Sea plants come from many rocky coastal areas worldwide. The intensity of light on the ocean depths affects color spectrums and the ability of sea plants to undergo photosynthesis. They have varying forms of growth—the thallus (or body) consists of flat or leaf-like structures known as blades that originate from elongated stem-like structures, the stipes. A root-like structure, the holdfast, anchors the kelp to the substrate of the ocean.

Sea Plants Contain:

  • Minerals: (10-35%) including many trace, some Ca & Mg (about 1% ea)
  • Amino Acids: (6-20%) full protein spectrum
  • Vitamins: high in B Vitamins, contains Vitamin K, some Vitamin C, carotenoids, antioxidants, fats (0.5 – 3%)
  • Enzymes: many types, help reduce inflammation and assist the body with digesting fats
  • Complex Carbohydrates: (40-50%) – are slowly released, balance blood sugar
  • Digestible Fiber (8-45%) – cleans colon. It is soothing and nutritious.
  • Plant iodines: highest in brown algae – helps with gland disorders
  • Sulfated polysaccharides: Long-chain amino sugars bind to heavy metals

Sea Plant Benefits:

  • Chelator of heavy metals: detoxifies the body, lightens the burden on the liver and kidneys
  • Restorative, nutritious, moisturizing, cooling
  • Soothes a cough, relieves swelling, is anti-spasmodic, calming, nourishing
  • Anti-inflammatory: Studies show an improvement in joint health and mobility
  • Help “feed” nerves, energy, and metabolism; provides balance via natural minerals; supports adrenal glands
  • Help balance blood sugar and assists with the slow release of carbohydrates
  • Skincare: have nourishing, moisturizing properties—literally food for skin
  • Used as a thickener in gels and ice cream. Can be used to slightly thicken and stabilize foods
  • Provide nourishment to plants; benefit gardens; can be used as mulch or a natural fertilizer

Types of Sea Plants

Brown Algae (Phaeophyta)

There are 15,000 –20,000 species of brown algae. Brown algae are all loaded with B vitamins, carotenoids, and contain the most iodine of all sea plants. They also contain fucoxanthin, a powerful antioxidant and pigment responsible for the plants’ olive-brown color. Some species of brown algae have gas-filled bladders (pneumatocysts).

Kelp (Ascophyllum nodosum)

  • Brown to olive-colored sea plants that make up the order Laminariales. There are about 30 different genera (taxonomic rank above species) of brown to olive-colored sea plants.
  • They grow in northern regions (northern Europe, Canada, Norway, and Iceland).
  • They provide habitat and are food for a wide range of fish and invertebrates.
  • A nutritionally rich food source containing Vitamins A, B, C, E, and K, dietary fiber, Omega-3 fatty acids, amino acids, magnesium, iron, iodine, and prebiotics.
  • Contains naturally occurring mannitol, a sugar alcohol with a sweet and pleasant taste.
  • Rich source of glutamic acid, which gives sea plants a unique flavor and taste.
  • Promote gut and bone health, weight management, and are a natural anti-inflammatory.
  • Icelandic kelp iodine content: 8,000 ppm
  • Norwegian kelp iodine content: 4,000 ppm
  • Atlantic kelp iodine content: 1,500–2,000 ppm
  • Pacific Kelp iodine content: 500–1,200 ppm

Rockweed (Cystoseira geminata)

  • Commonly found along the northern Atlantic coast.
  • The fronds of Rockweed form a protective canopy for smaller organisms.
  • Rockweed uptakes carbon dioxide from the atmosphere to use in the photosynthesis process to produce food. They release oxygen into the atmosphere.
  • They can be added directly to gardens as a fertilizer or mulch.

Giant Bullwhip Kelp (Macrocystis pyrifera)

  • Nereocystis (Leutkeana Limitada) and Feathered Boa (Egregia Menzies) are similar sea plants.
  • They inhabit rocky shores in temperate and subpolar latitudes.
  • They contain large blades and a flexible stipe (stem) of 30–60 feet. They can grow up to 150 feet.
  • They form massive kelp forests and are a habitat for many species.
  • They are harvested as a food source and for their algin, an emulsifying and bonding agent used in many foods and cosmetics.
  • Contains antioxidants, vitamins, and minerals, including calcium and iodine. Their nutrients can help with cardiovascular health, diabetes management, bone and digestive health, and an improved immune system.

Kombu (Saccharina japonica or Laminaria japonica)

  • In the Kelp family; its genus is Laminariaceae.
  • Native to the northern Atlantic and Pacific oceans.
  • Contains Vitamins A, B, C, and E, iron, calcium, fiber, iodine, and trace minerals.
  • They are also high in Vitamin D, which helps the body absorb calcium.
  • It is a natural flavor enhancer and is widely eaten in East Asia.

Alaria (Alaria esculenta)

  • Found in the far north coasts of the Atlantic Ocean.
  • Has long been a traditional food in European and Native American coastal cultures.
  • Rich in minerals including calcium, magnesium, potassium, iron, and iodine.
  • Contains vitamins, most notably Vitamins A, B2, B3, and C.
  • Contains dietary fiber, polyphenols, and the most protein of any brown sea vegetable, about 12% when dried.
  • Can be added to soups, cooked vegetables, and salads.

