What if I told you I’d found an edible source of protein that is cheap and easy to rear in captivity, releases fewer greenhouse gases in the process and yields a versatile, healthy food containing many of the vitamins and minerals we might usually obtain from meat?
If I then told you that potential food source was insects, you’d probably be disgusted. If you grew up in the Western world, that is. For nearly 2 billion people, insects are already on the dinner plate, and have been for centuries. Yet for some reason, in Western cultures insects are often considered less than palatable. If we could somehow shift this perception, however, we could change the world.
Entomophagy, as it’s more technically referred to, is the act of eating insects. And research suggests it might be healthier, greener and more economical than other sources of protein. Eating insects has the potential to ameliorate some of the negative consequences of global population growth and to bring food and livelihood to people in some of the poorest countries. But we’ve got to change our attitude.
As the global population soars, and over 800 million people go hungry each day, the search for sustainable ways to feed the world is becoming increasingly desperate. We are currently at a global population of 7 billion. This is expected to rise to 10 billion by 2060. Livestock now covers 30% of the planet’s surface. Another 13% is covered by crops. 70% of those crops go to feed our livestock. As the population grows, and we reach the limits of our technological ability to stretch the carrying capacity of Earth, this simply isn’t going to be sustainable anymore. If we cannot source more sustainable food supplies, more and more people will starve to death until our population agrees with the capacity of Earth.
Insects may be our best solution…
Insects are an amazingly efficient, cheap source of protein, carbohydrates, fats, vitamins and minerals. Because they are cold blooded (or ‘endothermic’), they use far less energy per kg than warm-blooded livestock like cows and pigs. To produce 1 kg of beef, you need 10 times more plant matter than you’d need to produce 1kg of delicious insect protein. They also use less water; 1kg of beef requires 20,000 litres of water to produce, while 1kg of cricket meat uses almost no water at all. And, they need very little space; tens thousands of crickets or mealworms can be grown in a room no larger than the average kitchen. So that means less feed, less water, less space. Their populations also reproduce incredibly quickly; a female cricket will lay up to 1,500 eggs a month, whilst in cattle on average 4 breeding animals produce a single market animal. When we factor this in, crickets are suddenly 20 times more efficient at converting feed into food.
Fewer Greenhouse Gas Emissions
Rearing insects (also known as minilivestock – awwww!) is also far less harmful to the environment than rearing traditional livestock. Insects produce fewer greenhouse gases and less ammonia than cattle or pigs. A major greenhouse gas, methane, is emitted in large quantities by cattle – because of their gut symbionts that help them digest the cellulose in all that grass – but most insects produce none at all. Notable exceptions including termites, cockroaches and millipedes, and the methane they produce comes from their gut symbionts, as well. Carbon dioxide emissions, too, are much lower from farming insects than animals – per kg from of ‘meat’, insects produce between 12% and 55% as much CO2 (it really depends which insect you’re talking about, though!)
Nutritous and Healthy
So why eat insects? They are cheap, sustainable, efficient and have a smaller footprint of greenhouse gases. I may have already mentioned it, but insect meat is also really nutritious. It’s rich in protein, fat (the good kind) and high in calcium, zinc and iron. It can also be a vital source of lysine in diets composed largely of grain (e.g. rice). And, insects also pose less of a threat in terms of disease – zoonotic diseases (which transfer from animals to humans), are increasingly becoming an issue as humans and livestock interact – but it is extremely rare for zoonotic diseases to be able to jump an evolutionary gap so wide.
And did I mention they were cheap? A single serving of cricket will cost you just £0.70, the same amount of mealworms just 6 pence. By contrast, a single burger will cost you about £1.
|Per Kg of Protein:||Sources of Protein|
|Feed Required||20 kg||1kg||2 kg|
|Land Required||0.02 ha – 0.5 ha||0.005 ha||0.0001 ha|
|Water Required||15,000 – 20,000 l||4055 l||~ 0 l|
|Greenhouse Gas Emissions||10 – 20 kg||1 – 2 kg||0kg|
|Cost||£7 – £10||£3 – £5||£0.50 – £6|
Attitudes to Eating
I recently conducted a survey* into people’s attitudes to sustainable food and dietary choices, and their views on consuming different types of food. When asked why they made certain decisions about their diet, 66% of people said that environmental issues were a concern, and 55% of people listed animal welfare concerns. Eating insects satisfies both these worries. The most important factor to people in deciding what to eat was animal welfare, with nutrition, flavour and price coming in next.
