Background
Vitamin A is an essential nutrient that supports vision, skin health, immunity, and cell growth. In supplements, it is often provided as beta-carotene, a plant-based precursor that the body converts into active vitamin A (retinol). For skin, vitamin A plays a critical role in collagen production, reducing wrinkles, and supporting healthy turnover of skin cells.

Origin, Source, and Traditional/Historical Use
Beta-carotene is naturally found in colorful fruits and vegetables like carrots, sweet potatoes, spinach, and kale. For centuries, diets rich in these foods were linked to healthy skin and eyesight. In modern supplements, beta-carotene is used as a safe, plant-based source of vitamin A.

Key Active Compounds and Chemical Composition
Beta-carotene (C40H56) is a carotenoid pigment. In the body, it is split by the enzyme beta-carotene 15,15’-dioxygenase into two molecules of retinal, which can then be converted to retinol (vitamin A). This active form supports skin, vision, and immune function.

Bioavailability, Absorption, and Metabolism
Beta-carotene is absorbed in the small intestine, especially when taken with dietary fat. Its absorption rate depends on individual needs—if vitamin A levels are low, conversion to retinol increases. Excess beta-carotene is stored in fat tissue and skin, sometimes giving the skin a golden glow.

Current Availability and Use
Beta-carotene supplements have been widely available since the 1970s. It is used in multivitamins, skin health formulas, and as a natural food coloring.

Clinical Features

• Skin protection: Reduces UV damage and oxidative stress, improving skin resilience within 12 weeks.
• Anti-aging: Supports collagen production, reducing wrinkle depth in clinical studies.
• Moisture balance: Improves skin hydration and texture.
• Immune support: Enhances immune defense, reducing skin infections.
• Vision health: Prevents night blindness and supports eye function.

Dosing
Typical supplement range: 3,000–9,000 mcg (5,000–15,000 IU) beta-carotene daily. Best absorbed with a meal containing fat. Available in capsules, softgels, and multivitamin blends.

Safety
Beta-carotene is considered safe, especially compared to synthetic retinol, which can be toxic at high doses. High intakes may cause carotenodermia (orange skin tint), which is harmless. Not recommended for heavy smokers at high doses due to lung health risks. Safe in pregnancy when used within RDA.

Mechanism of Action

• Collagen stimulation: Retinoids increase collagen synthesis in skin fibroblasts.
• Cell turnover: Promotes healthy keratinocyte renewal for smooth skin.
• Antioxidant activity: Neutralizes free radicals from UV exposure.
• Immune regulation: Enhances skin’s immune barrier.
• Melanin balance: Helps regulate pigmentation, supporting even skin tone.
  
  

Background
Vitamin C (ascorbic acid) is a water-soluble vitamin essential for skin, immune, and connective tissue health. It is one of the most important antioxidants in the body, protecting cells from free radical damage. For skin, vitamin C supports collagen production, brightens tone, and reduces signs of aging.

Origin, Source, and Traditional/Historical Use
Vitamin C is found naturally in citrus fruits, berries, peppers, and leafy greens. Historically, sailors carried citrus fruits to prevent scurvy, a disease caused by vitamin C deficiency. Today, ascorbic acid is widely used in supplements and skincare for its antioxidant and collagen-boosting benefits.

Key Active Compounds and Chemical Composition
Ascorbic acid (C6H8O6) is the active form of vitamin C. It acts as a reducing agent, donating electrons to neutralize free radicals. It also regenerates other antioxidants, such as vitamin E, and serves as a cofactor for collagen-producing enzymes.

Bioavailability, Absorption, and Metabolism
Vitamin C is absorbed in the small intestine through active transport and passive diffusion. Plasma levels peak within 2–3 hours of intake. Because the body does not store large amounts, regular intake is required. Excess is excreted in urine.

Current Availability and Use
Ascorbic acid supplements have been available since the 1930s. They are sold in tablets, capsules, powders, chewables, and topical serums. In skin formulas, vitamin C is a cornerstone ingredient for radiance and wrinkle prevention.

Clinical Features

• Collagen support: Clinical trials show vitamin C supplementation improves skin elasticity and reduces wrinkle depth within 3–6 months.
• Skin brightening: Reduces melanin formation, evening skin tone.
• Antioxidant defense: Protects against UV-induced oxidative damage and photoaging.
• Wound healing: Speeds skin repair by supporting connective tissue.
• Immune and skin link: Stronger immunity reduces skin inflammation and breakouts.

Dosing
RDA: 75 mg daily for women, 90 mg for men. Skin health benefits are often seen at 500–1000 mg/day. Available as ascorbic acid, buffered forms (sodium ascorbate), and liposomal vitamin C for enhanced absorption.

Safety
Vitamin C is very safe. High doses (>2000 mg/day) may cause diarrhea, nausea, or kidney stones in sensitive individuals. Safe in children and pregnancy at recommended levels.

Mechanism of Action

• Collagen synthesis: Cofactor for prolyl and lysyl hydroxylase enzymes, stabilizing collagen.
• Antioxidant activity: Neutralizes ROS (reactive oxygen species) from UV exposure.
• Melanin regulation: Inhibits tyrosinase enzyme, brightening skin tone.
• Immune modulation: Enhances white blood cell activity for skin protection.
• Vitamin E recycling: Restores oxidized vitamin E to active form, enhancing skin defense.

Background
Vitamin D₃ (cholecalciferol) is a fat-soluble vitamin that supports bone, immune, and skin health. Known as the “sunshine vitamin,” it is produced in the skin when exposed to sunlight. For skin, vitamin D₃ helps regulate cell growth, repair, and immune balance, which are essential for smooth, clear, and youthful skin.

Origin, Source, and Traditional/Historical Use
Vitamin D₃ is found naturally in fatty fish, egg yolks, and fortified dairy products. Historically, cod liver oil was used to treat rickets, a disease caused by vitamin D deficiency. Today, vitamin D₃ is the preferred supplemental form because it is identical to the vitamin D made in human skin.

Key Active Compounds and Chemical Composition
Cholecalciferol (C27H44O) is the active compound. Once in the body, it is converted in the liver to calcidiol (25-hydroxyvitamin D) and then in the kidneys to calcitriol, the active hormone form that regulates calcium, immunity, and skin cell turnover.

Bioavailability, Absorption, and Metabolism
Vitamin D₃ is absorbed in the small intestine with dietary fat and carried in the blood by vitamin D–binding protein. It has better bioavailability than vitamin D₂. The liver converts it to calcidiol, which is measured in blood tests, while the kidneys convert it to calcitriol, the active hormone.

