Medik8 Daily Radiance Vitamin C Versus Medik8 C-Tetra Day Cream
Updated on May 15, 2024
Overview
What they are
These products are both vegan, cruelty-free, and reef safe day moisturizers. They have a total of 16 ingredients in common
Cool Features
They both contain hyaluronic acid, Vitamin C and Vitamin E
Suited For
They're both likely to be good for dry skin, brightening skin, reducing pores and better texture
Free From
They both do not contain any harsh alcohols, parabens or sulfates
What's Inside
They both contain common allergens, fragrances and oils
We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.
Ingredient Info
Medik8 Daily Radiance Vitamin C 33 ingredients
Medik8 C-Tetra Day Cream 26 ingredients
About this product
About this product
At a glance
Click on any of the items below to learn more
Medik8 Daily Radiance Vitamin C 33 ingredients
Medik8 C-Tetra Day Cream 26 ingredients
Key Ingredients
Benefits
Concerns
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Stay hydrated!
Learn more about WaterTetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.
THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).
Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.
Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.
Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.
A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).
While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.
THD is pretty stable, but it’s still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!
Read more about other types of Vitamin C:
Learn more about Tetrahexyldecyl AscorbateGlycerin is already naturally found in your skin. It helps moisturize and protect your skin.
A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.
As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.
Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.
Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.
In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.
This ingredient is organic, colorless, odorless, and non-toxic.
Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Learn more about GlycerinTocopheryl Acetate is AKA Vitamin E. It is an antioxidant and protects your skin from free radicals. Free radicals damage the skin by breaking down collagen.
One study found using Tocopheryl Acetate with Vitamin C decreased the number of sunburned cells.
Tocopheryl Acetate is commonly found in both skincare and dietary supplements.
Learn more about Tocopheryl AcetateDisodium EDTA plays a role in making products more stable by aiding other preservatives.
It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.
Disodium EDTA is a salt of edetic acid and is found to be safe in cosmetic ingredients.
Learn more about Disodium EDTACitrus Grandis Peel Oil is an essential oil that is derived from the peel of a Grapefruit. It is composed largely of limonene, which is a fragrance that can cause irritation for sensitive skin.
Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.
In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.
"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
Learn more about Sodium HydroxideSodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.
Like hyaluronic acid, it is great at holding water and acts as a humectant. This makes it a great skin hydrating ingredient.
Sodium Hyaluronate is naturally occurring in our bodies and is mostly found in eye fluid and joints.
These are some other common types of Hyaluronic Acid:
Learn more about Sodium HyaluronateCitrus Limon Peel Oil is created from the peels of the lemon. It is used to add a lemon-scent to products. Lemon peel oil also has antibacterial, antifungal, and antioxidant properties. However, it may also cause phototoxicity and sensitize skin.
Lemon peel oil contains limonene, a skin sensitizing ingredient. Another component is furanocoumarin, which induces phototoxicity in skin.
Furanocoumarins bind and destabilize your DNA to increase the rate of sunburn.
Most reputable companies will remove furanocoumarins from their formulations.
Learn more about Citrus Limon Peel OilCitrus Aurantium Bergamia Fruit Oil is the oil from the bergamot orange. It is native to Italy.
This ingredient is used to add fragrance to products. It contains limonene, linalool, and linalyl acetate.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
When used topically, Citrus Aurantium Bergamia Fruit Oil is a photosensitizer due to its furanocoumarins. Photosensitizers make the skin and eyes much more sensitive to sunlight. Photosensitizers are linked to skin cancer.
However, more cosmetics using Citrus Aurantium Bergamia Fruit Oil are removing the furanocoumarins.
Bergamot oil was also found to have anti-inflammatory, antibacterial and antifungal properties.
Learn more about Citrus Aurantium Bergamia Fruit OilPelargonium Graveolens Flower Oil is the pressed oil of the Rose Geranium plant. It is volatile, meaning it evaporates off the skin.
Rose Geranium contains antimicrobial, anti-inflammatory, and antioxidant properties. It has been shown to reduce bacteria and fungus. Due to these properties, Rose Geranium may help reduce acne.
The antioxidants may help reduce the signs of aging, such as fine-lines and wrinkles.
Fragrant components of Rose Geranium include citronellol and geraniol. These may cause allergies and skin-sensitivity. We recommend speaking with a professional if you have any concerns. The scent of Rose Geranium closely resembles traditional roses.
Learn more about Pelargonium Graveolens Flower OilLimonene is a fragrance that adds scent and taste to a formulation.
It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".
Limonene acts as an antioxidant, meaning it helps neutralize free radicals.
When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about LimoneneCitronellol is used to add fragrance/parfum to a product. It is often derived from plants such as roses. In fact, it can be found in many essential oils including geranium, lavender, neroli, and more. The scent of Citronellol is often described as "fresh, grassy, and citrus-like".
Since the Citronellol molecule is already unstable, Citronellol becomes irritating on the skin when exposed to air.
Citronellol is a modified terpene. Terpenes are unsaturated hydrocarbons found in plants. They make up the primary part of essential oils.
Citronellol is not able to be absorbed into deeper layers of the skin. It has low permeability,
Citronellol is also a natural insect repellent.
Learn more about CitronellolLinalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
Like Limonene, this ingredient oxidizes when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.
This ingredient has a scent that is floral, spicy tropical, and citrus-like.
Learn more about LinaloolGeraniol is used to add fragrance/parfum to a product. It is the main component of citronellol. It is a monoterpenoid and an alcohol.
Monoterpenes are naturally found in many parts of different plants.
Geraniol can be found in many essential oils including Rose Oil and Citronella Oil. The scent of Geraniol is often described as "rose-like". Many foods also contain Geraniol for fruit flavoring.
Geraniol can irritate the skin when exposed to air. However, irritation depends on the ability of geraniol to penetrate into the skin. In general, geraniol is not able to penetrate skin easily.
Geraniol is colorless and has low water-solubility. However, it is soluble in common organic solvents.
Like citronellol, it is a natural insect repellent.
2,6-Octadien-1-ol, 3,7-dimethyl-, (2E)-
Learn more about GeraniolCitral is a fragrance and used to add a lemon-like scent to products. It is both naturally found in plants and created synthetically. In plants, it is commonly occurring in lemon myrtle, lemongrass, lemon tea-tree, lemon verbena, and other citruses.
The EU mandates Citral be listed separately as a fragrance. It is a known allergen and may cause contact dermatitis. Citral can also used as a masking ingredient.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
The term 'citral' is a collective term for two geometric isomers: geranial/Citral A and neral/Citral B.
Learn more about CitralIngredient Ratings
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