Background
Yellow dock (Rumex crispus) is a perennial herb traditionally valued for its cleansing and skin-supporting properties. Its root contains compounds that promote detoxification, support digestion, and reduce inflammation. For skin, yellow dock is often used to help with acne, eczema, and other conditions linked to toxin buildup or poor liver function.

Origin, Source, and Traditional/Historical Use
Native to Europe and Asia, yellow dock has spread worldwide as a wild herb. In traditional European and Native American medicine, its root was used as a blood purifier, liver tonic, and remedy for skin eruptions. Herbalists often recommended it for clearing acne and chronic skin conditions.

Key Active Compounds and Chemical Composition
Yellow dock root contains anthraquinones (emodin, chrysophanol), tannins, flavonoids, and minerals like iron. These compounds support liver detoxification, have mild laxative effects, and provide antioxidant protection that benefits skin health.

Bioavailability, Absorption, and Metabolism
The anthraquinones and tannins in yellow dock are absorbed in the intestine and metabolized in the liver. They promote bile flow and toxin elimination, which can indirectly reduce skin breakouts linked to poor detoxification.

Current Availability and Use
Yellow dock root is available as capsules, tinctures, teas, and standardized extracts. It is often included in herbal skin formulas for acne and eczema.

Clinical Features

• Acne support: Traditionally used to reduce acne flare-ups by improving liver clearance and lowering skin inflammation.
• Eczema and psoriasis: Herbal reports show improvements in redness and irritation after 8–12 weeks of use.
• Detoxification: Supports bile flow and toxin elimination, easing skin burden.
• Anti-inflammatory: Reduces cytokines that worsen acne and rashes.
• Iron support: Provides bioavailable iron, which helps improve skin tone in those with deficiency.

Dosing
Typical oral dose: 400–1000 mg/day of dried root in capsules, or 2–4 ml of tincture up to three times daily. Often combined with other herbs in skin-support formulas.

Safety
Generally safe when used at recommended doses. High doses may cause diarrhea, stomach upset, or electrolyte imbalance due to laxative anthraquinones. Not recommended during pregnancy or breastfeeding. People with kidney or liver disease should consult a healthcare provider before use.

Mechanism of Action

• Liver detox: Stimulates bile flow, improving toxin clearance.
• Anti-inflammatory: Anthraquinones and flavonoids reduce pro-inflammatory cytokines.
• Antioxidant activity: Protects skin cells from oxidative stress.
• Gut-skin axis: Promotes elimination and reduces toxin buildup that triggers acne.

Iron absorption: Provides natural iron that supports skin repair and glow

Background
Burdock (Arctium lappa) is a traditional herb valued for its detoxifying and skin-clearing effects. Its root contains compounds that support liver health, reduce inflammation, and promote circulation. For skin, burdock root has long been used to help with acne, eczema, and psoriasis.

Origin, Source, and Traditional/Historical Use
Native to Europe and Asia, burdock has been used in traditional Chinese medicine and European herbalism for centuries. It was regarded as a “blood purifier,” often recommended for treating boils, acne, and skin eruptions.

Key Active Compounds and Chemical Composition
Burdock root contains lignans (arctiin, arctigenin), inulin (a prebiotic fiber), polyphenols, and volatile oils. These compounds act as antioxidants, support detoxification, and promote gut and skin health.

Bioavailability, Absorption, and Metabolism
Polyphenols and lignans are absorbed in the small intestine, while inulin is fermented by gut bacteria to produce short-chain fatty acids that support the gut-skin axis. Active compounds are metabolized in the liver, enhancing detoxification pathways.

Current Availability and Use
Burdock root is available in capsules, teas, tinctures, and extracts. It is commonly included in skin, liver, and detox formulas.

Clinical Features

• Acne support: Burdock root reduces inflammation and improves skin clarity within 6–8 weeks in herbal studies.
• Eczema/psoriasis: Shown to ease itching and irritation in clinical use.
• Anti-inflammatory: Lowers cytokines linked to acne and skin redness.
• Antioxidant defense: Protects skin cells from oxidative stress.
• Gut-skin axis: Inulin supports healthy gut bacteria, which may indirectly improve skin.

Dosing
Common dose: 100–300 mg/day of root extract. Teas and tinctures are also used traditionally.

Safety
Generally safe at recommended doses. Rare allergic reactions may occur in people sensitive to daisies or ragweed. Safe in food amounts, but concentrated supplements should be avoided in pregnancy unless supervised.

Mechanism of Action

• Detoxification: Enhances liver clearance of toxins that affect skin.
• Prebiotic effect: Inulin supports beneficial gut flora.
• Collagen support: Lignans help reduce collagen breakdown.
• Anti-inflammatory: Reduces IL-6 and TNF-α, calming acne.
• Antioxidant action: Neutralizes ROS, preventing oxidative skin damage.

Background
Curcumin is the main bioactive compound in turmeric (Curcuma longa), a golden-yellow spice widely recognized for its anti-inflammatory and antioxidant properties. It is one of the most researched natural compounds for chronic inflammation, oxidative stress, and skin health. For acne-prone or inflamed skin, curcumin helps by reducing redness, controlling breakouts, and protecting against environmental stressors.

Origin, Source, and Traditional/Historical Use
Turmeric has been used in Ayurvedic and Chinese medicine for more than 4,000 years. Traditionally, it was applied as a paste for wounds, acne, and skin infections, and consumed as a tonic for digestion and blood purification. Modern extracts isolate curcumin, standardizing potency to provide consistent therapeutic effects.