Current Availability and Use
Vitamin D₃ supplements have been widely used since the 1930s to prevent bone disorders and improve immunity. They are available in capsules, tablets, drops, gummies, and as part of multivitamins and skin-health formulas.

Clinical Features

• Skin health: Supports epidermal cell growth and repair, reducing dryness and flakiness within 8–12 weeks.
• Anti-aging: Helps maintain skin elasticity by supporting collagen networks.
• Immune regulation: Balances immune activity, lowering risk of inflammatory skin conditions like eczema or psoriasis.
• Wound healing: Improves recovery of damaged skin tissue.
• Photoprotection: Emerging studies suggest vitamin D may protect against UV-induced DNA damage.

Dosing
RDA: 600 IU (15 mcg) daily for adults; 800 IU (20 mcg) for those over 70. For skin and immune health, 1000–2000 IU/day is commonly used. Best taken with food containing fat.

Safety
Generally safe at recommended levels. Excess (>4000 IU/day long-term) can cause hypercalcemia, with symptoms like nausea or kidney stress. Safe during pregnancy and breastfeeding at standard doses.

Mechanism of Action

• Gene regulation: Calcitriol binds to vitamin D receptors (VDR) in skin cells, influencing over 200 genes.
• Keratinocyte control: Regulates growth and differentiation of skin cells.
• Collagen support: Promotes fibroblast activity, maintaining dermal strength.
• Immune modulation: Reduces pro-inflammatory cytokines (IL-6, TNF-α).
• Barrier function: Enhances lipid production for a stronger skin barrier.

Background
Vitamin E is a fat-soluble vitamin and one of the body’s main antioxidants. In supplements, it is often provided as alpha tocopherol acetate, a stable form that protects the vitamin until it is absorbed. For skin, vitamin E helps reduce oxidative stress, protect against UV damage, and improve moisture and elasticity.

Origin, Source, and Traditional/Historical Use
Vitamin E is found naturally in nuts, seeds, vegetable oils, spinach, and avocado. It was first discovered in 1922 as an essential nutrient for reproduction and was later found to play key roles in skin and immune health. Historically, vitamin E oils have been used topically to soothe dry skin and speed wound healing.

Key Active Compounds and Chemical Composition
Alpha tocopherol (C29H50O2) is the most active form of vitamin E in humans. In supplements, the acetate form is used for better stability. Once ingested, it is converted to alpha tocopherol, which acts as a strong lipid-soluble antioxidant in skin and cell membranes.

Bioavailability, Absorption, and Metabolism
Vitamin E is absorbed in the small intestine along with dietary fats. It is transported in the blood by lipoproteins and stored mainly in fat tissue and the liver. The acetate form is converted into active vitamin E after absorption.

Current Availability and Use
Vitamin E supplements have been widely available since the 1940s. Today, it is sold in capsules, softgels, oils, creams, and included in many skin-health formulas.

Clinical Features

• UV protection: Reduces skin damage from UV rays when combined with vitamin C, with effects seen in 8–12 weeks.
• Moisture and elasticity: Improves hydration and reduces skin roughness in human trials.
• Anti-aging: Protects collagen and elastin fibers, reducing wrinkle depth.
• Wound healing: Speeds recovery of scars and minor injuries.
• Antioxidant defense: Neutralizes free radicals that accelerate skin aging.

Dosing
RDA: 15 mg (22.4 IU) daily for adults. Skin-health formulas often provide 100–400 IU daily. Best taken with food containing fat. Available in capsules, softgels, oils, and creams.

Safety
Vitamin E is generally safe. High doses (>1000 mg/day) may increase bleeding risk, especially in people taking anticoagulants. Safe in pregnancy and breastfeeding at recommended levels.

Mechanism of Action

• Antioxidant defense: Neutralizes reactive oxygen species in skin lipids.
• Collagen protection: Prevents breakdown of collagen and elastin.
• Barrier support: Strengthens the skin’s lipid layer, reducing water loss.
• Immune modulation: Enhances T-cell function, supporting skin defense.
• Synergy with vitamin C: Regenerates oxidized vitamin E, extending antioxidant activity.

Background
Riboflavin, also known as vitamin B2, is a water-soluble vitamin that plays a vital role in energy production, cellular growth, and antioxidant defense. For skin, riboflavin supports tissue repair, reduces inflammation, and helps maintain a healthy glow. It is an essential nutrient, meaning it must be obtained from food or supplements.

Origin, Source, and Traditional/Historical Use
Riboflavin is found naturally in milk, eggs, leafy greens, nuts, and whole grains. It was first identified in the 1930s as part of the vitamin B complex. Historically, diets rich in riboflavin were linked with healthy skin and resistance to cracks or sores around the mouth.

Key Active Compounds and Chemical Composition
Riboflavin (C17H20N4O6) acts as a precursor for coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These coenzymes are critical for energy metabolism, antioxidant activity, and cellular repair.

Bioavailability, Absorption, and Metabolism
Riboflavin is absorbed in the small intestine through active transport. It peaks in the bloodstream within 2–3 hours of intake. Because it is water-soluble, excess amounts are excreted in urine, often giving it a bright yellow color.

Current Availability and Use
Riboflavin supplements have been available since the 1940s and are commonly included in B-complex vitamins. It is widely used to support energy, skin, and eye health.

Clinical Features

• Skin repair: Deficiency can cause cracks at the corners of the mouth and skin irritation; supplementation helps prevent and correct these.
• Antioxidant defense: Riboflavin supports glutathione recycling, protecting skin cells from oxidative damage.
• Anti-aging: Helps reduce oxidative stress, slowing the breakdown of collagen and elastin.
• Inflammatory skin conditions: May reduce severity of acne and rosacea by lowering inflammation.
• Energy and glow: Improves cellular energy, helping skin appear healthier and more radiant.

Dosing
RDA: 1.1 mg/day for women and 1.3 mg/day for men. Skin-health formulas often provide 5–25 mg/day. Best taken with meals. Available in capsules, tablets, and multivitamins.

Safety
Riboflavin is very safe, even at higher doses, since excess is excreted. No serious side effects are reported. Safe in pregnancy, breastfeeding, and childhood at recommended intakes.

Mechanism of Action

• Energy production: FMN and FAD act in mitochondrial enzymes to fuel skin cell repair.
• Glutathione recycling: Supports antioxidant defense against UV and pollution damage.
• Collagen preservation: Reduces free radical damage to dermal proteins.
• Anti-inflammatory effects: Lowers oxidative stress signals that trigger acne and redness.
• Cell turnover: Promotes healthy keratinocyte renewal for smoother skin.

