamine, and norepinephrine. Supplementing with branched-chain amino acids has been show to help improve mood and lessen feelings of stress.

In addition, BCAAs have also been shown to support normal brain and cognitive function. They’ve even been studied for their effects on supporting normal recovery from traumatic brain injuries.

In my opinion, men and women often skip meals, or eat meals with subpar levels of essential amino acids, leaving their bodies feeling depleted. While amino acids may not increase energy the way a cup of coffee or green tea will, I do believe they can help you maintain a baseline feeling of energy if you’re not getting proper nutrition.

Amino Acid Frequently Asked Questions

Do I need to supplement with amino acids, or can I just eat more protein?

I would always recommend eating enough protein over anything else. For optimal health, I believe one gram of protein per pound body weight (or your goal body weight if you’re on a weight-loss diet) is ideal.

Supplementing with essential amino acids can help close a nutrition gap if you’re inconsistent with your protein intake. Even when you do eat enough protein, you can still get an ergogenic effect from supplementing with BCAAs when they are timed appropriately.

Should kids or young adults use amino acids?

Young adults are very sensitive to good nutrition (especially a high-protein diet) and regular strength training. While amino acid supplementation is totally safe, and might provide a small benefit, they may not experience the same results as an older adult might.

When is the best time to supplement with amino acids?

The two best times for most people to supplement with essential amino acids are between meals and following a workout.

For older adults, supplementing between meals may be especially beneficial to combat the higher rates of protein breakdown common with aging.

For athletes, supplementing with EAAs before and during exercise improves performance. However, I believe there is an advantage to not using them before and during regular workouts or training and instead reserving them for use before and during competition or sport.

By training without amino acids (or other nutrients or antioxidants before or during training), you create a greater cortisol and growth hormone response, and produce more free radicals.

Although you want to avoid CHRONIC high cortisol and free radical production, short-term exposure is actually good for you. Your body is designed to handle stress and free radical production, and gets better at it if you expose it to physical stress periodically. Consuming antioxidants and nutrients before and during training blunts this effect.

Who should use an amino acid supplement?

I believe the people who benefit the most are:

  • Middle-aged and older adults, regardless of whether they exercise or not
  • Athletes and weekend warriors, following training sessions, and before, during, and after competition or games.
  • Anyone following an injury or illness to support normal inflammatory levels, tissue repair, and immune function
  • Anyone who won’t have time for a high-protein meal on occasion

What should I look for in an essential amino acid supplement?

First, look for the branched-chain amino acids (leucine, isoleucine, and valine) in a 2:1:1 ratio. This ratio has the most scientific support for the benefit of BCAAs.

Next, look for a low/no sugar, naturally-sweetened product. Plain amino acids taste nasty, which is why most companies use artificial sweeteners to mask the taste. Naturally sweetening them costs a lot more, so most companies don’t do that. Better to avoid the artificial sweeteners and find a brand that doesn’t contain them.

Third, look for a product that contains additional, ergogenic amino acids, such as ß-alanine, citrulline, arginine, and glutamine. These may also enhance performance and recovery, as well as further stimulate protein synthesis or decrease protein breakdown.

Amino Acids: Summing it Up

Whew! That was a lot of info, wasn’t it?

If you skipped right to the summary, I’d really recommend reading the whole article. After you do, you’ll see your food choices from a whole new perspective. The largest part of the population is the Baby Boomer generation, and in my opinion, that’s who needs to consider their protein and amino acids intake the most.

To sum things up:

  • Most people don’t eat enough protein or amino acids on a daily basis to support optimal health.
  • Essential amino acids must come from your diet, and animal-based proteins are the richest sources.
  • Branched-chain amino acids stimulate protein synthesis, decrease protein breakdown, and may slow the loss of muscle common when dieting, aging, or under chronic stress.
  • Branched-chain amino acids support the building of healthy tissues, may enhance one’s mood, and have been shown to support optimal cognitive function.


Keep the conversation going.

Leave a comment, ask a question, or see what others are talking about in the Life Time Health Facebook group.

The Life Time Health Team

Thoughts to share?

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