Medicinal Uses of Kelp, Laminaria genus

Scientific Name: Laminaria spp., including Laminaria digitata (oarweed)

Common Name: Kelp

Medicinal Uses of Kelp

Kelp has a wide range of medicinal uses, including thyroid support, metabolic balance, skin health, digestive support, and detoxification. Its rich mineral content, particularly iodine, along with antioxidants and polysaccharides, makes kelp a valuable herbal ally.

Thyroid Health and Metabolism Support

Kelp is most well known for its high iodine content, which is crucial for healthy thyroid function. The thyroid gland uses iodine to produce hormones that regulate metabolism, energy levels, and body temperature.

To support thyroid health:

• Add powdered kelp to soups or stews.
• Take kelp capsules if iodine intake is low.
• Use kelp flakes as a seasoning in place of salt. Regular consumption of kelp can help prevent iodine deficiency, which leads to hypothyroidism, weight gain, and fatigue. However, it’s important to avoid excessive intake, as too much iodine can disrupt thyroid balance.

Skin Healing and Anti-Ageing Properties

Kelp is rich in antioxidants, amino acids, and minerals that promote skin elasticity, reduce inflammation, and combat oxidative stress. Topical kelp preparations help soothe irritated skin, hydrate dry skin, and reduce signs of ageing.

To use kelp for skin care:

• Use powdered kelp in face masks to detoxify and nourish the skin.
• Add kelp extract to creams for anti-ageing benefits.
• Bathe in water infused with dried kelp to soothe eczema and psoriasis. The polysaccharides in kelp help retain moisture and promote collagen production, improving skin tone and elasticity.

Digestive Health

Kelp contains alginates and dietary fibre, which support gut health by promoting regular bowel movements and soothing inflammation in the digestive tract.

To use for digestion:

• Take kelp powder in smoothies to support healthy digestion.
• Use alginate-based supplements derived from kelp for heartburn and acid reflux relief.
• Kelp’s fibre also acts as a gentle prebiotic, supporting healthy gut flora.

Detoxification

Kelp binds to heavy metals and toxins, helping the body eliminate harmful substances through the digestive system. This makes it valuable for cleansing protocols and general detox support.

To use for detox:

• Drink kelp-infused broths or soups.
• Add powdered kelp to green detox smoothies.

Joint and Bone Health

Kelp is a rich source of calcium, magnesium, and trace minerals that support bone density and reduce inflammation in joints.

To use for joint health:

• Incorporate kelp powder or flakes into daily meals.
• Use fresh or rehydrated kelp or kelp-infused oils on sore joints. The presence of fucoidans (a type of polysaccharide) also gives kelp natural anti-inflammatory properties.

Cardiovascular Health

The potassium, magnesium, and antioxidants in kelp help support heart health by improving circulation, reducing blood pressure, and lowering cholesterol levels.

To use for heart health:

• Regularly consume kelp as part of a balanced diet.
• Drink kelp tea to help regulate blood pressure. Kelp can also reduce oxidative stress, which protects blood vessels and reduces the risk of heart disease.

Weight Management

Kelp contains fucoxanthin, a pigment that has been linked to promoting weight loss by boosting metabolism and reducing fat accumulation.

To use for weight management:

• Take kelp capsules or powder as part of a weight-loss regimen.
• Use kelp flakes in meals to gently boost metabolic function.

Respiratory Health

Kelp has traditionally been used to soothe the respiratory tract and break down mucus.

To use for respiratory support:

• Drink kelp-infused tea or broths to loosen mucus and ease coughs.
• Use powdered kelp mixed with honey for a soothing throat remedy.

Constituents

Kelp contains a variety of bioactive compounds, including:

• Iodine – Essential for thyroid function
• Fucoidan – Anti-inflammatory and immune-boosting properties
• Alginate – Supports digestion and detoxification
• Fucoxanthin – May aid in weight loss
• Vitamins A, C, E, and K – Antioxidants and skin health support
• Minerals – Calcium, magnesium, potassium, iron

Culinary Uses

Kelp is widely used in cooking, particularly in Asian cuisine:

• Kelp powder – Added to soups, stews, and smoothies
• Kelp flakes – Used as a seasoning
• Kombu (a type of kelp) – Added to broths and stocks
• Kelp noodles – A low-carb, mineral-rich pasta alternative

Foraging Notes

Habitat:

Kelp grows in cold, shallow waters along rocky coastlines. It is commonly found along the coasts of the North Atlantic, North Pacific, and around the British Isles.

Sustainability:

Forage kelp responsibly by only collecting loose pieces washed ashore or harvest small amounts from large, healthy beds. Use scissors to cut off the top third of the seaweed frond without uprooting the holdfast.

When to Harvest:

The best time to harvest kelp is at low tide, preferably during spring low tide around the full or new moon. This exposes the healthiest fronds in the lower intertidal zone, making them easy to gather without diving. Start just before the lowest point of the tide for safe, easy access to fresh, moist kelp.

Fresh kelp is abundant on many UK coastlines from late spring to autumn. Dried kelp is available year-round from online suppliers.

Key Identifiers:

• Long, flat, brown fronds with a smooth texture
• Holdfast (root-like structure) anchoring it to rocks
• Air bladders in some species to keep fronds afloat

Possible Lookalikes:

• Bladderwrack (Fucus vesiculosus) – Similar appearance but has smaller, bubble-like bladders
• Sugar kelp (Saccharina latissima) – Edible and medicinal with a sweet taste

Life History:

Kelp grows rapidly, sometimes up to 60 cm per day. It plays an essential ecological role by providing habitat for marine life and stabilising coastal ecosystems.

Classification:

Taxonomy:

Kelp belongs to the family Laminariaceae, order Laminariales, class Phaeophyceae.

Etymology:

The genus name Laminaria comes from the Latin word lamina, meaning “thin plate” or “layer,” referring to the broad, flat, sheet-like structure of the seaweed’s fronds.

The species name digitata comes from the Latin word digitus, meaning “finger.” This refers to the finger-like divisions or lobes of the fronds, giving the appearance of large, hand-like structures.

Fun Facts:

• Kelp forests are some of the most productive ecosystems on earth.
• Giant kelp (Macrocystis pyrifera) can grow at rates of up to 60 cm a day to lengths of up to 60 m, that’s as tall as a 20-storey skyscraper!
• Kelp was used in ancient times to produce potash and glass.
• In traditional Chinese medicine, kelp has been used for thousands of years to treat goitre and fluid retention.
• During times of famine, coastal communities relied on kelp as a nutritious food source.

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References

https://en.wikipedia.org/wiki/Kelp

https://www.healthline.com/nutrition/kelp-benefits