Background
Niacin, also called vitamin B3, is a water-soluble vitamin essential for energy, skin health, and nervous system function. In supplements, it is often provided as niacinamide, a form that does not cause skin flushing. For skin, niacinamide helps reduce redness, improve barrier strength, and fade dark spots.

Origin, Source, and Traditional/Historical Use
Niacin is found naturally in meats, fish, nuts, and whole grains. Pellagra, a disease caused by niacin deficiency, was first identified in the 18th century and was marked by rough skin, diarrhea, and fatigue. Supplementing with niacin or niacinamide prevented and reversed this condition, showing its importance for skin health.

Key Active Compounds and Chemical Composition
Niacinamide (C6H6N2O) is converted in the body into coenzymes NAD+ (nicotinamide adenine dinucleotide) and NADP+. These molecules fuel cellular energy production, DNA repair, and antioxidant defense in skin cells.

Bioavailability, Absorption, and Metabolism
Niacinamide is easily absorbed in the small intestine and reaches peak blood levels within 1–2 hours. It circulates in the body and is stored briefly in tissues. Excess amounts are excreted in urine, making regular intake necessary.

Current Availability and Use
Niacinamide supplements and topical serums have become very popular in dermatology and skincare. It is widely available in multivitamins, B-complex products, and skin-health formulas.

Clinical Features

• Barrier repair: Improves ceramide and fatty acid production, strengthening the skin barrier within 4–8 weeks.
• Redness reduction: Clinical studies show niacinamide reduces inflammation and redness in acne and rosacea.
• Anti-aging: Increases collagen and elastin, reducing fine lines and wrinkles in 12 weeks.
• Skin brightening: Inhibits melanin transfer, helping fade hyperpigmentation.
• Antioxidant defense: Protects against UV-induced oxidative stress when combined with sunscreen.

Dosing
RDA: 14 mg/day for women, 16 mg/day for men. For skin benefits, supplements typically provide 50–500 mg/day. Available in capsules, tablets, multivitamins, and topical creams or serums.

Safety
Niacinamide is safe at recommended doses. Very high oral doses (>1000 mg/day) may cause nausea or liver stress. Unlike niacin, niacinamide does not cause flushing. Safe during pregnancy, breastfeeding, and for children at dietary levels.

Mechanism of Action

• NAD+/NADP+ production: Fuels cellular energy and DNA repair.
• Barrier strengthening: Stimulates ceramide and lipid synthesis in the skin.
• Collagen protection: Reduces glycation and oxidative damage to dermal proteins.
• Anti-inflammatory: Lowers cytokines (IL-6, TNF-α) linked to acne and redness.
• Melanin regulation: Blocks pigment transfer from melanocytes to skin cells.

Background
Vitamin B12 is a water-soluble vitamin essential for red blood cell formation, nervous system function, and DNA synthesis. In supplements, it is often provided as methylcobalamin, the active form that is easily used by the body. For skin, vitamin B12 supports cell renewal, oxygen delivery, and healthy pigmentation, all of which contribute to a youthful appearance.

Origin, Source, and Traditional/Historical Use
Vitamin B12 is naturally found in animal-based foods such as fish, meat, eggs, and dairy. Since it is not present in plants, deficiencies are more common in vegetarians and vegans. B12 was first discovered in the 1940s as the key nutrient preventing pernicious anemia, a condition that causes fatigue and pale, unhealthy-looking skin.

Key Active Compounds and Chemical Composition
Methylcobalamin (C63H91CoN13O14P) is one of the active coenzyme forms of vitamin B12. It contains cobalt at its center and is critical for two main enzyme reactions: methionine synthase (DNA and protein production) and methylmalonyl-CoA mutase (energy metabolism).

Bioavailability, Absorption, and Metabolism
Vitamin B12 is absorbed in the small intestine with the help of intrinsic factor, a protein made in the stomach. Methylcobalamin has higher bioavailability than synthetic cyanocobalamin, as it does not require conversion. Once absorbed, it is stored in the liver and can last for years.

Current Availability and Use
Methylcobalamin supplements are widely available in capsules, tablets, sprays, and sublingual forms. It is often included in B-complex formulas and skin-health supplements.

Clinical Features

• Skin tone and glow: Deficiency can cause pale or dull skin; supplementation restores healthy color within weeks.
• Anti-aging: Supports DNA synthesis and repair, reducing cellular damage linked to wrinkles.
• Oxygen delivery: Improves circulation and nutrient transport to skin tissues.
• Pigmentation balance: Helps regulate melanin and reduce uneven skin tone.
• Wound healing: Supports faster recovery of skin injuries through enhanced cell turnover.

Dosing
RDA: 2.4 mcg/day for adults. Supplements often provide higher doses (500–2000 mcg) to improve absorption, especially in older adults. Best taken sublingually or with food.

Safety
Vitamin B12 is very safe, with no known toxicity even at high doses. Rare side effects include mild acne or rosacea flare-ups in sensitive individuals. Safe for children, pregnancy, and breastfeeding at recommended amounts.

Mechanism of Action

• DNA synthesis: Supports rapid turnover of skin cells.
• Methionine pathway: Helps recycle homocysteine into methionine, supporting collagen production.
• Red blood cell formation: Improves oxygen delivery to skin and hair follicles.
• Nervous system support: Reduces stress-related effects on skin health.
• Antioxidant activity: Protects against oxidative damage in skin tissues.

Background
Biotin, also known as vitamin B7, is a water-soluble vitamin that plays a major role in energy metabolism and the production of keratin, the main protein in skin, hair, and nails. It is often called the “beauty vitamin” because of its connection to healthy skin glow, strong nails, and fuller hair.

Origin, Source, and Traditional/Historical Use
Biotin is naturally found in foods like eggs, nuts, seeds, salmon, and leafy greens. It was first identified in the 1930s, when scientists linked deficiency to skin rashes, hair loss, and brittle nails. Historically, diets rich in biotin-containing foods were associated with healthy skin and strong nails.

Key Active Compounds and Chemical Composition
Biotin (C10H16N2O3S) acts as a coenzyme for carboxylase enzymes. These enzymes are important for fatty acid synthesis, glucose metabolism, and amino acid breakdown—processes that fuel skin cell growth and keratin production.

