Seaweed is two billion years old. There are three big families: green, red, and brown seaweed, and they are each very different.

Green seaweed moved on land half a billion years ago and gave birth to all the vegetation we have now. It is genetically closer to an oak tree than it is to a red seaweed. The difference between red seaweed and green seaweed is bigger, from a genetic perspective, than the difference between a fungus and an elephant. This very wide area of genetic diversity offers an equally diverse range of applications.

These revelations were shared by Vincent Doumeizel, author of ‘The Seaweed Revolution, in our recent webinar hosted in partnership with Bright Tide and the University of Plymouth. The webinar covered the incredible range of applications of seaweed and reflects its role as a vital part of a sustainable ocean economy.

Edited highlights
  • Humans have a long history with seaweed

    In the past, humans ate a lot of seaweed. It has been scientifically proven that, for our brain to mutate from apes to Sapiens, we must have ingested a lot of polyunsaturated fatty acids, which are only present in seaweed and fish oil. We are what we are because we used to eat a lot of seaweed over the last 140,000 years of our existence.

    We have lost that intimate connection with the ocean over the last 2,000 years. We started to develop and grow our food on land - and became very good at it. But we’ve reached our limit. So, we need to get back to our history.

  • It’s time to re-establish a relationship with the ocean

    The ocean covers 70% of our planet and contributes, in calories, to less than 2% of our food. We haven’t yet started to properly use the resources from our oceans.

    In contrast, on land, we’ve reached the maximum yield we can produce. With the accelerating urbanisation of the world, we have no arable land left. We have 1 billion people starving and 300,000 additional mouths to be fed every day.

    Plus, the food industry is soon to overtake energy to become the biggest contributor to greenhouse gas emissions. It is the biggest contributor to water scarcity, soil depletion, and various social issues, including modern slavery.

    If we limit ourselves to the land, we will never succeed in creating fully regenerative agriculture. Our ecosystem on Earth is based on the ocean; life was born in the ocean. If you forget about the ocean, you will never make anything regenerating.

  • Regenerative agriculture starts with seaweed

    When it comes to aquaculture, we’re still in the Stone Age; we’re essentially still hunter-gatherers. We are getting some food from our oceans, most notably fish, but we know that we are soon to fish the last fish. We have destroyed 50% of the ocean ecosystem.

    We’ve begun some aquaculture, for example, salmon farming. But we’ve started at the highest trophic level - at the end of the food chain. As a result, we’re feeding salmon from land resources and overfishing resources. So, we’re not seeing any improvement.

    To start a regenerative industry in the ocean, we need to focus on the lowest trophic level. Seaweed is what feeds phytoplankton and small fish, which feed the rest of the chain. If you want to start the rebuild the ecosystems at sea - instead of destroying them - seaweed is a very good place to start.

    It doesn’t need land. It doesn’t need pesticide and of course, you don't need to water it. It’s almost a free resource.

  • Seaweed is already a fast-growing industry

    Seaweed cultivation isn’t a new concept. China, Japan, Korea, and Indonesia started widely harvesting seaweed 50-60 years ago. 35 million tonnes of seaweed are cultivated every year. It’s a $15 billion sector, growing at 10% a year.

    Even in the West, we consume seaweed - as a texturing agent - five or six times a day. 70% of processed foods contain seaweed. It’s in toothpaste, in meat, in ice cream. But those current applications don’t tap into the true potential of seaweed.

  • Seaweed is a superfood

    Seaweed is full of protein - up to 40% protein. It has a lot of iodine, zinc, and omega-3 long-chain fatty acids, which are the most essential for our brain.

    Plus, it’s resilient. When you dry seaweed, you don’t lose any of the nutrients in it. It doesn’t require cold chain and can keep for months. That’s very good news for emerging countries and for our climate goals.

  • As animal feed, it can hugely reduce methane emissions

    In animals, seaweed can benefit immune systems and reduce reliance on antibiotics.

    Another fantastic benefit is cutting methane emissions by ruminants. Methane is a massive 25% of global emissions, and it is 80 times more damaging to the atmosphere than carbon.

    There is a type of seaweed called asparagopsis taxiformis. If you mix this into the diet of a cow at just 0.02%, you can cut methane emissions by up to 90%. If you give just a few grams of this small, red seaweed to every ruminant in the world, the impact, in terms of greenhouse gas emissions, will be the same as if you stop every car trip on the planet, overnight.

  • New medical benefits are constantly being discovered

    A lot of medical innovation comes from seaweed. Drugs made from seaweed have been shown to treat Alzheimer’s and dementia. There is a treatment in phase three testing for cystic fibrosis. Seaweed is anti-inflammatory, antiviral, antibacterial, antifungal, analgesic, and it's a natural prebiotic that improves our microbiome.

  • Seaweed can replace plastic, cardboard, and cotton

    There’s a company in the UK called Notpla that creates plastic-free, edible packaging from seaweed. According to Notpla’s calculations, we could replace all the plastic we have in the world with just only 0.03% of the kelp we have.

    A German company is using seaweed to replace cotton. Why? Well, cotton accounts for 2% of land agriculture, 25% of the pesticides used in the world, and 10% of the herbicides. Synthetic fibres are the biggest contributors to microplastic pollution. Seaweed is a great alternative to both.

  • We still need to address some significant obstacles

    One of the biggest issues we face is a lack of knowledge about how to cultivate our endemic species. There are 12,000 types of seaweed in the world today and we know how to cultivate 10 to 20 of them.

    We also need to address problems with restrictive food safety regulations and environmental regulations. It's amazingly difficult to get a licence to grow seaweed. In California, it’s easier to get a licence to pump oil into the ocean.

    Another issue is that seaweed is a very fragmented sector. We have a lot of visionary pioneers, but they are working in isolation.

    To accelerate change and attract investors - because we need a lot of investors - last year, we formed the first global coalition of seaweed stakeholders, called the Safe Seaweed Coalition. For anyone wanting to invest, or just interested in learning more, is a great place to start.

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