Source Naturals L-Proline 275 / L-Lysine 275 (120 Tablets): Targeted Amino Acid Support for Collagen Synthesis & Arterial Integrity
Collagen serves as the internal "scaffolding" of the human body. It holds skin firm, cushions joints, and reinforces the elastic walls of blood vessels. However, swallowing generic collagen peptides does not always guarantee your body has the exact amino acid building blocks required to assemble healthy tissue where it is needed most. Source Naturals L-Proline 275 / L-Lysine 275 delivers pure, free-form amino acids paired with key co-factors to fuel your body’s natural collagen factory from the inside out.
Product Snapshot
✓ Balanced Dosing: 275 mg of pure L-Proline and 275 mg of L-Lysine per tablet (1.1 g each per 4-tablet serving).
✓ Essential Co-Factor: 1,000 mg of buffered Vitamin C to activate collagen-synthesizing enzymes.
✓ Purity Standard: Vegetarian formula free from gluten, soy, dairy, yeast, and synthetic preservatives.
The Science of Collagen: How L-Proline and L-Lysine Rebuild Connective Tissue
To understand why this specific formula is so effective, think of collagen like a strong, three-ply rope (the "triple helix"). Your cells cannot weave this triple-stranded rope without two critical raw ingredients: L-Proline and L-Lysine.
1. L-Proline: The Structural Core
L-Proline is an amino acid that provides the tight, interlocking shape needed to form a stable collagen helix. Inside the body, it is modified into hydroxyproline. Hydroxyproline acts like molecular rivets, locking the strands in place so your skin maintains bounce, cartilage resists wear, and tendons withstand physical strain (Shoulders & Raines, 2009).
2. L-Lysine: The Essential Cross-Linker
L-Lysine is an essential amino acid, meaning your body cannot manufacture it—it must come from your diet or targeted supplementation. In collagen assembly, lysine transforms into hydroxylysine, which builds tough cross-links that bind individual collagen ropes together into resilient tissue mats. Lysine is also the primary biochemical precursor for carnitine, a nutrient needed to convert fats into cellular energy (Flanagan et al., 2010).
3. Vitamin C: The Enzymatic Catalyst
Proline and lysine cannot transform into their active collagen-building forms without an enzyme catalyst. That catalyst depends directly on Vitamin C (ascorbate). Specifically, enzymes called prolyl hydroxylase and lysyl hydroxylase require vitamin C to lock proline and lysine into position (Kivirikko & Myllyharju, 1998). Source Naturals includes a robust 1,000 mg dose of buffered Vitamin C (as calcium ascorbate and ascorbic acid) so this enzymatic pathway operates at maximum efficiency without upsetting sensitive stomachs.
Cardiovascular Support & Arterial Integrity: The Pauling-Rath Protocol Connection
While most people recognize collagen for smoothing wrinkles or easing joint stiffness, its most critical job is maintaining elastic blood vessels. The endothelial lining and medial wall of your arterial system rely heavily on high-tensile collagen fibers to stretch with every heartbeat and withstand normal blood pressure.
In the early 1990s, two-time Nobel Laureate Dr. Linus Pauling and Dr. Matthias Rath published a well-known nutritional hypothesis regarding arterial wellness. They observed that when arterial walls become stressed or depleted of collagen, the body attempts to "patch" those weak points by depositing sticky lipid particles known as Lipoprotein(a), or Lp(a) (Rath & Pauling, 1991).
How Free-Form Lysine & Proline Protect Arteries:
✓ Receptor Binding: Free-form L-Lysine and L-Proline compete for the binding sites that anchor Lp(a) and oxidized lipoproteins to blood vessel walls.
✓ Vascular Wall Renewal: Supplying continuous amino acid building blocks helps the vascular matrix maintain natural elasticity and repair tiny micro-abrasions caused by circulatory stress.
✓ Nitric Oxide Balance: Healthy connective tissue around blood vessels allows vascular smooth muscle to dilate and contract freely.
*Medical Notice: While the Pauling-Rath protocol has been studied and used by integrative cardiologists for decades, dietary supplements do not replace prescribed cardiovascular therapies, statins, or blood pressure medications. Always share your complete supplement routine with your healthcare provider.
The Botanical Shield: Hawthorn Berry & Grape Seed Extract
Synthesizing brand-new collagen is only half the battle. Your body must also defend that new tissue against matrix metalloproteinases (MMPs)—enzymes driven by oxidative stress and inflammation that break collagen fibers down prematurely. To prevent this, Source Naturals reinforces this formula with two botanicals:
Hawthorn Berry Extract (100 mg)
Hawthorn (Crataegus oxyacantha) has a centuries-long history in cardiovascular herbalism. Modern clinical trials show that hawthorn bioflavonoids improve coronary blood flow, support healthy cardiac muscle contraction, and protect delicate micro-capillaries from oxidative strain (Pittler et al., 2008).
Grape seed extract is one of nature’s most concentrated sources of oligomeric proanthocyanidins (OPCs). Research demonstrates that OPCs have a natural chemical affinity for collagen and elastin fibers, physically binding to them to shield structural proteins from free radical oxidation and enzymatic degradation (Bagchi et al., 2000).