Bioavailability, Absorption, and Metabolism
Biotin is absorbed in the small intestine through active transport. It is stored in small amounts in the liver and excreted in urine, so regular intake is necessary. The body also receives biotin from gut bacteria that produce it naturally.

Current Availability and Use
Biotin has become a popular supplement for skin, hair, and nail support. It is widely available as capsules, tablets, gummies, and included in beauty-focused formulas.

Clinical Features

• Skin glow: Biotin deficiency causes rashes, dryness, and dull skin, which improve quickly with supplementation.
• Keratin support: Increases keratin production, improving skin texture, nail strength, and hair growth.
• Nail health: Clinical trials show biotin strengthens brittle nails, improving hardness and thickness within 6–9 months.
• Hair benefits: Helps reduce thinning and shedding in people with low biotin levels.
• Metabolic support: Improves fat and amino acid metabolism, fueling skin cell renewal.

Dosing
RDA: 30 mcg/day for adults. Supplements for skin, hair, and nails often provide 2,500–10,000 mcg daily. Available in capsules, tablets, and gummies.

Safety
Biotin is very safe, even at high doses. It is water-soluble, so excess is excreted. No major side effects are known. Very high doses may interfere with certain lab tests (e.g., thyroid or heart markers). Safe in pregnancy and breastfeeding at recommended levels.

Mechanism of Action

• Keratin production: Supports structural proteins in skin, hair, and nails.
• Energy metabolism: Acts as a cofactor for enzymes producing cellular energy.
• Fatty acid synthesis: Fuels lipid production for healthy skin barrier.
• Gene regulation: Influences expression of keratin-related genes.
• Microbiome contribution: Works with gut bacteria that supply biotin naturally.

Background

Pantothenic acid, also known as vitamin B5, is a water-soluble vitamin that is essential for making coenzyme A, a molecule needed for energy metabolism and fatty acid production. For skin, pantothenic acid supports wound healing, reduces acne, and helps maintain a strong skin barrier.

Origin, Source, and Traditional/Historical Use
The name “pantothenic” comes from the Greek word pantothen, meaning “from everywhere,” since this vitamin is found in almost all foods. Rich sources include eggs, whole grains, mushrooms, chicken, and avocados. In the mid-20th century, researchers discovered its role in skin healing and adrenal function.

Key Active Compounds and Chemical Composition
Pantothenic acid (C9H17NO5) is converted in the body into coenzyme A (CoA), which is essential for fatty acid metabolism, energy production, and the synthesis of hormones and skin lipids.

Bioavailability, Absorption, and Metabolism
Pantothenic acid is absorbed in the small intestine through active transport. Once in the bloodstream, it is widely distributed to tissues. The body uses it to create CoA, which drives metabolic reactions in skin cells. Excess amounts are excreted in urine.

Current Availability and Use
Pantothenate is available in capsules, tablets, powders, and multivitamins. It is often used in skin-health supplements and topical creams, where it appears as panthenol, a form that hydrates and soothes the skin.

Clinical Features

• Acne reduction: Studies show supplementation with 2.5 g/day significantly reduced acne lesions within 12 weeks.
• Skin healing: Speeds repair of wounds and minor skin injuries by boosting cell regeneration.
• Barrier function: Supports fatty acid and lipid production, strengthening the skin barrier.
• Anti-aging: Improves skin elasticity and hydration through enhanced lipid metabolism.
• Stress support: By aiding adrenal hormone production, it may help regulate stress-related skin issues.

Dosing
RDA: 5 mg/day for adults. For skin health, higher doses (100–1000 mg/day) are sometimes used in supplements. Available in oral capsules, multivitamins, and topical creams (panthenol).

Safety
Pantothenic acid is very safe, even at high doses. Very large doses may cause mild diarrhea or stomach upset. Safe for use during pregnancy, breastfeeding, and childhood at recommended levels.

Mechanism of Action

• CoA synthesis: Provides coenzyme A, critical for fatty acid and energy metabolism.
• Barrier strengthening: Enhances lipid production for healthy, hydrated skin.
• Collagen support: Improves fibroblast activity and tissue repair.
• Anti-inflammatory: Reduces inflammatory cytokines in acne-prone skin.
• Cell turnover: Encourages rapid skin regeneration and wound healing.

Background
Zinc is an essential trace mineral that supports immunity, wound healing, and skin health. In supplements, it is often provided as zinc picolinate, a form with high absorption. For skin, zinc helps control oil production, reduces acne, and supports tissue repair.

Origin, Source, and Traditional/Historical Use
Zinc is naturally found in oysters, beef, poultry, beans, seeds, and nuts. Its importance was first recognized in the 1960s, when zinc deficiency was linked to delayed growth, poor wound healing, and skin rashes. Traditionally, zinc-based ointments were used to treat wounds and skin irritation.

Key Active Compounds and Chemical Composition
Zinc picolinate is zinc bound to picolinic acid, which improves absorption in the intestine. Zinc itself is a cofactor for over 300 enzymes that regulate protein synthesis, cell growth, and immune balance—all essential for skin renewal.

Bioavailability, Absorption, and Metabolism
Zinc picolinate has been shown in studies to be more bioavailable than other forms like zinc citrate or gluconate. Once absorbed, zinc is distributed to tissues, especially skin, hair, and nails. Excess amounts are excreted in urine and stool.

Current Availability and Use
Zinc picolinate has been widely available since the 1980s and is often used in immune, skin, and hair supplements. It is sold in capsules, tablets, and multivitamin blends.

Clinical Features

• Acne reduction: Clinical trials show zinc reduces acne lesions by 30–50% within 8–12 weeks.
• Wound healing: Speeds skin repair by supporting collagen and tissue formation.
• Oil control: Regulates sebaceous gland activity, reducing clogged pores.
• Anti-inflammatory: Lowers cytokines that trigger redness and irritation.
• UV protection: Acts as an antioxidant, reducing free radical damage from sunlight.

Dosing
RDA: 8 mg/day for women, 11 mg/day for men. Skin-health supplements often provide 15–30 mg/day of zinc picolinate. Best taken with food to prevent nausea.

Safety
Generally safe at recommended doses. Taking more than 40 mg/day long-term may cause copper deficiency, nausea, or weakened immunity. Safe during pregnancy and breastfeeding at RDA levels.

Mechanism of Action

• Enzyme cofactor: Supports enzymes involved in collagen synthesis and repair.
• Oil regulation: Balances activity of sebaceous glands.
• Anti-inflammatory: Reduces IL-6 and TNF-α, calming acne-prone skin.
• Immune defense: Enhances white blood cell function to fight skin infections.
• Antioxidant: Stabilizes cell membranes and reduces oxidative stress.

Background
Selenium is an essential trace mineral that plays a powerful role in antioxidant defense, thyroid function, and immune balance. In supplements, it is often provided as sodium selenate, a stable and well-absorbed form. For skin, selenium protects against oxidative stress, supports elasticity, and helps reduce UV-related damage.

Origin, Source, and Traditional/Historical Use
Selenium is found naturally in Brazil nuts, seafood, eggs, and whole grains. Its importance for health was first discovered in the 1950s, when deficiencies were linked to poor growth, immune weakness, and skin issues. In traditional diets, selenium-rich foods were often tied to long-lasting vitality.

Key Active Compounds and Chemical Composition
Sodium selenate (Na2SeO4) delivers selenium in a form the body can easily use. Selenium is incorporated into selenoproteins, such as glutathione peroxidase, which protect cells from oxidative damage and regulate inflammation.

Bioavailability, Absorption, and Metabolism
Selenium from sodium selenate is absorbed in the small intestine with high efficiency. Once in the bloodstream, it is used to form selenocysteine, the active amino acid that is built into selenoproteins. These proteins act as antioxidants and metabolic regulators.

Current Availability and Use
Selenium supplements have been widely available since the 1970s and are often included in multivitamins, antioxidant blends, and skin-health formulas.

Clinical Features

• UV protection: Selenium combined with vitamin E reduces skin redness and DNA damage from sun exposure within 8–12 weeks.
• Anti-aging: Improves skin elasticity by reducing oxidative stress in dermal tissues.
• Acne and inflammation: Helps calm inflamed skin by lowering free radicals.
• Wound healing: Supports tissue repair through antioxidant enzymes.
• Thyroid and skin link: Selenium supports thyroid hormones, which regulate skin hydration and turnover.

Dosing
RDA: 55 mcg/day for adults. Supplements for skin and antioxidant support usually provide 100–200 mcg/day. Best taken with food.

Safety
Safe at recommended levels. Chronic intake above 400 mcg/day may cause selenosis, with symptoms like brittle hair, nail changes, and stomach upset. Safe in pregnancy and breastfeeding at RDA levels.

Mechanism of Action

• Antioxidant defense: Cofactor for glutathione peroxidase, which neutralizes ROS (reactive oxygen species).
• Collagen protection: Prevents oxidative breakdown of skin proteins.
• Immune balance: Regulates cytokines, reducing skin inflammation.
• DNA protection: Lowers UV-induced mutations in skin cells.

Thyroid regulation: Supports enzymes that activate thyroid hormones, indirectly improving skin tone and hydration.

Background
Milk thistle (Silybum marianum) is a flowering plant native to the Mediterranean region. Its seeds are rich in silymarin, a group of antioxidant compounds that protect the liver, reduce inflammation, and support skin health. For skin, milk thistle helps neutralize free radicals, improve detoxification, and maintain a clearer, more radiant complexion.

Origin, Source, and Traditional/Historical Use
Milk thistle has been used for over 2,000 years in traditional European and Middle Eastern medicine. Historically, it was taken as a liver tonic to treat poisoning, jaundice, and digestive issues. Modern supplements focus on standardized extracts containing 70–80% silymarin.

Key Active Compounds and Chemical Composition
The main active compounds are flavonolignans, including silybin, silydianin, and silychristin. These act as strong antioxidants, membrane stabilizers, and liver protectors. Together, they help the body manage toxins and oxidative stress that can damage skin cells.

Bioavailability, Absorption, and Metabolism
Silymarin has moderate bioavailability, but absorption improves when taken with food or in enhanced formulations (e.g., phospholipid complexes). Once absorbed, it is metabolized in the liver and circulated to tissues, including skin.

Current Availability and Use
Milk thistle extract has been widely available since the 1970s and is commonly included in liver-support, detox, and skin-health supplements. It is sold in capsules, tablets, teas, and tinctures.

Clinical Features

• Skin clarity: Reduces oxidative stress and inflammation linked to acne and dullness, with improvements seen after 8–12 weeks.
• UV protection: Protects skin cells from sun-induced oxidative damage.
• Anti-aging: Reduces breakdown of collagen and elastin, helping skin stay firm.
• Detoxification: Supports liver function, indirectly improving skin tone and glow.
• Wound healing: Animal studies show improved repair of skin injuries.

Dosing
Common dose: 200–400 mg/day of standardized extract (70–80% silymarin), divided into 2–3 doses. Best taken with meals for absorption.

Safety
Milk thistle is generally safe and well tolerated. Mild side effects may include stomach upset or diarrhea. Safe in pregnancy and breastfeeding when used in dietary amounts, but high-dose supplements should be used with caution. People allergic to ragweed, daisies, or marigolds may also react.

Mechanism of Action

• Antioxidant: Scavenges free radicals and boosts glutathione levels.
• Liver support: Improves detoxification, reducing buildup of skin-dulling toxins.
• Collagen protection: Inhibits enzymes that break down collagen and elastin.
• Anti-inflammatory: Reduces cytokines like TNF-α and IL-6.
• Cell repair: Stabilizes cell membranes and promotes regeneration.

Background
Polypodium leucotomos is a tropical fern native to Central and South America. Its leaf extract has powerful antioxidant and photoprotective properties, meaning it helps protect skin from UV damage and oxidative stress. For skin health, it is best known for reducing sunburn, slowing photoaging, and improving conditions like melasma and psoriasis.

Origin, Source, and Traditional/Historical Use
The fern has been used in traditional Central American medicine for centuries to treat skin problems, inflammation, and respiratory issues. Modern research began in Spain in the late 20th century, leading to its use as an oral supplement for skin photoprotection and dermatology support.

Key Active Compounds and Chemical Composition
The extract contains phenolic compounds such as caffeic acid, ferulic acid, vanillic acid, and chlorogenic acid. These act as antioxidants and anti-inflammatories, protecting skin cells from free radicals and UV-induced DNA damage.

Bioavailability, Absorption, and Metabolism
After oral intake, its phenolic acids are absorbed in the intestine and circulate in the blood, where they reach skin tissues. They act quickly, with protective effects observed within 1–2 hours of dosing, and are metabolized by the liver before excretion.

Current Availability and Use
Polypodium leucotomos extract is sold in capsules and tablets worldwide as a sun-protective supplement. It is often included in dermatology formulas for anti-aging, pigmentation, and inflammatory skin conditions.

