FUNDAMENTAL SERUM

Believe it or not, but for the last three years, while the R&D process was still ongoing, we were confident that the serum would be called Much More Than Moisturising Serum. How else could you name a product that has moisturization and hydration as its main functions, yet also works strongly as an anti-inflammatory? And, on top of that, restores homeostasis, soothes, detoxifies, firms, regenerates, improves blood circulation, brightens, and reduces under-eye dark circles?
Moisturising Serum would simply not be enough. Anti-inflammaging Serum would not be allowed - despite the fact that the active ingredients we use have proven and measurable efficacy in decreasing cortisol - because we are introducing the serum to the market as a cosmetic, not a drug. And according to cosmetics regulations, such claims cannot be made. What else could we call it? We’re great with formulations, but terrible with names - Much More Than Moisturising Serum was the best we could come up with. That was until we realized that everything this product covers are the essential and truly fundamental needs of skin. This is how the name Fundamental Serum came into the picture - and it immediately felt perfectly right.

You bet it is. But before we back it up with facts, not just claims, let’s untangle the often-muddled difference between moisturization and hydration. After all, these terms are sometimes confused - or used interchangeably - even by cosmetics manufacturers (we firmly believe it’s purely accidental, of course).
Hydration refers to replenishing water content in the skin by attracting moisture from the environment or deeper layers of the skin. Ingredients like humectants help achieve this. Moisturization, on the other hand, involves strengthening the skin’s barrier to prevent transepidermal water loss and keeping hydration locked in. Ingredients like occlusives and emollients are key players here. You simply can’t think about healthy, glowing skin without addressing both of these aspects.
As it happens, in the Fundamental Serum, we’ve included all three types of these substances, and perfecting their proportions took us the majority of our R&D time.
Let’s start with the hydrating ingredients - humectants. In the Fundamental Serum, you’ll find six types of them: Tremella Fuciformis (Snow Mushroom) Polysaccharide which has been proven to be more powerful humectant than hyaluronic acid; Yeast extract also known as plant collagen; Glycerin; Erythritol, Pentylene Glycol and Propanediol.
Equally well-represented is the group of moisturizing ingredients. In the Funamental Serum, you’ll find both occlusives and emollients working together: Ceramides, which help reinforce the skin barrier; Glycerides from almond, borage, linseed, olive acids and olives; Hibiscus Sabdariffa fruit extract, Helianthus Annuus seed oil, both occlusive and emollient Shea Butter Ethyl Esters and emollients: Squalane - which mimics the skin's natural lipids, sealing in hydration; Pentylene Glycol and Ethylhexyl Pelargonate. In short, this serum doesn’t just hydrate and moisturize - it does so with flair.

A little sneak peek into the science behind LAST and neurocosmetics is needed here (exciting!). As you know, skin and brain share their origin from the same embryologic tissue - and they even share some functions. Our central nervous system (the brain) constantly communicates with the peripheral nervous system (nerves and sensors, including skin) to synchronize external and internal “danger” signals. This communication happens through cytokines, chemokines, electric impulses, and hormones.

One fascinating example of this connection is the skin’s ability to produce cortisol in response to external stress factors. Stress, in small doses, is actually a positive evolutionary adaptation - it temporarily increases energy by triggering the release of glucose into the bloodstream, helping you fight or flee danger. However, when stress becomes chronic, it wreaks havoc on skin homeostasis. Now, what are the external stress and cortisol tiggers? Mechanical or chemical aggressions, pollution, smoke, pathogens, sleep deprivation, UV exposure… basically, all the environmental factors we’re exposed to daily, often in overwhelming amounts. Even if you lead a healthy and conscious lifestyle, you can’t fully eliminate them.

The consequences of prolonged exposure to stress and elevated cortisol levels is something we feel and see every day when we look in the mirror. When skin cells don’t stop producing cortisol, it disrupts homeostasis and leads to:

• Decreased immunity, resulting in conditions like acne and eczema
• Inflammation, causing redness, rosacea, and dark circles
• Reduced energy and detoxification, which accelerates premature aging and creates a tired, lackluster appearance
  

Thankfully, neurocosmetics - and neuroactive ingredients - can directly target cortisol in the skin, reducing its production by up to 70%. One such powerhouse ingredient in the Fundamental Serum is Tephrosia purpurea extract, which acts as a neuropeptide. In just two hours after application, this extract can reduce cortisol production by up to 70%, helping to soothe stressed skin, enhance radiance, reduce dark circles, and deliver potent anti-aging benefits, particularly for sensitive skin.

