Amino acids are the building blocks of all proteins in the body. But they do not all have the same nutritional status, and that difference is relevant to any formulator or brand working with such ingredients.
Understanding the distinction between essential and non-essential amino acids allows better decisions to be made about what to include in a formula, in what dosage and for what purpose.
What are amino acids?
Amino acids are organic molecules that the body uses to synthesise proteins, enzymes, neurotransmitters, hormones and other biologically active compounds. In total, the human body needs 20 amino acids to function properly.
Essential Amino Acids: What are they and what are they?
Essential substances are those that cannot be synthesised by the body itself (or not in sufficient quantity) and must therefore be obtained through diet or supplementation.
The nine essential amino acids are:
- Histidine
- Isoleucine
- Leucine
- Lysine
- Methionine
- Phenylalanine
- Threonine
- Tryptophan
- Valina
The last three in the list - leucine, isoleucine and valine - are also known as BCAAs (branched-chain amino acids) and are particularly relevant in sports nutrition because of their role in muscle synthesis and recovery.
Non-essential amino acids: what are they and why do they still matter?
Non-essential amino acids are those that the body itself can synthesise from other compounds. However, under certain circumstances (intense stress, illness, high-intensity exercise, ageing), the demand may exceed the capacity for endogenous synthesis. This is why we also speak of conditionally essential amino acids.
Relevant examples in formulation:
- Glutaminethe most abundant amino acid in muscle; important for recovery and gut health.
- Argininenitric oxide precursor, linked to cardiovascular and sports performance.
- Glycineinvolved in collagen synthesis and nervous system function.
- TaurineFrequent in energy and cognitive performance formulas.
Applications in nutraceutical supplementation
Depending on the purpose of the formula, amino acids are used in different combinations:
- Sports performanceBCAAs, glutamine, creatine, beta-alanine.
- Muscle recoveryLeucine, HMB (leucine metabolite), glutamine.
- Cognitive healthTryptophan (serotonin precursor), tyrosine (dopamine precursor).
- Sleep and relaxation: tryptophan, glycine, theanine.
- Joint and connective tissue healthGlycine, proline, lysine (collagen coenzymes).
Considerations for the formulator
The chemical form of the amino acid (free, chelated, dipeptide) directly affects its bioavailability and ease of integration into the formula. Free forms have a higher absorption rate, while peptides have advantages in stability and palatability.
Purity and traceability of origin are also crucial criteria: it is important to verify whether the amino acid comes from plant (fermentation) or animal sources, especially when the target market includes vegan or religiously restricted consumers.
In a nutshell
The distinction between essential and non-essential does not imply that one is more important than the other: both groups are necessary for the proper functioning of the body. In nutraceutical formulation, the key is to select the right amino acids for the right purpose, in the right chemical form and with guaranteed quality.
At Sanmart we have a wide range of ingredients in this category, with GMP and ISO certifications and full traceability. Consult our catalogue or contact our technical team for more information.
Spanish 
English 
French