The 21st century has brought with it a number of major challenges – war, terrorism, disease – you name it, we got it. But one issue stands head and shoulders above the rest: food. Or, more accurately, how we can create enough of the stuff to adequately nourish ever greater numbers people.

The global population increases by around 75 million – ten million more than the population of the UK – every year. Since 1800, the number of people on the planet has shot up from one billion to seven billion, and there’s no sign of a slowdown. By 2050, the figure could be approaching ten billion, according to many experts.

Quick population increases obviously put a lot of pressure on food stocks and are a major incentive to improve agricultural processes as well as to come up with new ways of sourcing food. But it isn’t the only factor fuelling the problem.

Another – counter-intuitively – is the fact the world is getting richer. Wealthier people want a varied diet and they eat more meat, both of which increase the resources required to fill a plate. The average person in China currently consumes about half the meat of the average American, but tastes are changing and as the country’s middle class balloons, so does its appetite.

This is having a profound impact on the consumption of water – another precious resource – with supply failing to meet demand in the irrigation of crop fields, particularly in developing countries. Soil fertility is being eroded by intensive farming, while climate change is playing havoc with harvests.

This could be potentially devastating for people in poorer countries, but it is also a cause for concern in the world’s powerhouse economies. Consider Las Vegas, a city with no local water supply, or Mexico City, an arid city with a population topping 20 million.

Even London gets a lot less rain water than we all like to joke about, and politicians have considered ways of shipping water from rainier parts of the UK, such as the North of England and Scotland, to replenish fields in Southern England.

All that, and the world’s population is moving to cities in droves, creating logistical and technical problems for food production and distribution, and potentially also causing populations to fall in areas where food is grown.

Solutions to these baffling problems will come from entrepreneurs, free thinkers with the gumption to turn ideas into reality. Investors should take note of the new and growing businesses that aim to tackle the growing crisis, because there are few greater needs in the world today.

Existing ideas include vertical farms, which are multi-story skyscrapers for growing vegetables, perfect for producing food without the need for enormous open tracts of land. Also insect-based foodstuffs, which deliver a lot more protein than cow or chicken, yet cost a fraction of the price to produce.

There are also solutions that could reduce food waste, nearly three trillion pounds of which is thrown out each year. In the UK, an app startup called Digimeal, founded by sisters Risha and Sumita Jindal, shows students how to make dinner with simple ingredients and leftovers they might otherwise leave to go off.

In the US, Kimbal Musk, brother of billionaire Elon, has founded a not-for-profit business installing ‘Learning Gardens’ in schools – 300 so far.

He predicts that vegetable-based meat alternatives will become more popular as meat production becomes unsustainable; he says more food will be made locally and that governments will give more incentives to food producers.

Whatever the future throws at us, food shortages will be a critical problem to solve. Businesses are researching solutions right now and they need your investment to make progress. The material value of an innovation that stops people going hungry is obvious, but putting your money behind a business that saves lives is priceless.

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