DL-185™ (Dileucine): What is it and how does it work?
DL-185™
DL-185™ (Dileucine): A New Direction in Muscle, Strength & Healthy Aging
Modern performance nutrition is moving beyond basic amino acids and into precision peptide delivery. One of the most discussed innovations in this space is DL-185™, also known as dileucine — a dipeptide form of leucine designed to improve absorption efficiency and biological impact.
Rather than adding more leucine, DL-185 focuses on how leucine enters the body and how effectively it contributes to muscle protein synthesis.
First, What Is a Peptide?
In nutrition, a peptide is simply a short chain of amino acids — the same basic building blocks that make up dietary protein. When protein from food is digested, it naturally passes through peptide forms before being absorbed and utilised by the body.
DL-185™ is a dipeptide, meaning it consists of two amino acid units bonded together — in this case, two molecules of leucine. It is consumed orally, handled through normal digestive processes, and broken down and utilised via established metabolic pathways.
From a nutritional perspective, DL-185 is not a drug, hormone, or injectable compound. It represents a structured form of a familiar dietary amino acid, designed to explore whether delivery format influences how leucine is absorbed and used.
Understanding this helps clarify that peptide-based ingredients in sports nutrition are an extension of normal protein biology, not something separate or foreign to the body.
What Is DL-185™ (Dileucine)?
DL-185™ is a dipeptide composed of two leucine molecules chemically bonded together. This structure allows it to behave differently from free leucine once ingested.
Instead of relying solely on standard amino acid transporters, dileucine can utilise peptide transport pathways, which are known to be faster and more efficient at moving nutrients from the gut into circulation.
In simple terms:
DL-185 is not “more leucine” — it is leucine delivered differently.
Why Delivery Matters
Leucine is well-known for its role in triggering muscle protein synthesis through the mTOR pathway. However, free leucine faces two key limitations:
Rapid oxidation before full utilisation
Diminished responsiveness in older or highly trained individuals
DL-185 was developed to address these issues by improving plasma leucine availability and prolonging its anabolic signalling window.
Human data shows that dileucine leads to:
Faster increases in circulating leucine levels
Greater stimulation of muscle protein synthesis compared to equivalent leucine doses
This suggests that delivery form plays a critical role in amino acid effectiveness.
DL185™ Muscle Protein Synthesis
What the Research Shows
In controlled human trials, DL-185 has demonstrated a greater increase in muscle protein synthesis compared to standard leucine when taken at equivalent amounts.
This is significant because muscle growth and recovery are driven not just by total protein intake, but by how strongly muscle protein synthesis is stimulated after ingestion.
Key observations from published research include:
Enhanced anabolic signalling compared to leucine alone
Improved efficiency per gram consumed
Stronger acute muscle protein synthesis response
These findings position DL-185 as a high-efficiency leucine delivery system rather than a simple amino acid replacement.
Importantly, the observed differences appear to relate to delivery format and utilisation, meaning the response seen with DL-185 cannot be assumed to be replicated by simply increasing the amount of free leucine consumed.
Strength & Performance Outcomes
Beyond laboratory measurements, DL-185 has also been evaluated in longer-term human training studies.
Over multi-week resistance training protocols, participants supplementing with dileucine experienced greater improvements in lower-body strength compared to control groups. Worth noting, this research was conducted in young adult men who were already resistance trained which is basically hard mode in a study context to get good results.
While the exact mechanisms are still being explored, improved amino acid availability and repeated stimulation of muscle protein synthesis are believed to contribute to these outcomes.
Importantly, these effects were observed without stimulant-like action or acute nervous system effects, reinforcing DL-185’s role as a structural nutrition ingredient rather than a stimulant.
Relevance for Aging & Muscle Preservation
As we age, the body becomes less responsive to amino acids — a phenomenon often referred to as anabolic resistance. This contributes to gradual muscle loss and reduced functional capacity over time.
DL-185 has drawn attention in this context because:
It improves amino acid delivery efficiency
It may help overcome reduced leucine sensitivity
It supports muscle protein turnover without excessive dosing
Maintaining muscle mass is increasingly recognised as a key factor in long-term metabolic health and physical independence, making peptide-based amino acid delivery a growing area of interest.
DL-185 vs Standard Leucine
Standard leucine is a well-established essential amino acid recognised for its role in stimulating muscle protein synthesis. When consumed as a free amino acid, leucine is absorbed through amino acid transporters and contributes effectively to anabolic signalling as part of normal dietary protein intake.
DL-185™, also known as dileucine, differs not in amino acid composition but in molecular structure. It is a dipeptide formed by bonding two leucine molecules together, allowing it to be absorbed via peptide transport pathways rather than standard amino acid transporters. Research has explored whether this difference in delivery influences how leucine is utilised in trained individuals.
How DL-185 Is Typically Used
In supplement formulations, DL-185 is commonly used in 2 gram-level daily doses, either:
As a standalone ingredient
Alongside creatine, peptides, or protein-support compounds
As part of performance or healthy-aging formulas
Because it does not rely on stimulatory pathways, it can be used daily, independent of training days.
Final Thoughts
DL-185 represents a shift in sports nutrition thinking — from simply increasing ingredient amounts to optimising biological delivery.
With human research supporting its role in:
Muscle protein synthesis efficiency
Strength development
Muscle preservation across age groups
Dileucine stands out as a next-generation amino acid peptide with applications that extend beyond traditional bodybuilding supplementation.
As peptide-based nutrition continues to evolve, DL-185 offers a glimpse into the future of performance and longevity-focused formulation.
Educational Disclaimer
Human studies discussed in this article were conducted in young, healthy adult populations. This content is provided for general educational purposes only and does not constitute medical or therapeutic advice.
*These statements have not been evaluated by the TGA. This product is not intended to diagnose, treat, cure or prevent any disease.
The information provided on this webpage is not intended to be medical advice or to replace professional medical advice, diagnosis or treatment.
This product should not be used to treat, cure or prevent any medical condition and is not to be used for therapeutic purposes.
We make no guarantee as to the results that you may experience from using this product or the information we make available on this webpage. Your results will depend on many factors, including but not limited to your age, gender, other products used, health history, exercise regimen, lifestyle and diet.
Please check with your health practitioner before making any changes to your diet or taking supplements, especially if you are pregnant, lactating or have a health condition. Always read directions for use carefully
