9 February 2022

Over time, humans have eaten 6,000 plant species. Now, we eat just nine

By expanding our diet, we can protect species and landscapes from the relentless march of monoculture.

Just before Christmas, I was lucky enough to find myself hiking in the Kenyan bush in the company of two local Maasai. They were talking about the possibility of seeing cheetah; I was more interested in the small, spiny trees all around us after one of the guides, Peter, told me that, as well as giving fruit, the desert date’s viciously thorny branches can be steeped in water to treat malaria. “You sit over the bowl with your head covered and you sweat, and after three days the fever is gone,” he explained.

As we walked, I chewed on a piece of wood he’d cut from the toothbrush tree, Salvadora persica – recommended by both the World Health Organisation and the Prophet Muhammad to encourage oral hygiene. Peter said many people still trust it “more than Colgate, which doesn’t taste good”. The tree’s root, meanwhile is “very bitter” and “very good for you” when boiled with goat meat. His colleague Edison chipped in, telling us his father, who worked as a ranger, used to bring rhino dung home to infuse soup with the power of the plants the animals had eaten.

As famous for their dairy-rich diet as their striking dress, the pastoralist Maasai also traditionally consume wild plants, fruits and tubers from the land on which their cattle graze, though these days they supplement this with cereals such as maize meal, and commercially traded foodstuffs. Jackson, a trim 33-year-old warrior, told us that he’d given up Western food as it made him fat. His favourite meal was blood and milk, taken together. “It tastes a bit like yoghurt… I have it maybe once every two months when I am in my village and I need energy.”

Not that blood is on the menu for anyone right now; the rains have failed, and the guides are worried about their herds. “We don’t have bank accounts… When you get cash you buy a cow or a goat, and then when you need money you sell it.” Losing them to drought is a disaster.

I was reminded of how the very modern Maasai seemed to have a use for almost every tree or bush in their native landscape while reading an account of time spent with the Hadza tribe of Tanzania, in the journalist Dan Saladino’s recent book Eating to Extinction. One of the world’s last remaining hunter-gatherer societies, the nomadic Hadza consume around 600 varieties of plants and animals from the wild. Of the 6,000 plant species the human race has eaten over time, Saladino reports, we now largely confine our consumption to a mere nine, with half our calories coming from just three: wheat, rice and maize. Our diet, he says, has undergone more change in the past 150 years than in the preceding million.

The benefits of expanding the menu are several: maintaining cultural traditions and feeding our own gut flora for a start; the more diverse the food we eat, the more diverse the trillions of microorganisms we host. Typically, the Hadza gut has 40 per cent more species than its UK counterpart – an abundance associated with reduced incidence of both obesity and disease. But narrowing what we consume also puts global food security at very real risk, as we rely more and more heavily on a handful of crops, all vulnerable to disease, climate change and other environmental threats. The tragic lesson of the Irish Famine, for example, makes the dangers of a monoculture painfully obvious.

Clearly, eight billion people can’t support themselves solely through wild food; even the traditional Hadza way of life is under threat, with only a small proportion still living as pure hunter-gatherers. But, Saladino claims, one billion of us do derive a portion of our diet from the wild, whether through eating truffles in a fancy restaurant in Milan, gathering garlic in a Birmingham park, or snacking on crispy crickets in a market in Laos. In the process we help to protect those species, and the landscapes in which they thrive, from the relentless march of monoculture. Wherever we live, we still have the option of disrupting the narrative. To quote the professional forager Miles Irving, “eat a dandelion growing on your garden lawn. It’s a revolutionary act.”