Every batch of Source Naturals L-Proline / L-Lysine is manufactured under strict cGMP guidelines. The exact ingredient profiles per full serving (4 tablets) and individual tablet (275 mg each) are outlined below:
Active Ingredient
Amount Per Serving (4 Tablets)
Amount Per 1 Tablet
% Daily Value (%DV)
Vitamin C (as calcium ascorbate & ascorbic acid)
1,000 mg
250 mg
1,111%
Calcium (as calcium ascorbate)
66 mg
16.5 mg
5%
Magnesium (as magnesium citrate)
46 mg
11.5 mg
11%
L-Lysine (as L-lysine hydrochloride)
1.1 g (1,100 mg)
275 mg
† Daily Value Not Established
L-Proline
1.1 g (1,100 mg)
275 mg
† Daily Value Not Established
Hawthorn Berry Extract
100 mg
25 mg
† Daily Value Not Established
Grape Seed Extract (Proanthodyn™ 95% value)
100 mg
25 mg
† Daily Value Not Established
Product Specifications:
Other Ingredients: Microcrystalline cellulose, sorbitol, stearic acid, silica, and magnesium stearate.
Allergen Declaration: Suitable for vegetarians. Contains NO yeast, dairy, egg, gluten, soy, or wheat. Formulated without sugar, salt, artificial colorings, artificial flavors, or chemical fragrances.
Packaging Details: 120 Tablets per bottle (30 full 4-tablet servings, or 60 two-tablet servings). SKU: SN0758 | UPC: 021078007586.
How to Use: Dosage Instructions & Clinical Safety
Suggested Daily Usage
Take 2 to 4 tablets daily with meals, or as directed by your healthcare professional. For maximum absorption, take your dose with breakfast or lunch alongside plenty of water. Splitting your intake into two tablets twice daily maintains consistent blood levels of free-form amino acids throughout the day.
Safety Guidelines & Contraindications
Pregnancy & Nursing: If you are pregnant, planning to become pregnant, or breastfeeding, consult your OB/GYN before starting this product.
Cardiovascular Medications: Hawthorn extract may interact with prescription cardiac medications, including digoxin, beta-blockers, and calcium channel blockers. Always check with your cardiologist.
Renal (Kidney) Concerns: Individuals with pre-existing renal disease or impaired protein excretion should monitor amino acid supplementation under nephrology supervision.
Herpes Simplex Balance: L-Lysine is widely used to suppress viral replication by competing with L-Arginine. This formula is safe for individuals prone to cold sores.
Frequently Asked Questions (FAQ)
Why is the product named "L-Proline 275 / L-Lysine 275" if the bottle says 1.1 grams?
The name "L-Proline 275 / L-Lysine 275" indicates the precise quantity of each amino acid inside one individual tablet (275 mg of L-Proline and 275 mg of L-Lysine). The standard daily serving size listed on the manufacturer's Supplement Facts panel is 4 tablets, which delivers 1.1 grams (1,100 mg) of L-Proline and 1.1 grams of L-Lysine.
Why take free-form L-Proline and L-Lysine instead of collagen peptide powder?
Collagen powders must first be broken down by stomach acid and digestive proteases into smaller di- and tri-peptides. Free-form amino acids require minimal digestive breakdown and enter systemic circulation quickly. Furthermore, this formula guarantees high, targeted ratios of proline and lysine paired with therapeutic doses of buffered Vitamin C, which collagen powders usually lack.
How does Vitamin C improve the performance of this supplement?
Vitamin C acts as an essential electron donor for two enzymes: prolyl hydroxylase and lysyl hydroxylase. Without adequate Vitamin C, your body cannot convert proline into hydroxyproline or lysine into hydroxylysine. By providing 1,000 mg of Vitamin C per serving, Source Naturals ensures your biological collagen machinery works without metabolic bottlenecks.
Is this formula suitable for vegetarians and vegans?
Yes. Traditional collagen supplements are sourced from bovine hides, chicken cartilage, or fish scales. The L-Proline and L-Lysine in this formula are produced via microbial fermentation, making it 100% vegetarian and free from animal-derived collagen tissues.
Can I take this supplement if I am taking blood pressure medications?
Because this formula includes 100 mg of Hawthorn berry extract, which promotes healthy microcirculation and blood vessel dilation, anyone taking blood pressure prescriptions, beta-blockers, or cardiac drugs should consult their prescribing physician before use.
How long does it take to notice results for skin and joints?
Connective tissue turnover takes time. While free-form amino acids begin absorbing within hours of ingestion, structural matrix renewal in the skin typically becomes visible after 4 to 8 weeks of consistent use. Tendons, ligaments, and arterial lining rebuild on a 3- to 6-month cycle.
Scientific References & Authoritative Citations
Shoulders, M. D., & Raines, R. T. (2009). Collagen structure and stability. Annual Review of Biochemistry, 78, 929-958. DOI: 10.1146/annurev.biochem.77.032207.120833.
Flanagan, J. L., et al. (2010). Role of carnitine in disease. Nutrition & Metabolism, 7(1), 30. DOI: 10.1186/1743-7075-7-30.
Kivirikko, K. I., & Myllyharju, J. (1998). Prolyl 4-hydroxylases, the key enzymes of collagen biosynthesis. Matrix Biology, 16(7), 357-368. PMID: 9501378.
Rath, M., & Pauling, L. (1991). Solution to the puzzle of human cardiovascular disease: Its primary cause is ascorbate deficiency, leading to the deposition of lipoprotein(a) and fibrinogen in the vascular wall. Journal of Orthomolecular Medicine, 6(3-4), 125-134.
Pittler, M. H., Guo, R., & Ernst, E. (2008). Hawthorn extract for treating chronic heart failure. Cochrane Database of Systematic Reviews, (1), CD005312. DOI: 10.1002/14651858.CD005312.pub2.
Bagchi, D., et al. (2000). Free radicals and grape seed proanthocyanidin extract: importance in human health and disease prevention. Toxicology, 148(2-3), 187-197. PMID: 10962134.