Key Active Compounds and Chemical Composition
Curcumin (C21H20O6) belongs to the curcuminoid family, which also includes demethoxycurcumin and bisdemethoxycurcumin. These compounds act as antioxidants and regulators of inflammatory signaling pathways.

Bioavailability, Absorption, and Metabolism
Curcumin has naturally poor bioavailability due to rapid metabolism in the liver and intestines. However, absorption improves significantly when paired with piperine (from black pepper) or formulated with lipids. Once absorbed, curcumin circulates as active glucuronide and sulfate metabolites that retain biological activity.

Current Availability and Use
Curcumin supplements are sold worldwide in capsules, tablets, and standardized extracts. They are common in anti-inflammatory, joint, and skin formulas.

Clinical Features

• Acne reduction: Human studies show curcumin reduces acne lesion counts by up to 50% after 8–12 weeks.
• Anti-inflammatory: Inhibits inflammatory cytokines (TNF-α, IL-6) that worsen acne and eczema.
• Antioxidant defense: Neutralizes reactive oxygen species (ROS) that damage collagen and elastin.
• Wound healing: Speeds healing of skin injuries in both human and animal studies.
• UV protection: Reduces oxidative DNA damage from sunlight, helping prevent premature aging.

Dosing
Typical dose: 500–1000 mg/day standardized curcumin extract. For skin benefits, often combined with piperine or phospholipids for enhanced absorption.

Safety
Generally safe at recommended doses. High doses may cause mild digestive upset. Should be used with caution in people with gallstones or bile duct obstruction. Safe in pregnancy at dietary levels, though concentrated extracts should be avoided unless supervised.

Mechanism of Action

• NF-κB inhibition: Reduces activation of nuclear factor kappa B, lowering inflammatory signaling.
• COX-2 and LOX inhibition: Blocks enzymes involved in inflammation.
• Collagen protection: Prevents breakdown by inhibiting MMPs (matrix metalloproteinases).
• ROS scavenging: Neutralizes oxidative molecules before they damage skin cells.
• Immune regulation: Balances Th1/Th2 immune responses, reducing chronic inflammation.

Background
Quercetin is a plant flavonoid found in many fruits and vegetables. It is a powerful antioxidant and anti-inflammatory compound that helps protect skin, support the immune system, and reduce allergic reactions. For acne-prone or inflamed skin, quercetin helps by calming redness, balancing immune activity, and preserving collagen.

Origin, Source, and Traditional/Historical Use
Quercetin is naturally abundant in apples, onions, berries, grapes, and tea. Diets rich in quercetin-containing foods, such as the Mediterranean diet, have been associated with reduced inflammation and healthier skin. Herbal medicine traditions in Europe and Asia used quercetin-rich plants for wound healing, allergies, and skin rashes.

Key Active Compounds and Chemical Composition
Quercetin (C15H10O7) belongs to the flavonol subclass of flavonoids. In its dihydrate form, it has improved solubility and stability, which increases its bioavailability.

Bioavailability, Absorption, and Metabolism
Quercetin is absorbed in the small intestine and metabolized into glucuronide, sulfate, and methylated derivatives. Although bioavailability is moderate, its metabolites remain biologically active, contributing to antioxidant and anti-inflammatory effects.

Current Availability and Use
Quercetin supplements are available as capsules, tablets, and powders, often combined with bromelain to enhance absorption. It is included in skin, allergy, and immune health formulas.

Clinical Features

• Acne reduction: Decreases inflammatory cytokines and sebum oxidation, lowering acne severity within 8–12 weeks.
• Anti-inflammatory: Inhibits histamine release and reduces redness in eczema and dermatitis.
• Anti-aging: Protects collagen and elastin from degradation, reducing wrinkle depth.
• Wound healing: Stimulates fibroblasts and keratinocytes for faster repair.
• UV protection: Reduces DNA and lipid damage from UV radiation.

Dosing
Typical oral dose: 250–500 mg/day. Skin-health formulas often include 50–100 mg for daily antioxidant support.

Safety
Generally safe at recommended doses. High intakes may cause mild digestive upset or headache. Caution in pregnancy and with blood thinners.

Mechanism of Action

• NF-κB inhibition: Blocks activation of pro-inflammatory pathways.
• Histamine regulation: Stabilizes mast cells, reducing allergic responses.
• MMP inhibition: Protects collagen from breakdown enzymes.
• ROS scavenging: Neutralizes oxidative damage in skin cells.
• Immune modulation: Balances cytokine production (IL-6, TNF-α).

Background
Echinacea (Echinacea purpurea) is a flowering plant native to North America, well known for immune support and skin healing. It contains compounds that reduce inflammation, fight bacteria, and stimulate tissue repair. For skin, echinacea helps manage acne, eczema, and minor wounds.

Origin, Source, and Traditional/Historical Use
Native American tribes used echinacea for centuries to treat skin infections, wounds, and respiratory illness. European settlers adopted its use, and by the late 19th century, it was one of the most popular herbal remedies in the U.S. Modern extracts use the whole plant or root to maximize immune and skin benefits.

Key Active Compounds and Chemical Composition
Echinacea contains alkamides, caffeic acid derivatives (echinacoside, chlorogenic acid), polysaccharides, and flavonoids. These compounds work together to support immune function and reduce skin inflammation.

Bioavailability, Absorption, and Metabolism
Alkamides are well absorbed in the intestine and can cross the blood-brain barrier, influencing immune regulation. Polyphenols and polysaccharides are metabolized in the liver and contribute to systemic antioxidant activity.