Backed by both in vitro and in vivo studies, the specific Tephrosia purpurea extract we use at LAST has demonstrated outstanding results in treating stressed, aging skin. It effectively reduces visible signs of stress and fatigue after just one month of use. Here are the clinical results we fell in love with - and couldn’t wait to deliver to you too:

• Inhibits cortisol production by up to 70% within 2 hours of application
• Increases beta-endorphin production by up to 163% in 24 hours, promoting moisturization and tissue regeneration
• Stimulates cellular stress-response proteins: Up to 3000% increase in HMOX1, the major cellular response to stress and Up to 200% increase in NQO1, the key response to oxidative stress
• Improves skin luminosity by up to 103% in just 14 days, as measured by a spectrocolorimeter in volunteers with stressed skin
• Reduces skin redness by 2.4 times in 28 days
• Dramatically diminishes dark circles and evens skin tone, with a 99% improvement in ITA angle (skin color) in just 14 days

Yes, and we swear Kate was crying at least once when we nearly lost hope of ever achieving the effectiveness we were aiming for. Thankfully, even when you step into darkness, your eyes eventually adjust, and you begin to see more. That’s exactly what happened in this case. Focused (obsessively) on creating a moisturizing cream - because that’s what you asked for most often - we didn’t consider any alternatives to the product's physicochemical form. And yet something was always wrong with this cream. Sometimes it wasn’t hydrating enough, other times it didn’t soften sufficiently, or it failed to give the skin the right radiance - either too little or too much. It was too thin, too thick, too this, too that. At one point, we spent entire weeks just trying to find a natural, clean emulsifier that could support such a high concentration of active ingredients. And we lost that battle too.
The breakthrough moment came when we abandoned the idea of a cream and decided to create a two-phase serum instead. This decision completely unblocked the process - likely most of all mentally - and suddenly, all the challenges resolved themselves almost instantly. From there, we made only a few minor refinements and created a product we were proud to send for testing by selected clinics and clients with the most demanding skin conditions. Just days into their testing, we knew: this was it. The feedback was glowing - and so were our faces as we finally saw what had once felt impossible.

Oh, there are so many! We never followed the path of creating skincare products with just a few highlighted key ingredients and a totally average or even useless remainder in terms of skin benefits. In the Fundamental Serum, every single ingredient brings outstanding value - not only due to its own effectiveness and performance but also because of the powerful synergies it creates with others.
However, if we were to list just a few key ingredients... alright, we can try to narrow it down to the top 10. But please appreciate the effort.
Our favorites, in random order:

Tremella Fuciformis Polysaccharide - extracted from the snow mushroom - has been used medicinally since at least 200 AD, and was historically reserved for royalty in ancient China. With an average molecular weight exceeding one million Daltons (>1000 kDa) it is considered a plant-based alternative to hyaluronic acid - though it offers superior moisturizing properties due to its greater water-holding capacity. Unlike hyaluronic acid, it forms a stronger protective film that does not cause skin tightening or flaking.
Tephrosia Purpurea extract, derived from the seeds of a native Indian plant, used in traditional Ayurvedic medicine is anti-inflammatory, antioxidant, and detoxifying. This extract acts as a neuropeptide, reducing cortisol (the stress hormone) production by up to 70% and increasing beta-endorphin production by up to 163% in 24 hours. It soothes the skin, enhances radiance, reduces dark circles, and provides anti-aging benefits, particularly for sensitive skin.
Shiunko fermentoil - derived from the traditional Japanese herb Lithospermum erythrorhizon, has been a key component in Kampo, traditional Japanese medicine, for treating burns, frostbite, eczema, psoriasis, and general skin irritations. Anti-inflammatory, anti-tumor, inhibiting angiogenesis. It enhances blood circulation, accelerates tissue regeneration and has been clinically shown to improve skin texture.
Yeast extract - a plant-based alternative to collagen - has been used in medicine since the 1930s for its wound healing abilities and its role in enhancing collagen synthesis. Contains a complex mixture of amino acids, peptides, carbohydrates, nucleic acids, vitamins, and minerals. In skincare, it provides moisturizing and hydrating benefits, reduces skin irritation and stimulates skin healing.
Dermo-mimetic ceramide NP, also known as Ceramide III, one of several types of ceramides naturally found in the skin. It acts as a biocompatible "cement" that bonds skin cells in a fluid, elastic mode, enhancing smoothness and elasticity. Known for its skin-repairing and moisturizing properties, it is especially valuable for treating dry, sensitive, or damaged skin. It helps restore the skin barrier, improves skin elasticity and reduces the appearance of wrinkles.
Cyanocobalamin (Vitamin B12) - produced through bacterial fermentation, vitamin B12 is essential for both the hematological and nervous systems. It is involved in red blood cell production, brain and nerve health and DNA synthesis. In the pharmaceutical industry, it has been used for years to prevent or alleviate dermatological conditions like atopic dermatitis, eczema, and psoriasis, thanks to its ability to counteract skin-irritating factors.
Arginine - an amino acid naturally present in the skin - soothing, enhancing moisture retention, supporting skin repair and improving barrier function. Its antioxidant properties help neutralize free radicals, reduce oxidative stress and promote collagen production, improving skin elasticity and reducing the appearance of fine lines and wrinkles.
Almond, borage, linseed, olive glycerides, rich in valuable essential fatty acids like oleic acid, linoleic acid, alpha-linoleic and gamma-linolenic acid, are known for their metabolic and anti-inflammatory effects. Extracted through enzymatic activation of oil, which breaks triglycerides into their constituents (fatty acids and glycerides), releasing energy and increasing antioxidant potency (+114%). They are nourishing, moisturising, increasing the elasticity of the skin, reducing stretch-marks.
Hibiscus Sabdariffa rruit extract - sourced from the Australian Wild Rosella plant, known for its exceptional drought resistance and high betaine content, this extract is perfect for mature skin, as it restores age-dependant osmolyte activity and promotes rapid and effective hydration. By stimulating organic osmolytes cellular intake, it provides osmo-hydration that addresses the root cause of skin dryness. Notably, it delivers immediate and long-lasting moisturizing effect up to 72h after single application.
Sapindus Mukorossi fruit extract - derived from the fruit of the Sapindus Mukorossi tree native to Himalayas, it is a versatile skincare ingredient celebrated for its natural cleansing properties. Rich in saponins, it acts as a natural surfactant, simultaneously offering antioxidant benefits, inhibiting free radicals and providing protection against environmental stressors.

For the full list of Fundamental Serum’s ingredients, scroll down. For more insights on the active ingredients, visit the Ingredients webpage.

At LAST, our foremost criterion in selecting active ingredients is clinical efficacy - demonstrated through robust in vitro and in vivo studies. We prioritize actives that deliver high-impact, measurable results for the specific skin function we aim to support.
For the Fundamental Serum, our focus was on deep hydration and moisture retention. Among all tested ingredients, Tremella fuciformis - commonly known as snow mushroom - consistently delivered the most impressive outcomes. With a molecular weight exceeding one million Daltons, its polysaccharides bind significantly more water than hyaluronic acid and form a protective, hydrophobic biofilm that locks in moisture longer, without the tightness or flaking often associated with hyaluronic acid (HA). Clinically, Tremella fuciformis increases skin hydration by +64.41% within just 3 hours - outperforming HA - and offers 34% free radical scavenging activity at only 0.08%, providing potent antioxidant protection. Its silky, non-shrinking finish also scored unanimously in blind sensory evaluations, where 100% of test subjects preferred it over hyaluronic acid for skin feel.
Beyond performance, Tremella fuciformis is COSMOS-certified, 100% natural, vegan, and cruelty-free - perfect and fully aligned with the values we uphold at LAST.