Sea Palms (Postelsia palmaeformis)

  • An annual species that is one of the few that can survive out of water.
  • Found along the western coasts of North America on rocky shores.
  • Resembles a small palm tree. When they mature, they turn from green to golden brown.
  • It is illegal to commercially harvest sea palms in Oregon, Washington, and British Columbia. In California, sea palms are protected.

Bladderwrack (Fucus vesiculosus)

  • Found on the coasts of the North Sea, the Atlantic and Pacific Oceans, and the west coast of the Baltic Sea,
  • Rich in nutrients including the B-complex vitamins, Vitamins A, C, and E, calcium, iodine, iron, magnesium, potassium, sodium, sulfur, silicon, and fiber; it has high anti-inflammatory benefits.
  • Used in skin care products to help soothe skin irritations such as burns and bites. Also nourishes, hydrates, and softens skin and improves skin elasticity.
  • Preliminary studies show that bladderwrack may help alleviate constipation and speed up wound healing.
  • Add to soups or cooked vegetables; the tips are very tasty.

Arame (Eisenia bicyclis)

  • Grow off the shores of Ise Shima, Japan.
  • They are the sweetest of all sea vegetables and have a pleasant texture and appearance.
  • Arame is rich in antioxidants and contains fiber, calcium, magnesium, iodine, iron, and potassium.

Red Algae (Rhodophyta)

Red algae are marine plants that are good sources of many vitamins and minerals, including those that support a healthy immune system. They are powerful antioxidants and have anti-inflammatory and antimicrobial properties. There are about 6,000 red algae species.

Lithothamniom (Calcereum)

  • Found in northern waters from Ireland to Iceland
  • Contains 35% calcium (very high), 3.5% magnesium, 32 trace minerals
  • Used as a substitute for milk to match the calcium content of cow’s milk.
  • Used in agriculture as a biostimulant. Lithothamniom promotes vegetative growth, amplifies photosynthesis, and lowers watering needs.
  • Supports dental enamel remineralization.

Dulse (Palmaria palmata) 

  • Found off the northern Atlantic and Pacific coasts.
  • One of the best-tasting sea plants. They are very versatile as food. They can be used as whole pieces (good to marinate in lemon juice) or used as flakes or in powder form.
  • Provides a range of nutrients, including calcium, magnesium, folate, iron, Vitamin B5, and amino acids.
  • They absorb blue light and reflect red light.

Gracilaria

  • Rich in calcium, magnesium, phosphorus, iron, fiber, and Vitamin C.
  • Have high rates of nutrient uptake.
  • They have been a food source for centuries for humans, fish, and invertebrates.
  • Help filter out excess nutrients in aquariums.

Dragon’s Tongue Algae (Halymenia Floresia)

  • Have delicate, flame-shaped blades and are pink or red.
  • Grow in oceans worldwide.
  • They have antioxidant properties and antiviral activity.

Dumontiaceae

  • Indigenous to the Pacific coastal areas from Alaska to southern California.
  • Rich in vitamins, minerals, and protein.
  • They are packed with antiviral properties and help heal skin conditions such as eczema and dermatitis. Dumontiaceae are soothing and regenerating.
  • They have a high content of sulfated polysaccharides and moisture that help tighten the skin, reduce elastin degradation, and provide oxygen to cells. They are used in skincare products.

Agar Agar (Gelidium)

  • Indigenous to Japan (the best variety), Sri Lanka, and Indonesia.
  • They contain glose, a carbohydrate that is a powerful gelatinizing agent that can be used in place of gelatin, as a thickener, and as a clarifying agent in brewing processes.

Black/Purple Algae (technically red algae)

Nori (Porphyra yezoensis)

  • Found in open coasts with cold ocean currents.
  • Used to produce Nori (Japan) and Gim (Korea)
  • Nutrient-rich in antioxidants, vitamins, and minerals, including iodine, iron, magnesium, potassium, Vitamins A, B1, B2, C, dietary fiber, Omega-3 fatty acids, and protein.
  • Contains polysaccharides, polyphenols, and porphyrins with antioxidant, anti-inflammatory, hypolipidemic, and anticancer properties. 
  • Good in sushi rolls and ground up or flaked for toppings.

Laver (Porphyra umbilicalis)

  • Found in the northern Atlantic coasts of Europe and North America.
  • Similar to Nori.
  • Nutrient-rich, including proteins, polysaccharides, fatty acids, dietary fiber, carotene, Vitamins A, B1, B2, B12, C, choline, calcium, phosphorus, iron, magnesium, iron, zinc, and manganese.

Green Algae (Chlorophyta)

Green Algae are a group of chlorophyll-containing autotrophic eukaryotes (organisms that can produce their own food from the substances available in their surroundings using light (photosynthesis) or chemical energy (chemosynthesis). There are about 22,000 species of green algae.

Sea Lettuce (Ulva lactuca)

  • An edible green algae widely distributed along the coasts of the world.
  • They are mineral-rich, especially abundant in calcium, magnesium, and iron.
  • Dried sea lettuce is about 15% protein, including every amino acid.
  • Sea Lettuce has antioxidant and antiviral properties.

Other notable algae include the red algae Turkish Towel (Chondracanthus Exasperatus, CA, Asia) and the black/purple algae Grapestone (Gigartina papillata, N. CA).

These blood-building, nutritive sea plants are excellent food sources. Try Herbal Products & Development’s Essence of Sea Plants, a powder blend of 9 types of sea plants. Sea plants contain about 240 calories per 100-gram serving.

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Seaweed (Sea Plants)