Current Availability and Use
Echinacea is sold as capsules, tinctures, teas, and topical creams. It is widely used in immune-support and skin formulations, including acne and eczema blends.

Clinical Features

• Acne support: Reduces bacterial growth (including Propionibacterium acnes) and inflammation in skin.
• Wound healing: Human studies show echinacea extracts improve wound closure rates.
• Eczema relief: Lowers redness, itching, and swelling in atopic dermatitis.
• Anti-inflammatory: Reduces cytokines (IL-6, TNF-α) that drive acne and skin irritation.
• UV protection: Protects against oxidative damage from sun exposure.

Dosing
Typical oral dose: 300–500 mg/day standardized extract. Topical creams may use 1–2% echinacea extract for direct skin application.

Safety
Generally safe for short- to medium-term use. Rare allergic reactions in people sensitive to daisies. Avoid in autoimmune disorders unless under medical supervision.

Mechanism of Action

• Immune modulation: Activates macrophages and NK cells.
• Anti-inflammatory: Inhibits pro-inflammatory cytokines.
• Antimicrobial: Directly suppresses acne-causing bacteria.
• Collagen support: Enhances fibroblast activity and wound repair.
• Antioxidant defense: Protects against ROS-induced skin aging.

Background
Green tea (Camellia sinensis) is one of the most researched botanicals for health and longevity. Its leaves are rich in catechins, especially epigallocatechin gallate (EGCG), a strong antioxidant and anti-inflammatory compound. For skin, green tea protects against UV damage, reduces acne, and slows premature aging.

Origin, Source, and Traditional/Historical Use
Consumed for over 4,000 years in China and Japan, green tea has been prized for vitality, focus, and disease prevention. Traditional medicine used it for wound healing and skin soothing. Modern extracts standardize EGCG levels to ensure consistent potency.

Key Active Compounds and Chemical Composition
Green tea contains catechins (EGCG, epicatechin, epigallocatechin, epicatechin gallate), caffeine, and theanine. EGCG (C22H18O11) is the most bioactive, providing antioxidant and anti-carcinogenic activity.

Bioavailability, Absorption, and Metabolism
Catechins are absorbed in the small intestine but have limited bioavailability. EGCG absorption improves when taken on an empty stomach or with vitamin C. After metabolism in the liver, catechins circulate to skin tissues.

Current Availability and Use
Green tea extract is widely available as capsules, tablets, and powders, and is a common ingredient in topical creams and serums for acne and anti-aging.

Clinical Features

• Anti-aging: Human trials show improved skin elasticity and reduced wrinkles after 12 weeks.
• UV protection: Daily supplementation lowers sunburn risk and DNA damage.
• Acne reduction: EGCG regulates sebum and reduces P. acnes growth.
• Skin brightening: Inhibits melanin synthesis, reducing dark spots.
• Antioxidant support: Neutralizes free radicals, preserving collagen.

Dosing
Typical oral dose: 250–500 mg/day standardized extract (50% EGCG). Topical forms use 2–5% extract.

Safety
Generally safe at moderate doses. Very high intakes (>800 mg/day EGCG) may stress the liver. Contains small amounts of caffeine.

Mechanism of Action

• Antioxidant: Neutralizes ROS in skin cells.
• Collagen protection: Inhibits MMP enzymes that break down collagen.
• Sebum regulation: Lowers 5-α-reductase activity.
• Anti-inflammatory: Reduces NF-κB and cytokines like TNF-α.
• Melanin control: Blocks tyrosinase, reducing pigmentation.

Background
Grape seed extract is a rich source of oligomeric proanthocyanidins (OPCs), plant-based antioxidants stronger than vitamins C and E. For skin, it protects collagen, brightens pigmentation, and reduces wrinkles by fighting oxidative stress and UV damage.

Origin, Source, and Traditional/Historical Use
Grapes have been consumed for thousands of years in Mediterranean diets, and red wine was associated with vitality and longevity. In the late 20th century, researchers identified OPCs in grape seeds as potent antioxidants for skin and vascular health.

Key Active Compounds and Chemical Composition
The extract contains 95% OPCs, a class of flavonoids with exceptional free radical–scavenging capacity. They stabilize collagen, elastin, and capillaries.

Bioavailability, Absorption, and Metabolism
OPCs are absorbed in the small intestine, with plasma levels peaking within 2–3 hours. They circulate to skin tissues and are metabolized into active phenolic acids.

Current Availability and Use
Available in capsules, tablets, and powders since the 1980s, grape seed extract is common in skin, cardiovascular, and anti-aging formulas.

Clinical Features

• Anti-aging: Clinical studies show improved skin elasticity and reduced wrinkle depth in 12 weeks.
• UV protection: Protects against DNA damage from sunlight.
• Skin tone: Reduces melanin, improving hyperpigmentation.
• Antioxidant: OPCs are up to 50× more potent than vitamin E.
• Microcirculation: Strengthens capillaries, enhancing skin nutrient delivery.

Dosing
Typical oral dose: 100–300 mg/day standardized extract (95% OPCs).

Safety
Generally safe. Mild nausea or headache in rare cases. May increase bleeding risk with anticoagulants.

Mechanism of Action

• Antioxidant: Neutralizes ROS and regenerates vitamins C and E.
• Collagen stabilization: Cross-links collagen fibers for durability.
• Anti-inflammatory: Reduces IL-6 and TNF-α.
• Tyrosinase inhibition: Lowers melanin production.
• Capillary strengthening: Enhances nitric oxide, improving circulation.

Background
Bromelain is a natural enzyme complex extracted from pineapple stems and juice. It is best known for reducing inflammation, aiding digestion, and promoting wound healing. For skin, bromelain helps reduce acne swelling, improve healing, and calm irritated tissues.

Origin, Source, and Traditional/Historical Use
Pineapple has been used in South America for centuries as a digestive aid and wound remedy. In the 1950s, bromelain was isolated and commercialized as a therapeutic enzyme.

Key Active Compounds and Chemical Composition
Bromelain is a mixture of proteolytic enzymes, peroxidases, and acid phosphatases. These enzymes break down proteins, reduce inflammation, and aid tissue repair.

Bioavailability, Absorption, and Metabolism
Bromelain is absorbed in the small intestine and detectable in the bloodstream within hours, retaining proteolytic activity.

Current Availability and Use
It is widely available as capsules, powders, and enzyme blends. Used in skin, joint, and digestive health formulas.

Clinical Features

• Anti-inflammatory: Reduces swelling and redness in acne and dermatitis.
• Wound healing: Improves tissue repair and reduces scarring.
• Antimicrobial: Inhibits bacterial growth linked to acne.
• Exfoliation: Used topically to gently remove dead skin.
• Synergy: Enhances absorption of flavonoids like quercetin.

Dosing
Typical oral dose: 200–800 mg/day, standardized to proteolytic activity (measured in GDU or MCU).

Safety
Generally safe; mild nausea or diarrhea may occur. Avoid in pineapple allergy. Caution with blood thinners due to increased bleeding risk.

Mechanism of Action

• Proteolysis: Breaks down proteins that fuel inflammation.
• Cytokine regulation: Lowers IL-1β, IL-6, and TNF-α.
• Fibrinolysis: Reduces fibrin deposition in inflamed skin.
• Immune support: Modulates T-cell responses.
• Synergistic activity: Enhances uptake of antioxidants.

Background
Soy isoflavones are plant-derived compounds classified as phytoestrogens, meaning they have mild estrogen-like activity in the body. For skin, they help improve elasticity, reduce wrinkles, and support collagen by interacting with estrogen receptors in skin cells.

Origin, Source, and Traditional/Historical Use
Soybeans (Glycine max) have been a staple in Asian diets for thousands of years. In traditional Chinese medicine, soy foods were associated with vitality, skin glow, and hormonal balance. Modern supplements extract and concentrate isoflavones, such as genistein and daidzein.

Key Active Compounds and Composition
Isoflavones include genistein, daidzein, and glycitein. These compounds are structurally similar to estrogen and bind to estrogen receptor beta in skin cells, stimulating collagen production and antioxidant activity.

Bioavailability, Absorption, and Metabolism
Isoflavones are absorbed in the small intestine and metabolized by gut bacteria into active metabolites like equol. They are transported in the blood to skin and other tissues.

Current Availability and Use
Soy isoflavone supplements are sold in capsules, tablets, and powders. They are common in anti-aging, bone, and menopausal support formulas.

Clinical Features

• Anti-aging: Human studies show improved skin thickness, elasticity, and reduced wrinkles after 12 weeks.
• Collagen support: Stimulates fibroblasts to increase collagen and hyaluronic acid.
• Skin hydration: Improves moisture retention.
• Pigmentation control: Helps reduce melasma and dark spots.
• Antioxidant defense: Neutralizes oxidative damage to skin cells.

Dosing
Typical dose: 20–100 mg/day standardized extract (40% isoflavones).

Safety
Generally safe at recommended doses. Mild stomach upset may occur. Caution in individuals with estrogen-sensitive cancers.

Mechanism of Action

• Estrogen receptor binding: Activates ER-β in skin, boosting collagen.
• Antioxidant: Neutralizes ROS.
• MMP inhibition: Prevents collagen breakdown.
• Melanin regulation: Lowers tyrosinase activity, reducing hyperpigmentation.
• Fibroblast stimulation: Enhances skin repair and hydration.

Background
Chastetree berry, also known as Vitex, is a Mediterranean herb traditionally used to support hormonal balance. For skin, it is especially helpful in acne linked to menstrual cycles or hormone fluctuations.

Origin, Source, and Traditional/Historical Use
Vitex has been used in Greek, Roman, and medieval European medicine for female reproductive health. Monks in the Middle Ages reportedly used it to reduce sexual desire, giving it the name “chaste tree.”

Key Active Compounds and Composition
Vitex contains iridoid glycosides (agnuside), flavonoids, and diterpenes that influence the pituitary gland, balancing levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin.

Bioavailability, Absorption, and Metabolism
Vitex compounds are absorbed in the intestine and act indirectly through pituitary hormone regulation, influencing estrogen and progesterone balance.

Current Availability and Use
Vitex is widely available in capsules, tinctures, and tablets. It is included in women’s health supplements, especially for PMS, acne, and cycle regulation.

Clinical Features

• Acne relief: Improves hormone-related acne, particularly around menstruation.
• Hormone balance: Regulates estrogen-progesterone ratios.
• PMS support: Reduces breast tenderness, bloating, and irritability.
• Skin clarity: By lowering prolactin, Vitex may reduce breakouts.
• Anti-inflammatory: Provides mild calming effects for inflamed skin.

Dosing
Typical oral dose: 20–40 mg/day of standardized extract.

Safety
Generally safe. Mild nausea or dizziness possible. Not recommended during pregnancy.

