The Underwater World of Seaweeds
Seaweeds grown in a different world to land plans and have a unique physiology & chemistry from that of land plants in order to cope with their environment. Seaweeds are essentially multi-organism algae, sometimes referred to as macro algae. Seaweeds are the most ancient plants on earth, and many scientists claim the ocean is responsible for producing over 50% of the earth’s oxygen – much of this will be originating from the photosynthesizing algae abundantly present in the ocean.
Algae are critically important ecologically because they are the base of the ocean’s food chain, and thus the most densely nutritious.
Some seaweeds are microscopic, such as the phytoplankton that live suspended in the water column. Some seaweeds are enormous, such as giant kelp which grows in abundant underwater forests, and towers like underwater Redwoods from their roots at the bottom of the sea. Most seaweeds are medium-sized, come in colors of red, green and brown. To survive currents and conditions in the wild and changing oceans in which they thrive, they are tenacious, flexible fascinating plants.
Seaweeds – Vegetarian Food from the Sea
The name “seaweed” is really a misnomer, because a weed is often regarded as a plant that spreads so profusely it can harm the habitat where it takes hold. More recently, as the benefits of seaweeds are being better understood, they are becoming known as ‘sea vegetables’ or ‘ocean vegetables’.
What’s the Difference in Sea plant structure vs Land Plants?
There are thousands of varieties and species of seaweeds around the world. Different seaweeds grow at different latitudes and at different depths of the ocean. It is important to note that the vocabulary applied to sea plants is quite different to that of the land plants. It is helpful to know it to better understand information on the label. A seaweed’s physiology is quite different to their land counterparts -generally speaking:
- seaweeds have a holdfast, not a root. This helps them to anchor to rocks, the seabed or man made structures
- Seaweeds have a stipe, rather than a step or branch.
- Seaweeds have blades, rather than leaves. A cut blade is referred to as a frond.
- Some seaweeds also have bladders which help them to float. They could be filled with air or liquid less dense than sea water.
Wakame parts (image below) are used for various purposes in a wide range of dishes.
What about the Chemistry of Seaweed Compared to Land Plants?
- are well regarded as the best source of iodine (& essential co-factors) in nature
- are much more concentrated in nutrients (10-20 times) than land plants
- have all 5 essential nutrients necessary to a healthy diet protein, carbs, fat (albeit extremely low), chelated minerals, all vitamins (including B12) as well as prebiotic fibre
- have unique compounds that are being studied for their tremendous health-giving properties
- are at the extreme of the alkaline food scale
Apart from the considerable these eco engineers have on the planet, seaweeds support many essential functions in the body when eaten as part of a healthy diet and as a whole food. Read more about how in these links below: