Everything You've Ever Wanted to Know About Amino Acids | The Science, Pseudoscience, Gimmicks, and Gold

Everything You've Ever Wanted to Know About Amino Acids

There are dozens of amino acid supplements available on the market today. On one end of the spectrum, you have branched-chain amino acids available as workout and recovery supplements. On the other end of the spectrum, you have supplements claiming that their amino acid products are able to do everything from darken your skin to increase your base testosterone levels. 

Of all the categories of supplements available to you, amino acids are some of the trickiest for discerning what's beneficial from marketing gimmicks wrapped up in pseudoscience. 

As with any supplement, the usual red flags apply. If it makes exorbitant promises, sounds too good to be true, uses meaningless buzz words like "detox," or doesn't have any formal research to back up the claims being made, it's probably best to steer clear. Outside of this ever-handy set of rules, let's take a look at what amino acids are, what they do, and what to look for.

What Are Amino Acids?

Amino acids are the building blocks of proteins, and they play vital roles in innumerable bodily functions. They’re essential for the building of proteins and the synthesis of hormones and neurotransmitters.  

Without amino acids, your body's core systems could not function. 

Given their importance, our bodies have adapted to produce most of the amino acids that we need. The amino acids we don't naturally produce on our own are easily attainable in the foods that we eat. 

The amino acids we produce on our own are referred to as "non-essential," and the ones we have to get via food consumption are referred to as "essential." 

Don't let this naming convention confuse you. All of the core amino acids are necessary for your bodily functions– the distinction of essential versus non-essential only refers to whether you can produce them on your own or need to consume foods containing them. 

Essential Amino Acids

The nine essential amino acids perform a number of important and varied jobs in your body:

  • Phenylalanine: Phenylalanine is used to make chemical messengers, such as the neurotransmitters tyrosine, dopamine, epinephrine, and norepinephrine. 
  • Valine: Valine is a branched-chain amino acid (BCAA). Valine plays an important role in muscle growth and regeneration, making it particularly significant for folks who are active. 
  • Threonine: Threonine is a principal part of structural proteins such as collagen and elastin, which are important components of the skin and connective tissue. It also plays a role in fat metabolism and immune function.
  • Tryptophan: Tryptophan is needed to maintain proper nitrogen balance and facilitate the production of serotonin, a neurotransmitter that regulates your appetite, sleep, and mood.
  • Methionine: Methionine plays an important role in metabolism and detoxification– the bodily process, not the marketing buzzword. It’s also necessary for tissue growth and the absorption of zinc and selenium, minerals that are vital to your health.
  • Leucine: Like valine, leucine is a branched-chain amino acid (BCAA) that is critical for protein synthesis and muscle repair. It also helps regulate blood sugar levels, stimulates wound healing, and produces growth hormones.
  • Isoleucine: The last of the three branched-chain amino acids (BCAA), isoleucine is involved in muscle metabolism and is heavily concentrated in muscle tissue. It’s also important for immune function, hemoglobin production, and energy regulation.
  • Lysine: Lysine plays a major role in protein synthesis, hormone and enzyme production, and the absorption of calcium.
  • Histidine: Histidine is used to produce histamine, a neurotransmitter that is vital to immune response (if you've ever taken an antihistamine, you're already somewhat aware of how histamines function in your body as an immune response), digestion, sexual function, and sleep-wake cycles. 

Non-Essential Amino Acids

As mentioned above, non-essential amino acids are the amino acids that your body can usually produce on its own. During times of stress or illness, your body may not be able to produce all of them in adequate quantity, making it particularly necessary to ensure you're always consuming enough protein. 

The non-essential amino acids are:

  • Alanine: Alanine is used to break down tryptophan and vitamin B-6. It is a source of energy for muscles and the central nervous system. It strengthens the immune system and helps the body use sugars.
  • Arginine: Arginine helps your body build and repair muscles, and it functions as a vasodilator, making it a common ingredient in pre-workout supplements. There is also some research to suggest that taking supplemental l-arginine can help with heart health and erectile dysfunction.
  • Asparagine: Asparagine plays a role in the metabolic control of cell functions in nerve and brain tissue, and functions as a carrier to help your body eliminate ammonium from your system.
  • Aspartic acid: Aspartic acid plays a role in protein synthesis and the production of antibodies as a part of your body's immune response to potential pathogens. 
  • Cysteine: Cysteine fuels protein synthesis, specifically the protein beta-keratine, which is the main protein in your hair, skin, and nails.
  • Glutamic acid: Glutamic acid is used to synthesize glutamate, which helps nerve cells in the brain send and receive information. As a result, this amino acid may play a role in memory and learning. 
  • Glutamine: Glutamine is important for organ function and health, and is believed to be particularly important for intestinal health. 
  • Glycine: Glycine plays an important role in the transmission of chemical signals in the brain. Some researchers think glycine may play a role in both Alzheimer's disease and cancer prevention.
  • Proline: Proline plays an important role in the body's production of collagen, making it an important amino acid for skin health and healing. 
  • Serine: Serine is needed for the metabolism of fats, fatty acids, and cell membranes; muscle growth; and a healthy immune system
  • Tyrosine: Tyrosine is another amino acid that plays a role in the synthesis of neurotransmitters, and research suggests that adequate tyrosine levels are associated with mental alertness. 

Do You Need Amino Acid Supplements?

Given all of the vital functions that amino acids play in your bodily health, you may be wondering if you need to be consuming amino acid supplements to ensure that you have all the adequate levels necessary. 

As with any supplement, however, you most likely already have appropriate levels of amino acids from your diet. Any food that's rich in protein– both animal and plant-based proteins– is going to be able to be broken down into amino acids.

If you do have a fully plant-based diet, however, it may be necessary to double-check that you're eating a variety of plant-based protein sources to get each amino acid. Tofu, seitan, legumes, broccoli, peas, hemp seeds, spirulina, and quinoa are all fairly rich in various amino acids, so if you're getting a bit of each, you're probably good to go.

People who eat animal-based products have a little bit easier time getting all of the necessary amino acids. Most egg, dairy, poultry, beef, pork, and fish products individually contain all essential amino acids in varying doses.

While your diet likely already covers your amino acid intake needs, there may still be some benefit in taking an amino acid supplement in addition to eating a well-rounded diet. Different amino acids are associated with assorted health outcomes from treating minor erectile dysfunction to improving heart health to improving memory to improving athletic performance and recovery.

What AMino Acid Supplements Should I Consider?

If you're considering an amino acid supplement, it's important to match the specific supplement you're taking to the outcomes you're seeking. 

There are a few general amino acid supplements on the market, as well as specific compounds. 

For amino acid compounds, it's particularly important to look for brands that can back up their claims with clinical research. These types of supplements are not regulated by the FDA, and it's not uncommon for supplement brands to pay independent accrediting bodies to slap an "organic" or "certified pure" label on their products to make them seem more impactful than they are. 

A company like Amino Co is a great example of an amino acids company that can back up their products with research. Amino Co actually started as a research company creating products for the likes of NASA, and they only recently moved into consumer products.  They publish their clinical trials, allowing you to see the observed efficacy of their products prior to purchase. 

Amino Co Heal, Life, and Perform are all supplements I take regularly because of their benefits and the research to back them up. 

Outside of amino acid compounds, individual amino acids can also be taken as a part of your dietary supplement regime. 

A lot of athletes, for example, take BCAAs. Branched-chain amino acids aid in muscle regeneration and sustaining energy during periods of muscle exertion. Most BCAAs that you can find at supplement shops, sporting goods stores, or pharmacies are going to be safe and fairly effective to take. I particularly prefer Optimum Nutrition, BSN, and Cellucor as brands to look for with BCAA supplements as they're fairly affordable, reliable, and have good brand reputations. 

Another popular amino acid supplement– and in my opinion, an underrated one– is glutamine. As mentioned above, glutamine helps with protein synthesis and muscle health, but it also benefits gut health. I, personally, most noted the benefits to gut health with improved regularity and less bloating after eating fibrous foods. The only downside to it is that the flavor is not great, so I wouldn't recommend drinking it on its own. Mixing it in with a flavored protein powder is how I took it. 

I liked the Bodybuilding.com Signature Series Micronized Glutamine because you could get a huge tub for a fairly low cost, however, it looks like they have since discontinued that product. In its place, I'd recommend Swolverine's L-Glutamine product since Swolverine has become my most recent go-to for nutritional products that are high-quality, transparent, and affordable.

Now You Know Aminos

Amino acids ensure your bodily health and functions. You probably already get adequate levels of each acid in your diet, but you can supplement your food intake with specific amino acid supplements to help along with specific processes. 

If you are sick or experiencing a period of significant stress, it's helpful to ensure that you're continuing to eat adequate amounts of protein as your body may not be able to produce amino acids in the way that it usually does. 

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