Mechanism of Action

• Dopamine agonist: Lowers prolactin levels.
• Hormone modulation: Balances estrogen and progesterone.
• Sebum regulation: Reduces hormone-driven oil production.
• Anti-inflammatory: Lowers cytokine activity in acne-prone skin.

Background
Milk thistle (Silybum marianum) is a Mediterranean herb known for liver protection and detoxification. Its extract, rich in silymarin, supports skin health by improving toxin clearance, reducing inflammation, and protecting collagen.

Origin, Source, and Traditional/Historical Use
Used for over 2,000 years in Greek and Roman medicine, milk thistle was a remedy for liver and skin conditions. Modern extracts are standardized for silymarin (70–80%).

Key Active Compounds and Composition
Silymarin is a mixture of flavonolignans, including silybin, silydianin, and silychristin. These act as antioxidants, membrane stabilizers, and anti-inflammatories.

Bioavailability, Absorption, and Metabolism
Silymarin has moderate absorption, but bioavailability improves with phospholipid complexes. It is metabolized in the liver and supports detoxification pathways important for skin clarity.

Current Availability and Use
Milk thistle extract is available worldwide in capsules, tablets, and tinctures. It is included in liver and skin support supplements.

Clinical Features

• Acne and skin clarity: Improves detoxification, reducing acne flare-ups.
• UV protection: Shields skin from oxidative DNA damage.
• Anti-aging: Preserves collagen and elastin by blocking breakdown enzymes.
• Wound healing: Enhances fibroblast activity for repair.
• Anti-inflammatory: Lowers cytokines that worsen skin redness.

Dosing
Typical oral dose: 200–400 mg/day of standardized extract (70–80% silymarin).

Safety
Generally safe; mild stomach upset possible. Caution for people allergic to daisies. Safe in pregnancy at food levels but not recommended in concentrated extracts.

Mechanism of Action

• Antioxidant: Boosts glutathione and scavenges ROS.
• Liver detox: Improves toxin clearance.
• Collagen protection: Inhibits matrix metalloproteinases.
• Anti-inflammatory: Lowers IL-6 and TNF-α.
• Cell repair: Stabilizes membranes and promotes regeneration.

Background
Bifidobacterium lactis is a probiotic bacterium naturally found in the human gut and in fermented foods like yogurt. It supports digestive health, immune balance, and skin health through the gut-skin axis. For acne, it helps by reducing inflammation and improving gut barrier function.

Origin, Source, and Traditional/Historical Use
Bifidobacteria were first identified in infants’ intestines in the late 19th century. Foods like kefir and yogurt have long been consumed for gut health, indirectly supplying these strains. Today, B. lactis is widely used in probiotic supplements.

Key Active Compounds and Composition
B. lactis produces lactic acid, short-chain fatty acids (SCFAs), and antimicrobial peptides that support gut flora balance and reduce skin inflammation.

Bioavailability, Absorption, and Metabolism
When taken orally, B. lactis survives stomach acid and colonizes the colon. It interacts with intestinal immune cells, modulating systemic inflammation that influences skin.

Current Availability and Use
Found in probiotic capsules, powders, and dairy products. Included in skin-targeted probiotics for acne and eczema.

Clinical Features

• Improves gut barrier, reducing systemic inflammation.
• Reduces acne severity by lowering inflammatory cytokines.
• Eczema support: lowers itching and flare-ups in children and adults.
• Immune balance: decreases excessive immune reactions.
• Enhances nutrient absorption important for skin health.

Dosing
Common dose: 1–10 billion CFU/day. Often combined with other probiotic strains.

Safety
Generally recognized as safe (GRAS). Suitable for children, adults, and pregnant women. Rare mild digestive symptoms may occur.

Mechanism of Action

• Produces SCFAs (butyrate) that reduce inflammation.
• Enhances gut barrier function, lowering endotoxin leakage.
• Regulates IL-10 (anti-inflammatory cytokine).
• Reduces oxidative stress.
• Balances gut microbiome diversity.

Background
Bifidobacterium longum is a probiotic species naturally present in the human gut. It supports digestion, reduces oxidative stress, and helps regulate the immune system. In skin health, it improves barrier function, reduces acne inflammation, and calms sensitive skin.

Origin, Source, and Traditional/Historical Use
First isolated from infant intestines, B. longum is one of the earliest colonizers of the human gut. Fermented foods like miso and yogurt contain natural bifidobacteria.

Key Active Compounds and Composition
Produces SCFAs, vitamins (B-group), and antioxidant enzymes. It lowers gut and systemic inflammation, influencing skin outcomes.

Bioavailability, Absorption, and Metabolism
Survives gastric acid and colonizes the colon. Communicates with gut-associated lymphoid tissue (GALT), regulating immune activity.

Current Availability and Use
Widely used in probiotic capsules and fermented dairy products. Included in skin and anti-inflammatory blends.

Clinical Features

• Improves skin barrier function, reducing dryness and redness.
• Reduces acne flare-ups by modulating immune responses.
• Improves eczema symptoms in both children and adults.
• Lowers oxidative stress in vivo.
• Supports gut-brain-skin axis, reducing stress-related skin issues.

Dosing
Typical dose: 1–10 billion CFU/day.

Safety
Generally safe. May cause mild gas or bloating initially. Safe for children and pregnant women.

Mechanism of Action

• Enhances gut barrier, preventing toxin leakage.
• Reduces inflammatory cytokines (IL-6, TNF-α).
• Promotes antioxidant activity (superoxide dismutase).
• Produces vitamins that support skin repair.
• Modulates Th1/Th2 immune balance.

Background
Lactobacillus acidophilus is one of the most well-studied probiotics, known for promoting gut health, improving immunity, and supporting skin clarity. For acne, it helps by balancing gut bacteria, reducing inflammation, and limiting growth of harmful microbes.

Origin, Source, and Traditional/Historical Use
Naturally found in the human gut and fermented foods like yogurt, kefir, and sauerkraut. Historically, cultures consuming these foods reported improved digestion and skin clarity.

Key Active Compounds and Composition
Produces lactic acid, hydrogen peroxide, bacteriocins, and SCFAs, which inhibit harmful bacteria and regulate pH.

Bioavailability, Absorption, and Metabolism
Survives passage through the stomach and colonizes the small intestine and colon. It interacts with immune cells in the gut to lower systemic inflammation.

Current Availability and Use
Common in probiotic capsules, yogurts, and dairy-based supplements. Often included in blends for acne, eczema, and immune health.

Clinical Features

• Reduces acne lesions by lowering Propionibacterium acnes activity.
• Improves eczema and dermatitis symptoms in clinical studies.
• Boosts immune defense against skin infections.
• Supports gut-skin axis by lowering inflammation.
• Enhances nutrient absorption (zinc, B vitamins) for skin health.

Dosing
Typical oral dose: 1–10 billion CFU/day.

Safety
Recognized as safe. Occasional mild digestive upset may occur. Safe for children and during pregnancy.

Mechanism of Action

• Produces lactic acid, lowering intestinal pH to suppress pathogens.
• Enhances IL-10 (anti-inflammatory cytokine).
• Stimulates regulatory T-cells, calming overactive immune responses.
• Protects skin collagen by reducing systemic inflammation.
• Competes with harmful microbes in gut and on skin.

Background
Lactobacillus paracasei is a probiotic strain known for strengthening the skin barrier, modulating the immune system, and reducing inflammatory responses that can worsen acne and eczema. It is often studied for its ability to improve both gut and skin health.

Origin, Source, and Traditional/Historical Use
Naturally present in the human intestinal tract, oral cavity, and fermented dairy products such as cheese and kefir. Historically, populations consuming high levels of fermented foods containing L. paracasei showed better digestive tolerance and healthier skin.

Key Active Compounds and Composition
Produces lactic acid, bacteriocins, and exopolysaccharides that inhibit harmful pathogens, reduce oxidative stress, and support skin hydration and balance.

Bioavailability, Absorption, and Metabolism
Demonstrates good survivability through stomach acid and bile salts. Colonizes both the small intestine and colon, where it interacts with immune cells and gut epithelial cells to improve systemic and skin-specific outcomes.

Current Availability and Use
Widely available in probiotic blends, capsules, and functional foods. Frequently included in supplements targeting immunity, allergies, digestion, and skin clarity.

Clinical Features

• Reduces skin sensitivity and redness by stabilizing the skin barrier.
• Improves symptoms of atopic dermatitis and allergic reactions in studies.
• May help reduce acne flare-ups by lowering systemic inflammation.
• Strengthens gut-skin axis by improving gut microbial balance.
• Enhances hydration and elasticity of skin in some clinical trials.

Dosing
Typical oral dose: 1–10 billion CFU/day.

Safety
Recognized as safe. Occasional mild gastrointestinal symptoms (gas, bloating) may occur. Safe for children, adults, and during pregnancy.

Mechanism of Action

• Produces lactic acid to lower gut pH and suppress harmful bacteria.
• Stimulates regulatory immune responses, lowering inflammation.
• Enhances tight junction integrity in the gut barrier, reducing systemic toxin exposure.
• Protects skin barrier function by reducing oxidative stress and inflammatory mediators.
• Promotes balance of skin microbiota indirectly through gut-skin communication.

Background
Lactobacillus plantarum is one of the most versatile probiotic species, widely studied for its role in balancing gut microbiota, reducing oxidative stress, and improving skin hydration. It has strong antioxidant activity and helps regulate inflammation, making it valuable for acne, eczema, and premature aging of skin.

Origin, Source, and Traditional/Historical Use
Naturally found in fermented foods such as sauerkraut, kimchi, pickles, and sourdough. Historically, societies consuming plant-based fermented foods rich in L. plantarum reported improved digestive and immune function, along with skin resilience.

Key Active Compounds and Composition
Produces lactic acid, hydrogen peroxide, bacteriocins, and bioactive peptides with antimicrobial and antioxidant effects. Its exopolysaccharides enhance gut barrier integrity and reduce skin inflammation.

Bioavailability, Absorption, and Metabolism
Highly adaptable, surviving both gastric acid and bile salts. Efficiently colonizes the gut, where it interacts with epithelial cells and immune cells to lower inflammation and oxidative damage.

Current Availability and Use
Available in capsules, powders, and fermented food products. Often included in probiotic blends targeting gut health, immune support, and skin clarity.

Clinical Features

• Reduces acne lesion severity by lowering inflammatory cytokines.
• Improves skin hydration and elasticity in human trials.
• Enhances antioxidant defenses, protecting collagen and skin lipids.
• Shown to alleviate symptoms of atopic dermatitis and irritable bowel syndrome.
• Helps regulate lipid metabolism, which may reduce sebum overproduction.

Dosing
Typical oral dose: 1–20 billion CFU/day.

Safety
Generally recognized as safe. Minimal side effects (bloating, mild gas) may occur at high doses. Safe for long-term use.

