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The benefits and risks of foraging your own food

Foraging gives people access to unusual foods as well as the experience of harvesting them directly from nature. But could kit jogo roletait be doing more harm than good?

On an unseasonably warm April evening, I stand on a beach in southern England, lifting a soggy lump of seaweed to my nose. It smells sharp and tangy. The hard, flat fronds are logged with tufts of green vegetation, sea water and sand.

Apparently, this one is best fried.

I am taking part in a seaweed foraging course on the Jurassic Coast, and as we clamber along the shoreline, with the Sun taking us into golden hour and mist forming above the sand dunes, our guide Dan Scott gives us some more cooking advice. "This one becomes mucilagenous – snotlike, a great word – when you cook it," he says, brandishing another sandy specimen.

As I pick the dry clumps of seaweed from some small rocks, then squeal in unison with a handful of the other course participants as we tease razor clams out from the sand with salt (and later release them), I ponder the bigger picture. Does foraging help us reconnect with nature? I've always assumed so. And what about the flip side? Is foraging good for the planet?

Scott is a member of the UK Association of Foragers and a guide with the company Fore/Adventure. He teaches us about seaweed anatomy (there's the holdfast, stem and fronds), how to harvest without killing the weed (cut it with clippers, leaving some of the length behind), and how to recognise which types are edible.

He doesn't recommend trying every edible option though. "Some of them are so maritime it's like having seawater in your mouth," he warns. Still, he says, the beach provides abundance. "If you have to survive on what nature gives you, it's much easier if you are by the sea."

Seaweed is considered a superfood, packed with important nutrients like potassium, iron and magnesium, and research has shown it can provide health benefits for people who are overweight or suffer from diabetes. Commercial seaweed cultivation is growing rapidly as countries seek to meet the growing demand for food and materials with a sustainable crop.

Foraging seaweed for your own plate is another thing altogether, however. Foraging involves gathering food from nature, where it has grown spontaneously rather than been planted. It is the oldest method used by humans to feed themselves and it is experiencing a huge resurgence. It is becoming an increasingly popular activity in the UK among ecologically aware people seeking to avoid fossil fuels, pesticides and herbicides, according to one study. In parts of the US, it's become so popular that certain national parks, such as Death Valley, have imposed limits on the number of berries and nuts people can gather per day.

Many of us practice foraging without really thinking about it – picking blackberries, perhaps, or wild garlic. When I visit Sweden, my home country, we pick sweet blue bilberries in the summer, eating them as we go, and red, tart, cranberry-like lingonberries in the autumn, collecting them in big plastic buckets. Lingonberries are not nice to eat raw, so my mum makes jam, enough for the whole year. Bending down close to the ground to gather the berries is quiet, mindful and almost hypnotic work. We bring sandwiches and flasks with tea.

Most of the time, though, I live in central London and get my food neatly enclosed in plastic off supermarket shelves. Often, it has travelled miles and miles and is made from plants I don't even know the appearance of. I find myself far away from the world that sustains me.

Foraging, though, even for people based in the city like me, can help connect people with nature, says Janani Sivarajah, an assistant professor at Université Laval in Quebec, Canada, who researches urban foraging.

"It brings people together, connects people to the land and to the forest," she says. "Our human livelihoods had been dependent on forest resources for many, many years before we started building cities, before we started [living] in concrete houses. I think it brings us back to our roots… I guess that's why people still do it."

My seaweed guide Scott agrees that foraging helps foster an appreciation for nature.

"If you teach people about edible things around them, they are much more likely to look after nature," he says.

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There are also foraging opportunities away from the coast. You can, for example, pick your own mushrooms in the forest. To learn about it, I call Bruch Reed, chief operating officer of the North American Mycological Association (Nama), a non-profit. His mushroom interest started when he was a young boy, he says. His family used to gather morels, which can only be picked for a few days during the spring in the US Midwest.

Later, living in New York, Reed foraged porcini and oyster mushrooms in Central Park. "People are getting meals out of that park. I did many times, because I was poor," he says. "Mushrooms [were] a luxury that I couldn't afford to purchase. [But in the forest,] I can just go pick and fill a basket and eat it. It makes me a king."

Nowadays, foraging is easier for wealthy people, says Steffen Hirth, a human geographer and sociologist at the University of Leeds in the UK, who has researched how urban foraging can contribute to sustainable cities. "In the past… the poor still had the skills to forage,” he says. "If you forage today, you do it because you're rich."

The practice is gaining popularity among the middle and upper classes at the same time as nature has become scarce and therefore more valuable, Hirth says. But it is not a solution to our sustainability problems, he adds – it is a commodity, a prized hobby.

"I think foraging is great. [But] I don't think that it helps in any way to shift the system towards a more sustainable state," he says. Most people also lack the time and knowledge for foraging foods like mushrooms, he adds.

In Canada, Sivarajah says, foraging isn't solely a middle-class hobby. "The groups that are involved [here] make up a very, very diverse population," she says.

Reed tells me that he mostly encounters foragers who feel they missed out on learning about the practice from their grandparents. "Essentially, they're rethreading that knowledge back into their life," he says. He adds that Nama members are becoming younger and that the organisation runs outreach programmes for underserved communities.

The research appears clear that foraging can have benefits for people. But I ask Sivarajah whether it also helps our environment – or can it cause more harm than good?

If people forage in large quantities and start selling berries and nuts commercially, it "depletes the local resource", says Sivarajah. We need to leave some for wildlife, too, she says. When hunter gatherer societies foraged, she notes, "the population wasn't all concentrated in one area. We were very much more dispersed".

To prevent resource depletion, Sivarajah says, foragers shouldn't remove large quantities from ecosystems. "If you do it for personal use, in a controlled manner, it can be beneficial" for the environment and our health, she says. "People are part of urban ecosystems." Foraging can also help control population spread and support natural growth cycles, and in some cases even manage edible invasive species, she adds.

In the US, there are state and federal laws restricting foraging of mushrooms, nuts and berries. In Ontario, Canada, foraging in provincial parks is prohibited due to the damage it can cause native species and ecosystems.

The National Trust, a UK conservation non-profit, issued a warning about the commercial picking of mushrooms and wild garlic, saying that people had taken too much and harmed fragile ecosystems. It recommends measures such as only taking one in 20 plants.

I ask my seaweed foraging guide whether he believes foraging is sustainable. "If 25,000 people come to these beaches and get their mitts on [the seaweed]... no," says Scott, adding that the course I am on is just for learning the ropes. "Just take a little for your dinner," is his general advice.

The question of whether foraging is sustainable is "very thorny", says Reed. "We have more and more and more people heading to smaller and smaller patches… [But] I grew up with the ethos of picking mushrooms as the least harmful thing that you do in the woods."

Reed is careful about where he picks and the impact his hobby has on nature, but still: "Mushrooms are an abundant resource," he says, "as long as forests are an abundant resource."

There are, however, also some health concerns to be aware of when foraging. One is pollution. "We are currently doing a study looking at how vehicular emissions like lead, zinc and heavy metals are being deposited onto urban trees and plants," Sivarajah tells me.

After reviewing dozens of studies, Sivarajah and her colleagues found that wild edible plants could have heavy metal concentrations higher than the safe upper limit in urban areas – but that these decrease by 10% if they are located 50m (164ft) away from traffic. "You should avoid heavy traffic areas for foraging because plants accumulate these bioavailable elements into their tissues, and some of the larger metals do stay on the leaves," she says. "If you do consume the [plants], you're consuming that [pollution]."

It reminds me of growing up in Sweden in the late 1980s, when people stopped eating fish, game and berries from areas affected by radiation from the Chernobyl disaster.

"You should avoid heavy traffic areas for foraging because plants accumulate these bioavailable elements into their tissues, and some of the larger metals do stay on the leaves, says Sivarajah. If you do consume the [plants], you're consuming that [pollution]."

Toxic elements are also a problem for the seaweed I am collecting on the beach. Seaweed can be high in?arsenic, lead and iodine – and while commercially grown specimens are tested for these substances, those we forage ourselves are not.

And then there are the poisons. Some of the mushrooms, berries and plants you might find in the forest can pose a serious health risk. When I ask Reed whether I should just walk out into the forest and start picking mushrooms I come across, he is aghast. "No, no. Oh, Lord. Let me be very clear... I have put in a lot of years of careful study under people who knew better than I do." Mushrooms, he reminds me, can be deadly. In September 2024, for instance, three people were hospitalised in Jersey, UK, after mistaking a death cap mushroom for an edible one.

To stay safe, you need more than a mushroom book, says Reed. "Books are great to have as references, but they're not enough. Join a club. Hook yourself up with a local person who knows, because there are deadly mushrooms anywhere in Europe and anywhere in the United States… and you cannot afford to make a mistake."

Three rules to remember, he says, are to not eat raw mushrooms, to watch out for little brown mushrooms (or LBMs), which are hard to distinguish from each other and may be poisonous, and to be wary of white mushrooms, which can be poisonous Destroying Angels. But these three rules are far from all you need to forage safely. Always consult an expert guide when picking mushrooms, berries and other plants.

As the Sun sets, I leave the Jurassic Coast. I take some seaweed home and dry it in the oven. It tastes quite nice. Standing in my kitchen, I look over at a supermarket jar of stuffed olives sitting by the sink, and eat two, relishing their perfect, briny flavour.

Suddenly, the gap between the perfectly presented, safe olives and the oven-charred seaweed, so difficult to obtain and unusual for me to eat, feels massive. The effort of collecting, preparing and gaining knowledge about my own food makes it clear to me how much I normally take what I eat for granted – I am even further away than I realised from the world that sustains me.

But my foray into foraging has already helped me reconnect with nature. I will continue doing it, but carefully, of course.

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