D-Amino Acid: Benefits & Dosage

06/18/2021 | 5 min. read

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D amino acids are basically amino acids with a D-configuration — they are primarily concerned with bacterial cell walls and non-human biology, though they do make the occasional appearance in things such as in human saliva — including free D-amino acids D-​alanine and D-proline — or as markers for disease since they are typically not inherently produced within the human body.

But, as the general public dives deeper into nutrition, including what amino acids should be included in the supplements they take, D amino acids have become a hot topic.

At its most basic, when it comes to nutrition and supplements, you should be focusing on the nine essential amino acids when it comes to supporting your health, unless you’re a bacterium.

Here’s what you need to know about the amino acids actually essential to you, and some just-for-fun info about D amino acids for the scientists in the audience!

A Primer on Amino Acids

Amino acids are organic compounds, made of nitrogen, carbon, hydrogen, and oxygen. They’re vital for functions such as protein synthesis, tissue repair and nutrient absorption. These vital compounds are found in plant-based food that helps you maintain a balanced, heart-healthy diet. You will also notice an improved mood, sleep, and energy level.

Many great sources of amino acids come through foods, which is why diet is so important. The way it works is this: when you eat protein, it’s broken down into amino acids that are used afterward to help your body build muscle, support your immune system function, and more.

The nine essential amino acids are made up of:

  • Phenylalanine is a precursor for tyrosine, dopamine, epinephrine, and norepinephrine. This plays a big role in the structure of forming proteins and enzymes, while furthering the production of other amino acids.
  • Valine helps with muscle growth, and helps create energy. Valine is a three-branched chain amino acid, so it can branch off to one side of its molecular structure.
  • Thronine deals with collagen and elastin, and is integral with skin and connective tissue.
  • Tryptophan may cause drowsiness, but is also a precursor to serotonin, which helps regulate your appetite, sleep and mood.
  • Methionine is used with your metabolism, detoxification, and tissue absorption.
  • Leucine helps regulate blood sugar, heals wounds, and produces growth hormones, and encourages muscle repair.
  • Isoleucine is heavily concentrated in muscle tissue, but also important to energy buildup and immune system function.
  • Lysine is incredibly key in protein synthesis, hormone production, enzyme production, and calcium absorption.
  • Histidine produces histamine, which is a neurotransmitter vital to immune response, digestion, sexual function and sleep cycles.

Amino acids are essential in many of your systems most important processes. They are often recognized for their role in muscle growth and repair, but as you’ve seen above, they are responsible for many other functions, including nervous system function, reproductive organs, immune system function, and digestive systems.

The branched-chain amino acids (BCAAs) make up a large portion of the body’s acid pool, or about 40% of all essential amino acids. BCAAs are broken down in the muscle, mainly, rather than the liver like some often think. BCAAs are involved in several of your body's functions, such as regulating blood sugar, and building protein and muscle.

In addition to the way BCAAs affect your body's functions, they also reduce fatigue and help create energy, and reduce serotonin production. Of all three BCAAs, leucine carries the biggest impact on your body’s ability to build up muscle proteins.

If you aren’t receiving enough amino acids through your diet, you may want to consider amino acid supplements.

The dosages of these nine essential amino acids recommended are:

  • Histidine - 14 mg
  • Isoleucine - 19 mg
  • Leucine - 42 mg
  • Lysine - 38 mg
  • Methionine (+ the non-essential amino acid cysteine): 19 mg
  • Phenylalanine (+ the non-essential amino acid tyrosine): 33 mg
  • Threonine - 20 mg
  • Tryptophan - 5 mg
  • Valine - 24 mg

Food is the most important way to get protein. A few foods, such as soy, quinoa, and buckwheat are all plant based examples of foods that contain all nine amino acids.

Some foods that are important in getting the amino acids you need include:

  • Meat
  • Seafood
  • Poultry
  • Eggs
  • Dairy

What Amino Acids Do In Your Body

Amino acids have countless benefits to your health, and aid in many of your body’s most important processes.

Mood and Sleep

The amino acid tryptophan is necessary in the production of serotonin, which is the hormone that regulates your mood, sleep, digestion, and more. Low serotonin levels result in depression, difficulty sleeping, and low energy. Supplementing tryptophan can reduce these symptoms and help improve sleep.

Helps With Exercise Performance

Three branched-chain essential amino acids - valine, leucine, and isoleucine - are used to soften the effects of fatigue, and tiredness, while also improving exercise energy, ability, and muscle recovery.

Muscle Loss Prevention

Muscle loss can occur as a side effect of illness, sickness, and bed rest. Amino acids preserve your body mass, improve muscle function and prevent muscle breakdown.

Promotes Weight Loss

Amino acids may also be responsible for triggering fat loss. Amino acids are making all the body's functions enhanced, and by helping your immune system and digestive system function better, desired weight loss may result as a positive side effect.

The Science Behind D Amino Acids

The Differences Between L and D Amino Acids

D-Amino acids are amino acids where the stereogenic carbon alpha to the amino group has a D-configuration. All other naturally occurring amino acids are configured in an L-configuration, known as L amino acids. Both types of amino acids are enantiomers. D-amino acids are the enantiomeric counterparts of L-amino acids.

L-amino acids are essential for life, and are the type of amino acids that get referenced the most as they provide the foundation for proteins across all mammals, including humans. D-amino acids, including d-alanine, and d-glutamic acid, are key constituents of peptidoglycan and are essential in microbial physiology — specifically, as a component of the bacteria’s cell wall.


Amino acids can be a little confusing to understand, but the main things to remember are that your body can’t produce essential amino acids, so they need to be supplemented to you through your diet or capsules.

There are many foods that support a heart healthy diet that make it easy to incorporate amino acids into your diet, but you can easily obtain amino acids through amino acid specific supplements or multivitamins.

As for D amino acids — the most you need to know is that they don’t really provide nutritional support for humans, and you should shift your focus to the nine essential amino acids your body actually needs.

Healthy Directions Staff Editor