We appreciate the curiosity :) And yes, we’re big fans of plant-based alternatives to traditionally animal-derived ingredients - especially when they deliver superior performance on the skin!
The plant-based alternative to collagen we use in the Fundamental Serum is yeast extract: a water-soluble, botanical ingredient clinically proven to stimulate collagen synthesis and support skin regeneration. Extracted through yeast autolysis, it contains a potent mix of peptides, amino acids, nucleic acids and minerals - all of which penetrate the epidermis and upregulate cellular growth factors responsible for healing, angiogenesis and new collagen formation. In collagen assays conducted on human dermal fibroblasts, the yeast extract we use significantly increased collagen production and enhanced tensile strength and elasticity at concentrations as low as 0.01%. How could anyone resist that?

The Fundamental Serum, like all our formulations, is designed to be safe for use during pregnancy and breastfeeding, using only clinical-grade plant extractsand biomimetic molecules. It contains no known teratogens or endocrine disruptors. That said, if you're especially cautious or navigating a high-risk pregnancy, we always recommend sharing the INCI list with your healthcare provider - for your own peace of mind.
A few key points regarding the formula’s safety profile:

No retinoids, salicylic acid or other restricted actives - These are commonly contraindicated during pregnancy, and none are present in this formula.

No synthetic endocrine disruptors or harsh preservatives - The serum is free from parabens, formaldehyde releasers, phenoxyethanol etc. Instead, we use Radish Root Ferment Filtrate with Leuconostoc as a natural, skin-friendly antimicrobial.
Essential oils used in minimal, regulated concentrations - While it includes essential oils like Citrus Aurantium (bergamot), Cymbopogon Citratus (lemongrass), Lavandula Angustifolia (lavender), and Pogostemon Cablin (patchouli), they are present only in low, cosmetic-grade doses that are generally well tolerated during pregnancy - unless you have a known allergy or sensitivity.
The entire formula is built on bioavailable, skin-identical, and plant-derived actives - with no unnecessary fillers or synthetics.
No acne, pigment or exfoliating actives contraindicated in pregnancy - such as benzoyl peroxide, hydroquinone, or high-concentration AHAs.

The Fundamental Serum and the Skin Repair Serum are both advanced formulations designed to enhance skin health, yet they cater to different skin needs and concerns through distinct mechanisms and ingredient profiles.
The Skin Repair Serum is an intensive, regenerative treatment designed to address visible signs of aging, environmental damage, and cellular fatigue. Formulated for evening use, this two-phase serum focuses on repairing the skin’s deeper structures with biomimetic tetrapeptides, powerful plant extracts and Carnosine, boosting collagen synthesis and improving elasticity. Adaptogenic Rhodiola Rosea and a neurocosmetic complex help reduce cortisol levels, supporting the skin’s natural recovery rhythm. Antioxidants like oil-soluble Vitamin C and CoQ10 brighten dull complexions and counteract oxidative stress, while a rich blend of glycerides and cold-pressed oils delivers deep nourishment. It’s ideal for skin showing wrinkles, loss of firmness, uneven tone, and a depleted glow - especially in urban or aging skin.
The Fundamental Serum is your go-to for daily hydration, barrier restoration, and neuro-soothing balance. It’s formulated to address the fundamental needs of dehydrated, stressed, inflamed, or sensitized skin - think dryness, redness, under-eye darkness, and loss of radiance. Using Tremella fuciformis (a more effective alternative to hyaluronic acid), ceramides and yeast extract, it restores moisture and reinforces the skin’s barrier. Meanwhile, Tephrosia purpurea extract acts on the cutaneous nervous system, reducing cortisol and boosting beta-endorphins, which helps calm reactive skin and visibly brighten the complexion. This serum is less about repair and more about prevention, resilience, and keeping skin in a state of balanced luminosity.

The Serum’s distinctive pink hue comes from Cyanocobalamin, also known as Vitamin B12. Beyond its vibrant color, this vitamin plays a crucial role in supporting skin health, barrier function and regeneration. Clinically used in dermatology for conditions like eczema and atopic dermatitis, Vitamin B12 helps calm inflammation, enhance cell turnover, and protect the skin from environmental stressors, including UV damage. So while the pink is beautiful, it’s also functional - delivering both visual appeal and therapeutic benefit in a single drop.

Twice a day? More often if you like it? The formula won’t dehydrate your skin nor destroy your protective skin barrier.