Clinical Features

• UV protection: Human trials show reduced sunburn and DNA damage after 240–480 mg/day, with effects seen within 60 days.
• Anti-aging: Improves elasticity and reduces wrinkle depth by protecting collagen from UV breakdown.
• Pigmentation balance: Helps lighten melasma and hyperpigmentation.
• Inflammatory skin conditions: Improves psoriasis and atopic dermatitis by lowering immune overreaction.
• Photodermatoses: Prevents flare-ups of sun-sensitive skin disorders.

Dosing
Typical oral dose: 240–480 mg daily, often divided into 2 doses. Best taken before sun exposure for photoprotection.

Safety
Well tolerated in studies, even at high doses. Mild side effects may include stomach upset or itching. Safe for long-term use. Not recommended for children under 3 years without medical advice.

Mechanism of Action

• Antioxidant defense: Neutralizes ROS (reactive oxygen species) from UV exposure.
• DNA protection: Prevents UV-induced mutations in skin cells.
• Collagen preservation: Inhibits matrix metalloproteinases (MMPs) that break down collagen.
• Immune modulation: Reduces overactive immune responses in psoriasis and dermatitis.
• Pigment regulation: Lowers oxidative stress in melanocytes, balancing melanin production.

Background
Green tea (Camellia sinensis) is one of the most widely studied plants for health and longevity. Its leaf extract is rich in antioxidants, particularly epigallocatechin gallate (EGCG), which protects cells from oxidative damage. For skin, green tea supports anti-aging, reduces inflammation, and helps maintain an even skin tone.

Origin, Source, and Traditional/Historical Use
Green tea has been consumed in China and Japan for over 4,000 years for vitality, mental focus, and disease prevention. Topically, green tea leaves were used in traditional medicine to soothe wounds and skin irritation. Modern supplements extract and standardize catechins, especially EGCG, for consistent potency.

Key Active Compounds and Chemical Composition
The main active compounds are catechins, including EGCG, epicatechin, epigallocatechin, and epicatechin gallate. EGCG is the most powerful, with strong antioxidant, anti-inflammatory, and anti-carcinogenic effects.

Bioavailability, Absorption, and Metabolism
Catechins are absorbed in the small intestine, but EGCG has limited bioavailability. Absorption improves when taken without dairy and with vitamin C. Once absorbed, catechins circulate in the blood and reach the skin, where they help protect against UV and pollution damage.

Current Availability and Use
Green tea extract is widely sold as capsules, tablets, and powders. It is also used in skincare products for its soothing and protective effects. Standardized extracts ensure high levels of EGCG for consistent results.

Clinical Features

• Anti-aging: Human studies show reduced wrinkle depth and improved skin elasticity after 12 weeks of supplementation.
• UV protection: Oral and topical use lowers sunburn response and DNA damage.
• Acne support: EGCG helps regulate sebum production and reduce inflammation.
• Skin tone: Inhibits melanin formation, helping reduce dark spots and pigmentation.
• Antioxidant defense: Neutralizes ROS, protecting collagen and elastin from breakdown.

Dosing
Typical oral dose: 250–500 mg/day of standardized extract (50% EGCG). Topical creams and serums often contain 2–5% green tea extract. Best taken between meals for absorption.

Safety
Generally safe at recommended levels. High doses (>800 mg/day EGCG) may cause liver stress in rare cases. Should be avoided with stimulant medications due to mild caffeine content. Safe in pregnancy and breastfeeding at dietary intakes.

Mechanism of Action

• Antioxidant: EGCG neutralizes ROS that age skin.
• Collagen preservation: Inhibits matrix metalloproteinases (MMPs) that degrade collagen.
• Anti-inflammatory: Reduces NF-κB signaling and pro-inflammatory cytokines.
• Sebum regulation: Lowers activity of 5-alpha reductase, reducing oil production.
• Melanin control: Blocks tyrosinase enzyme, balancing skin pigmentation.

Background
Grape seed extract is derived from the seeds of red grapes and is one of the richest natural sources of oligomeric proanthocyanidins (OPCs). These are powerful antioxidants that protect the skin from free radical damage, support collagen, and improve circulation. For skin, grape seed extract helps reduce wrinkles, improve elasticity, and brighten tone.

Origin, Source, and Traditional/Historical Use
Grape seeds have been used for centuries in Mediterranean diets, especially through wine and grape consumption. In the 20th century, scientists identified OPCs in grape seeds as potent antioxidants, leading to their use in supplements for cardiovascular and skin health.

Key Active Compounds and Chemical Composition
The extract contains 95% OPCs, a type of flavonoid. OPCs stabilize collagen and elastin, strengthen blood vessels, and act as strong antioxidants—50 times more powerful than vitamin E and 20 times stronger than vitamin C in some studies.

Bioavailability, Absorption, and Metabolism
OPCs are absorbed in the small intestine and circulate in the bloodstream within 2–3 hours. They reach the skin, where they help protect against UV damage and oxidative stress. The body metabolizes them into phenolic acids before excretion.

Current Availability and Use
Grape seed extract has been available since the 1980s and is sold in capsules, tablets, and powders. It is a common ingredient in skin-health and anti-aging supplements.

Clinical Features

• Anti-aging: Clinical trials show grape seed extract improves skin elasticity and reduces wrinkle depth within 12 weeks.
  
  
• Collagen protection: Prevents breakdown of collagen and elastin, helping skin stay firm.
  
  
• Skin brightening: Reduces melanin production, improving hyperpigmentation and dark spots.
  
  
• UV protection: OPCs lower sun-induced oxidative stress and DNA damage.
  
  
• Circulation support: Strengthens capillaries, improving oxygen and nutrient delivery to skin.
  
  

Dosing
Typical daily dose: 100–300 mg standardized extract (95% OPCs). Best taken with food.

Safety
Grape seed extract is generally safe. Mild side effects may include nausea or headache. It may increase bleeding risk in people taking blood thinners. Safe in pregnancy and breastfeeding when consumed in food amounts; supplements should be used with medical advice.

Mechanism of Action

• Antioxidant defense: OPCs neutralize ROS and regenerate vitamins C and E.
  
  
• Collagen stabilization: Binds to collagen fibers, making them more resistant to breakdown.
  
  
• Anti-inflammatory: Reduces cytokines like IL-1β and TNF-α in skin tissues.
  
  
• Melanin regulation: Inhibits tyrosinase, reducing pigmentation.
  