Mechanism of Action

• Produces lactic acid to suppress acne-causing bacteria.
• Reduces pro-inflammatory cytokines like IL-6 and TNF-α.
• Increases antioxidant enzymes such as superoxide dismutase (SOD).
• Enhances gut barrier integrity, reducing systemic inflammation.
• Balances lipid metabolism and skin microbiota to reduce acne severity.

Background
Lactobacillus rhamnosus is a clinically well-documented probiotic, particularly known for its immune-modulating properties and benefits for skin health. It helps reduce acne flare-ups, supports eczema management, and promotes a smoother complexion through its gut-skin axis influence.

Origin, Source, and Traditional/Historical Use
Naturally inhabits the human gut and vaginal microbiota. Widely found in fermented dairy products such as yogurt and kefir. Traditionally used in probiotic-rich diets to improve digestion and overall resilience against infections.

Key Active Compounds and Composition
Produces lactic acid, short-chain fatty acids, and bioactive proteins that suppress pathogenic bacteria and calm immune overactivation. Known for secreting bacteriocins that directly inhibit harmful microbes.

Bioavailability, Absorption, and Metabolism
Proven survivability through gastric acidity and bile salts. Can adhere to intestinal epithelial cells and modulate immune signaling, influencing both gut and skin health.

Current Availability and Use
One of the most common probiotics in commercial formulations. Present in supplements, yogurts, dairy drinks, and blends for skin, digestive, and immune health.

Clinical Features

• Reduces acne severity by modulating systemic inflammation.
• Improves eczema outcomes, especially in children and pregnant women.
• Shown to reduce allergic skin reactions and skin barrier dysfunction.
• Supports gut balance, indirectly improving skin clarity.
• May help reduce stress-related skin flare-ups via gut-brain-skin axis.

Dosing
Typical oral dose: 1–10 billion CFU/day; higher doses (up to 20 billion) studied for eczema.

Safety
Widely regarded as safe. Rarely causes mild digestive upset. Suitable for children, adults, and pregnant women.

Mechanism of Action

• Produces lactic acid to suppress acne-causing bacteria and pathogens.
• Increases anti-inflammatory cytokines (IL-10) and decreases pro-inflammatory markers.
• Supports regulatory T-cell activation for immune balance.
• Strengthens intestinal barrier, reducing systemic toxin exposure that worsens skin inflammation.
• Modulates gut-brain-skin axis, improving stress-related skin outcomes.

Background
Vitamin A is an essential nutrient that supports healthy skin, vision, and immune function. It plays a key role in skin renewal, reducing acne, and protecting against dryness and early aging. Retinyl acetate is a preformed form of vitamin A, while beta carotene is a plant-based form that the body can turn into vitamin A when needed.

Origin, Source, and Traditional/Historical Use
Retinyl acetate is derived from animal sources and used in supplements for reliable absorption. Beta carotene comes from colorful fruits and vegetables like carrots, sweet potatoes, and spinach. For centuries, people noticed that diets rich in these foods helped improve skin glow and prevent night blindness.

Key Active Compounds and Composition

• Retinyl acetate – a stable form of vitamin A, directly used by the body for skin and vision.
• Beta carotene – a natural antioxidant and vitamin A precursor (provitamin A).

Bioavailability, Absorption, and Metabolism
Retinyl acetate is absorbed quickly and stored in the liver for future use. Beta carotene is absorbed in the intestine, then converted to vitamin A depending on the body’s needs—this prevents excess buildup.

Current Availability and Use
Widely available in multivitamins, skin supplements, and fortified foods. Commonly used to support clear skin, eye health, and immune defense.

Clinical Features

• Helps reduce acne by regulating oil production in the skin.
• Speeds up skin cell turnover, supporting healing and renewal.
• Prevents dryness, rough patches, and clogged pores.
• Beta carotene provides antioxidant protection against free radicals.
• Supports night vision and protects the eyes from oxidative stress.

Dosing

• Adults: 700–900 mcg RAE (Retinol Activity Equivalents) daily.
• Supplements often provide 900–1500 mcg RAE/day in safe amounts.

Safety

• Beta carotene is very safe, as the body only converts what it needs.
• Retinyl acetate should not be taken in very high doses for long periods, as too much vitamin A can cause side effects (headache, nausea, liver strain).
• Safe for most people at recommended levels; always check prenatal use.

Mechanism of Action

• Regulates skin cell growth and reduces buildup that causes clogged pores.
• Controls oil (sebum) production in the skin, lowering acne risk.
• Works as an antioxidant, reducing damage from free radicals.
• Supports collagen production and slows early skin aging.
• Strengthens immune defenses, helping skin fight infections.

Background
Niacin, also called vitamin B3, is an important nutrient for energy, skin, and brain health. The form called niacinamide is especially gentle and skin-friendly. It helps reduce acne, redness, and uneven tone while supporting clear, healthy skin.

Origin, Source, and Traditional/Historical Use
Niacin was first discovered in the early 1900s as the vitamin that prevents pellagra, a disease causing skin rashes and weakness. Today, niacinamide is found in foods like chicken, fish, peanuts, and whole grains. For decades, doctors and scientists have studied its role in improving skin barrier and reducing inflammation.

Key Active Compounds and Composition
Niacinamide is the active form of niacin that the body uses in over 400 enzyme reactions. It helps create NAD+ (nicotinamide adenine dinucleotide), a key molecule for energy, skin repair, and cell defense.

Bioavailability, Absorption, and Metabolism
Easily absorbed in the small intestine and quickly converted into NAD+ in cells. Unlike niacin (nicotinic acid), niacinamide does not cause flushing or tingling.

