Best Seller L-Protein

SKU LD2004EU · Fasting Mimicking Diet

L-Protein

Formulated with 25g of complete, plant-based amino acids to support muscle synthesis and repair while also keeping IGF-1, a pathway known to accelerate aging, low for optimal aging. L-Protein is the only powder patent pending for healthy aging. Use it after a workout, as part of a healthy breakfast, or as a snack during your feeding window.

Optimal muscle and body support
High protein, low carbohydrates
Plant-based proteins
21 vitamins and minerals sourced from fruits and veggies
Clean ingredients: Plant-based & free from dairy, GMO, soy and silica
12 individual sachets per bag

Ships from Lonso Milan facility · 72h after order confirmation · free cold-chain shipping on orders over €1,500.

Longevity-aligned

Low methionine, sufficient leucine the macro profile linked to longer healthspan in Longo Lab research.

Lean-mass support

14 g of complete plant protein per sachet designed for patients at risk of sarcopenia after age 65.

Single-serve clarity

Pre-portioned bustine. No scoops, no guesswork useful for adherence in clinic-managed protocols.

How it fits the protocol

Between FMD cycles. In the over-65 cohort, daily.

Post-FMD recovery

One sachet on day 7 (post-refeed) supports lean- mass return. Particularly important for over-65 patients where rebound protein matters.

Sarcopenia at-risk

Daily sachet for patients aged 65+ or with documented appendicular lean-mass loss. Above- threshold leucine, low methionine — the safe- side macro.

Plant-protein gap

For vegan and Mediterranean-leaning patients whose total daily protein consistently lands under 1.0 g/kg. One sachet closes the gap.

What's in the sachet

14 g complete plant protein —engineered for the Longo macro rules.

Pea and brown rice are blended in a 65/35 ratio to close the amino-acid profile while keeping methionine intentionally low — the protein shape associated with longevity in both animal and human studies.

PER SACHET

9 g

Pea protein isolate

Pisum sativum · 85% protein

The dominant plant protein in the blend. Naturally high in arginine and lysine, low in methionine — the profile linked to lower IGF-1 in Longo Lab research. Complete digestibility (PDCAAS) when paired with brown rice.

Low methionine

PER SACHET

5 g

Brown rice protein

Oryza sativa concentrate

Pairs with pea protein to close the methionine + cysteine gap and complete the amino-acid profile (PDCAAS ≈ 1.0). The whole-grain origin also contributes B- vitamins and a mild caramel note to the chocolate sachet.

Complete blend

PER SACHET

2.5 g

Leucine threshold

2.5 g leucine / sachet

Above the 2.3 g leucine threshold needed to trigger muscle protein synthesis in older adults. Important for the sarcopenia-risk cohort — the single most under- served indication in the over-65 metabolic patient.

MPS-active

PER SACHET

—

Cocoa + mineral matrix

Cocoa, calcium, magnesium, iron

Natural cocoa for the chocolate flavour (no artificial sweeteners), plus a baseline mineral matrix that addresses the most common deficiencies seen in plant- protein diets — iron (4.2 mg) and B12.

No additives

Amino-acid profile · per 22 g sachet

Sufficient leucine.
Intentionally low methionine.

Whey hits leucine harder but at the cost of methionine — an amino acid that activates IGF-1 / mTOR pathways implicated in accelerated aging. L-Protein keeps leucine above the muscle protein synthesis threshold while staying low on methionine, on purpose.

Methionine

L-Protein 0.18 g · Whey 0.45 g · per 14 g protein

Leucine

L-Protein 2.5 g · Whey 2.4 g · both above MPS threshold

Arginine

L-Protein 1.4 g · Whey 0.4 g · plant-protein advantage

Biological Age Score · Nature Aging, 2024

Three cycles. 2.5 years younger, on the data.

In the Mishra et al. 2024 trial (n=144, RCT), patients completing three consecutive Prolon FMD cycles reduced their Levine PhenoAge by an average of 2.5 years versus controls.

Read the Trial →

3 yrs

Biological Age Δ

−1.30 pp

HBA1C (12 wk)

−7.4%

Trunk Fat

96%

1st-Cycle Completion

FAQs

How can L-Protein support longevity?

Many protein formulations on the market spike pro-aging pathways like IGF-1, and they’re packed with hidden sugars and other additives that can compromise your health. Based on our decades of research into nutrition, and studies on optimal IGF-1 levels, we developed our longevity proteins to support muscle—without triggering pro-aging pathways. We also made it with no shortcuts, no hidden ingredients, no tradeoffs. L-Protein is vegan, dairy-free, soy-free, silica-free (yes, many protein powders on the market are packed with silica as a filler), and free of artificial sweeteners. It’s the first protein truly designed to not only fuel your fitness today, but to help you thrive tomorrow.

How does L-Protein differ from other vegan protein powders?

Unlike other vegan protein powders, L-Protein uses peas, black beans and chickpeas as part of its overall protein composition rather than grain-based proteins like brown rice or oat powder, which helps to keep our composition lower in carbohydrates. The legumes we use are known to support healthy aging and are part of our overall healthy diet protocols, contributing a healthy dose of plant-based fibers to your diet. L-Protein includes extracts of whole vegetables like broccoli and mushrooms to enhance its nutrient composition and digestibility. Unlike other vegan brands, our protein powder is non-GMO, low carb, free of any harmful additives, gluten or soy. It’s made from whole ingredients, nothing else.

What is the difference between Prolon's Fasting Shake and L-Protein?

Our Fasting Shake is part of our intermittent fasting product line. It is intended to be consumed during your fasting window, as it will not break your fast or affect your ketone levels during time restricted feeding (TRF). Additionally, the Fasting Shake is also intentionally low in protein to stay below our body’s nutrient sensing pathways. L-Protein is consumed when you are eating food. It provides calories and a high dose of protein. It can be used as fuel post workout, as part of a healthy breakfast or lunch when you do break your fast, or it can simply be used as a supplement to increase your overall protein intake each day.

Can I have L-Protein when I am fasting?

No, L-Protein is not part of our intermittent fasting product line. It is intended to be consumed during your feeding window as part of your overall daily calories and protein goals.

How often can I use L-Protein?

L-Protein can be used daily to meet your overall daily protein goals. Be sure to consume this protein during your feeding window.

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