  
• Vascular support: Enhances nitric oxide production, improving microcirculation in skin.
  
  

Background
Alpha lipoic acid (ALA) is a naturally occurring compound made in small amounts by the body and also found in certain foods. It is both water- and fat-soluble, allowing it to work in nearly every cell. For skin, ALA helps reduce wrinkles, improve texture, and protect against oxidative stress that accelerates aging.

Origin, Source, and Traditional/Historical Use
ALA was first discovered in the 1950s as a key cofactor for mitochondrial enzymes involved in energy production. Food sources include spinach, broccoli, tomatoes, and organ meats. While not part of traditional remedies, it has been used since the 1980s as a therapeutic antioxidant in Europe.

Key Active Compounds and Chemical Composition
ALA (C8H14O2S2) exists in two forms: R-ALA (natural, biologically active) and S-ALA (synthetic). It is converted in the body to dihydrolipoic acid (DHLA), another powerful antioxidant. Together, they recycle vitamins C and E and support glutathione, the body’s master antioxidant.

Bioavailability, Absorption, and Metabolism
ALA is absorbed in the small intestine, with peak levels in the blood within 30–60 minutes of intake. Bioavailability ranges from 30–40%, but stabilized R-ALA supplements improve absorption. It is metabolized in the liver and excreted mainly in urine.

Current Availability and Use
ALA is sold worldwide in capsules, tablets, and topical creams. It is included in skin, anti-aging, and metabolic health supplements.

Clinical Features

• Anti-aging: Human studies show ALA cream reduced fine lines and improved skin texture in 12 weeks.
• Antioxidant defense: Neutralizes free radicals that damage collagen and elastin.
• UV protection: Reduces skin redness and inflammation caused by sun exposure.
• Skin tone: Supports even pigmentation by lowering oxidative stress in melanocytes.
• Circulation support: Enhances microcirculation, improving nutrient delivery to skin.

Dosing
Typical oral dose: 300–600 mg/day for antioxidant support. For skin health, topical formulations use 3–5% ALA. Best taken on an empty stomach for absorption.

Safety
Generally safe at recommended doses. High doses may cause mild nausea, rash, or dizziness. Safe in adults; limited data in pregnancy and breastfeeding, so supplementation should be supervised. People with diabetes should monitor blood sugar, as ALA may enhance insulin sensitivity.

Mechanism of Action

• Antioxidant activity: Neutralizes ROS (reactive oxygen species) in both water- and fat-soluble environments.
• Vitamin recycling: Restores oxidized vitamin C, vitamin E, and glutathione.
• Collagen protection: Inhibits enzymes (MMPs) that degrade collagen.
• Mitochondrial support: Enhances ATP production, fueling skin cell repair.
• Anti-inflammatory: Reduces NF-κB activation and pro-inflammatory cytokines.

Background
Pomegranate (Punica granatum) is a fruit rich in antioxidants, polyphenols, and vitamins that protect the skin from damage and aging. Its extract is widely studied for improving elasticity, reducing inflammation, and protecting against UV stress. For skin, pomegranate helps promote radiance, even tone, and firmness.

Origin, Source, and Traditional/Historical Use
Native to the Middle East and South Asia, pomegranate has been cultivated for over 3,000 years. In ancient Persian, Indian, and Mediterranean medicine, it was used to treat infections, digestive issues, and skin conditions. Today, pomegranate fruit extract is standardized for polyphenols to ensure consistent skin-health benefits.

Key Active Compounds and Chemical Composition
Pomegranate extract contains ellagic acid, punicalagins, anthocyanins, flavonoids, and vitamin C. These compounds act as antioxidants, anti-inflammatories, and collagen protectors. Ellagic acid and punicalagins are especially powerful in reducing UV-induced skin damage.

Bioavailability, Absorption, and Metabolism
Polyphenols in pomegranate are absorbed in the intestine and metabolized into urolithins by gut bacteria. These metabolites circulate in the blood and reach skin tissues, where they provide antioxidant and anti-aging benefits.

Current Availability and Use
Pomegranate extract is sold in capsules, tablets, and powders, as well as in topical creams and serums. It is commonly included in anti-aging and skin-brightening supplements.

Clinical Features

• Anti-aging: Human studies show pomegranate extract improves skin firmness and elasticity within 12 weeks.
  
  
• UV protection: Reduces oxidative stress and sun-induced DNA damage.
• Brightening: Ellagic acid helps reduce hyperpigmentation and dark spots.
• Hydration: Improves moisture retention by supporting skin lipids.
• Wound healing: Promotes fibroblast activity and skin repair.

Dosing
Typical oral dose: 250–500 mg/day of standardized fruit extract. Topical formulations often use 0.5–5% extract in creams or serums.

Safety
Generally safe and well tolerated. Rare side effects may include mild stomach upset. Safe in pregnancy and breastfeeding at dietary levels, though concentrated extracts should be used with medical advice.

Mechanism of Action

• Antioxidant defense: Punicalagins and ellagic acid neutralize ROS and protect DNA.
• Collagen support: Inhibits collagen-degrading enzymes (MMPs), helping skin stay firm.
• Melanin regulation: Ellagic acid blocks tyrosinase, reducing hyperpigmentation.
• Anti-inflammatory: Lowers cytokines such as IL-6 and TNF-α.
• Moisture support: Improves ceramide and lipid balance in the skin barrier.

Background
Astaxanthin is a red-orange carotenoid pigment found in microalgae, salmon, shrimp, and krill. It is one of the most powerful natural antioxidants, known to be much stronger than vitamin C or vitamin E. For skin, astaxanthin supports elasticity, reduces wrinkles, and protects against UV-induced aging.

Origin, Source, and Traditional/Historical Use
Astaxanthin is mainly derived from the freshwater microalga Haematococcus pluvialis. Historically, humans consumed it indirectly by eating salmon and shellfish, which accumulate the pigment. In Japan, astaxanthin-rich algae have been used in traditional foods, but modern supplements extract and concentrate it for skin and eye health.

Key Active Compounds and Chemical Composition
Astaxanthin (C40H52O4) is a xanthophyll carotenoid. Its unique structure allows it to span across cell membranes, protecting both the inner and outer layers from oxidative damage.

Bioavailability, Absorption, and Metabolism
Astaxanthin is fat-soluble and best absorbed with dietary oils. After absorption in the small intestine, it is transported by lipoproteins and distributed to tissues, including skin. Studies show it accumulates in skin layers, where it provides long-lasting antioxidant protection.

Current Availability and Use
Astaxanthin has been commercially available since the 1990s. It is sold in capsules, softgels, and functional foods. It is widely used in anti-aging, skin-brightening, and eye-health supplements.

Clinical Features

• Anti-aging: Clinical trials show astaxanthin reduces wrinkle depth and improves elasticity after 6–12 weeks.
• UV protection: Lowers sunburn risk and DNA damage from UV exposure.
• Skin hydration: Improves moisture levels and smoothness.
• Pigmentation balance: Helps reduce dark spots and uneven tone.
• Antioxidant defense: Proven to be 6000 times stronger than vitamin C against singlet oxygen damage.

Dosing
Typical oral dose: 4–12 mg/day. For skin health, most studies use 6 mg/day for 8–12 weeks. Best taken with meals containing fat for absorption.

Safety
Astaxanthin is considered very safe. Mild side effects may include orange discoloration of the skin at very high intakes, which is harmless. Safe for long-term use, but more research is needed in pregnancy and breastfeeding.

Mechanism of Action

• Antioxidant shield: Neutralizes ROS and singlet oxygen in skin cells.
• Collagen support: Inhibits enzymes (MMPs) that break down collagen and elastin.
• Anti-inflammatory: Reduces cytokines like IL-1β and TNF-α, calming skin irritation.
• Photoprotection: Accumulates in skin, blocking UV-induced oxidative stress.
• Membrane protection: Stabilizes cell membranes by spanning both lipid and water layers.

Background
Lycopene is a bright red carotenoid pigment found in tomatoes, watermelon, pink grapefruit, and other red fruits. It is a strong antioxidant that protects cells from oxidative damage. For skin, lycopene helps reduce wrinkles, protect against UV damage, and maintain an even, radiant complexion.

Origin, Source, and Traditional/Historical Use
Lycopene has been consumed for centuries through diets rich in tomatoes and other red fruits. The Mediterranean diet, high in tomato-based foods, has long been linked to healthy skin and lower signs of aging. Modern supplements extract lycopene from tomatoes for concentrated antioxidant support.

Key Active Compounds and Chemical Composition
Lycopene (C40H56) is a carotenoid but unlike beta-carotene, it cannot be converted into vitamin A. Its antioxidant capacity comes from its 11 conjugated double bonds, which efficiently neutralize free radicals and protect skin lipids, proteins, and DNA.

Bioavailability, Absorption, and Metabolism
Lycopene is fat-soluble and better absorbed when consumed with oils. Cooking tomatoes in oil enhances its bioavailability. After absorption, it circulates in lipoproteins and accumulates in tissues, especially skin, where it provides UV protection.

Current Availability and Use
Lycopene supplements have been available since the 1990s. They are sold in capsules, softgels, and multivitamins, often marketed for skin, eye, and cardiovascular health.

Clinical Features

• UV protection: Human studies show lycopene reduces sunburn intensity by ~40% after 10–12 weeks of supplementation.
• Anti-aging: Improves skin texture and elasticity by protecting collagen.
• Even tone: Helps reduce hyperpigmentation and brighten skin.
• Antioxidant defense: Neutralizes ROS, protecting against photoaging.
• Moisture support: Linked to better hydration and reduced roughness.

Dosing
Typical oral dose: 5–15 mg/day. For skin protection, many clinical trials use 10 mg/day for 8–12 weeks. Best taken with meals containing fat.

Safety
Lycopene is very safe. Very high doses may cause a harmless skin discoloration (orange tint). No major side effects are reported. Safe for pregnancy, breastfeeding, and children at dietary levels.

Mechanism of Action

• Antioxidant shield: Quenches singlet oxygen and neutralizes ROS.
• Collagen protection: Prevents breakdown by blocking matrix metalloproteinases (MMPs).
• UV defense: Reduces DNA and lipid damage from sunlight.
• Anti-inflammatory: Lowers cytokines like IL-1β and TNF-α.
• Skin pigmentation: Regulates oxidative stress in melanocytes, balancing melanin.

Background
Lutein is a yellow-orange carotenoid from the xanthophyll family. It is best known for supporting eye health, but research shows it also benefits skin by protecting against UV damage, improving hydration, and reducing wrinkles. As a strong antioxidant, lutein helps keep skin radiant and youthful.

Origin, Source, and Traditional/Historical Use
Lutein is naturally found in leafy greens (spinach, kale), corn, egg yolks, and marigold flowers. For centuries, diets rich in these foods were associated with healthy eyes and skin. Modern supplements extract lutein, often from marigold petals, and standardize it for consistent antioxidant benefits.

Key Active Compounds and Chemical Composition
Lutein (C40H56O2) is a fat-soluble carotenoid. Unlike beta-carotene, it cannot be converted to vitamin A. Its structure allows it to filter high-energy blue light and neutralize reactive oxygen species (ROS), which damage skin and eyes.

Bioavailability, Absorption, and Metabolism
Lutein is absorbed in the small intestine with dietary fats and transported in the blood by lipoproteins. It accumulates in the skin and eyes, especially in the macula. Bioavailability improves when taken with oils or in softgel formulations.

Current Availability and Use
Lutein supplements have been widely available since the 1990s and are often included in eye- and skin-health formulas. It is sold in capsules, softgels, and powders, usually combined with zeaxanthin or other carotenoids.

Clinical Features

• Skin hydration: Clinical studies show lutein improves skin moisture by 38% after 12 weeks.
• Elasticity and wrinkles: Increases elasticity by 22% and reduces wrinkle depth by up to 33% in human trials.
• UV protection: Helps protect against sunburn and oxidative stress from UV rays.
• Skin tone: Promotes brightness and reduces oxidative damage that causes dullness.
• Antioxidant defense: Works with lycopene and beta-carotene to stabilize collagen and elastin.

Dosing
Typical dose: 6–20 mg/day. For skin, most clinical studies use 10–12 mg/day for 8–12 weeks. Best taken with meals containing fat.

Safety
Lutein is very safe, with no known toxicity. Extremely high intakes may cause a harmless yellowing of the skin (carotenodermia). Safe for long-term use and during pregnancy at dietary levels.

Mechanism of Action

• Blue-light filter: Absorbs high-energy light that causes oxidative stress.
• Antioxidant activity: Neutralizes ROS in skin and eye tissues.
• Collagen protection: Reduces breakdown from matrix metalloproteinases (MMPs).
• UV defense: Prevents lipid and DNA oxidation in skin cells.
• Synergistic action: Works with other carotenoids to enhance skin protection.