Current Availability and Use
Found in multivitamins, B-complex supplements, skin supplements, and topical serums. Often included in acne and skin-brightening formulas.

Clinical Features

• Reduces acne and oiliness by calming overactive sebaceous glands.
• Improves skin hydration and barrier function, lowering dryness and redness.
• Helps fade dark spots and uneven tone (hyperpigmentation).
• Lowers inflammation that can worsen acne and rosacea.
• Supports energy metabolism and overall skin resilience.

Dosing

• Usual supplement dose: 16 mg/day for men, 14 mg/day for women.
• Skin and acne supplements often contain 20–500 mg/day in safe ranges.

Safety

• Generally very safe at standard doses.
• High doses (above 1,000 mg/day) may cause mild nausea or liver strain if used long-term.
• Does not cause flushing like regular niacin.

Mechanism of Action

• Builds NAD+, fueling cell energy and repair.
• Reduces inflammation and oxidative stress linked to acne and aging.
• Strengthens skin barrier proteins like ceramides.
• Regulates oil production to lower acne breakouts.
• Improves DNA repair in skin cells exposed to UV damage.

Background
Zinc is an essential mineral that plays a major role in skin healing, immune defense, and reducing acne. The form zinc ascorbate combines zinc with vitamin C (ascorbic acid), which improves absorption and adds antioxidant support. This makes it especially useful for clearer skin and faster repair of breakouts.

Origin, Source, and Traditional/Historical Use
Zinc is naturally found in foods like pumpkin seeds, meat, beans, nuts, and whole grains. For centuries, zinc-rich foods have been linked to faster wound healing and stronger immunity. Zinc deficiency was first linked to skin problems and poor growth in the 1960s, making it a key nutrient in both traditional and modern health practices.

Key Active Compounds and Composition

• Zinc – regulates oil glands, supports immune defenses, and repairs skin tissue.
• Ascorbate (Vitamin C) – helps protect skin cells from oxidative stress and supports collagen production.

Bioavailability, Absorption, and Metabolism
Zinc ascorbate is highly bioavailable—meaning the body absorbs it well. The vitamin C component helps zinc dissolve and be transported more effectively in the gut. Once absorbed, zinc is stored in muscles, bones, and skin, where it helps enzymes work properly.

Current Availability and Use
Available in dietary supplements, multivitamins, and skin-focused formulations. Commonly used for acne management, immune support, and faster wound recovery.

Clinical Features

• Reduces acne breakouts by regulating oil (sebum) production.
• Supports healing of pimples, scars, and skin injuries.
• Strengthens immune defenses against acne-causing bacteria.
• Works with vitamin C to support collagen for smoother skin.
• Reduces redness and inflammation in acne-prone skin.

Dosing

• Recommended daily intake: 8 mg/day for women, 11 mg/day for men.
• Acne and skin supplements typically provide 15–30 mg/day in safe amounts.

Safety

• Generally safe at recommended doses.
• Very high intakes (over 40 mg/day long-term) may cause nausea, stomach upset, or lower copper levels.
• Short-term use of moderate supplements for acne is well tolerated.

Mechanism of Action

• Regulates keratin and oil gland activity, lowering pore blockages.
• Reduces inflammatory cytokines linked to acne.
• Blocks growth of acne-causing bacteria (Cutibacterium acnes).
• Works with vitamin C to boost antioxidant protection in skin cells.
• Speeds up collagen formation and tissue repair.

Background
Chromium is a trace mineral that helps the body manage blood sugar and insulin. The form chromium polynicotinate is a highly absorbable type made by combining chromium with niacin (vitamin B3). Stable blood sugar levels are linked to clearer skin, because high spikes in insulin can trigger more oil production and acne flare-ups.

Origin, Source, and Traditional/Historical Use
Chromium is naturally found in small amounts in foods like broccoli, whole grains, nuts, and meats. It was identified in the 1950s as an essential nutrient for glucose (sugar) metabolism. Historically, chromium-rich diets have been linked to steadier energy and better weight control.

Key Active Compounds and Composition

• Chromium – helps insulin work better, improving how cells use sugar for energy.
• Niacin (as part of polynicotinate) – improves absorption and provides added support for circulation and skin health.

Bioavailability, Absorption, and Metabolism
Chromium polynicotinate is one of the most bioavailable forms of chromium. The niacin “carrier” helps transport chromium into cells more effectively compared to chromium chloride or other basic salts. Once absorbed, chromium is stored in the liver, kidneys, and bones.

Current Availability and Use
Available in supplements for blood sugar control, energy, and metabolism. Often included in formulas for weight management, skin clarity, and overall wellness.

Clinical Features

• Helps regulate blood sugar and insulin levels.
• Reduces insulin spikes that can worsen acne.
• May support weight management by lowering cravings and balancing appetite.
• Supports healthier metabolism of carbs, fats, and proteins.
• Promotes steady energy levels, which can reduce stress-related breakouts.

Dosing

• Daily needs: 25–35 mcg for adults.
• Supplements often provide 100–200 mcg/day of chromium polynicotinate for metabolic and skin support.

Safety

• Safe at recommended levels.
• Very high doses (above 1,000 mcg/day) may cause stomach upset or interact with certain medications for blood sugar.
• Should be used cautiously by people with diabetes under medical guidance.

Mechanism of Action

• Enhances insulin sensitivity, improving sugar uptake into cells.
• Prevents excess insulin, which reduces oil (sebum) overproduction linked to acne.
• Works with niacin to support blood flow and nutrient delivery to skin.
• May reduce inflammation and oxidative stress related to poor glucose control.