I paired food examples up according to their type (e.g. fruit and vegetables, pulses and beans, meat) and in terms of animal suffering, transportation distance, impact on the environment and the attitude of western society to eating them. In general, people found the most palatable food options to be fruit (e.g. strawberry), vegetables (e.g. broccoli) and pulses and beans (e.g. kidney bean), and the least palatable options were reptiles (e.g. snake, crocodile), fish (e.g. shark) and insects (e.g. spider). People would rather consume birds than ungulates (cows and pigs). Interestingly, people took real issue with consuming reptiles, with crocodile and snake (which, if farmed, would be better for the environment than beef) ranking lowest of all foods offered.
People tended to rate food products that were not associated with animal welfare concerns over those that were, and preferred those foods that traveled shorter distances and had a smaller impact on the environment. However, the largest difference in people’s palatability rankings was explained between foods deemed acceptable and those not.
Clearly, cultural and personal attitudes towards what we class as food and what we do not are hugely important in determining what we consider making part of our diet. Horses and cows are similar in terms of environmental impact and animal welfare concerns, however, horse was considered a far less palatable option than beef – presumably since it simply isn’t part of the standard western diet. So what can we do to change these perceptions? How can we persuade the western world that eating insects isn’t just OK, it’s a sensible solution to long-term food security and sustainability?
In December 2013 I was lucky enough to visit China, and I took the opportunity whilst in Beijing to try some of their famous street food – a fried scorpion. I must admit, even my western attitudes got the better of me a little – I opted for a small scorpion and decided the giant tarantulas on offer were a step too far. It wasn’t too bad. It tasted quite nice, mostly of what it had been cooked in, I suspect. The only unpleasant part was the crunchy legs! This problem can be easily resolved by turning insects into a source of everyday protein – simply mash up the insect into a burger or form in into any shape you like, really (think quorn!).
Is Eating Insects An Alternative for Vegetarians?
The reasons that make people decide to become vegetarian or vegan are varied and so it is impossible to generalise. But, for some veggies, are insects a viable alternative? Assuming a person’s motivation for being vegetarian is an emotional / ethical one – wanting to prevent suffering – then the question becomes can insects feel pain? This is a difficult question to answer. In humans, pain is a very subjective experience, composed of multiple different elements. It becomes increasingly difficult to apply the human concept of pain to more remotely related species; we are simple too different for it to be relevant. But, if we break pain into it’s constituent parts, it consists of a negative experience, which elicits an avoidance or withdrawal response – we feel a painful experience and we are motived to stop performing whatever action is causing the pain. The avoidance response is easiest to test in non-human animals – animals can be observed to see whether they move away from a negative stimulus (e.g. heat). Insects such as fruit flies, when tested, show a strong avoidance response to negative stimulation. However, avoidance alone is not sufficient to say something is experiencing pain.
We understand a little of the neuronal control of pain – nociceptors are thought to be important in the central processing of pain experiences in humans, and nociceptors have been cited as evidence for the experience of pain in many non-human animals such as cattle and fish. Nociceptors have not yet been convincingly confirmed in insects, however this may not mean very much. If insects do feel pain, the evolutionary origin of this would be so remote that they would likely have evolved an independent mechanism. The invertebrate central nervous system (CNS) is quite simple in organisation with less than 10% as many neurons as the nervous systems of large mammals. It is unlikely that they have any semblance of conscious experience, and it is doubtful that the experience of pain, as we know it, is possible for insects.
Further, from an evolutionary perspective we might not even expect insects to feel pain. Most insects have relatively short lifespans and limited capacity for learning. Thus it would be difficult for them to take advantage of the benefits of feeling pain within their lifetime, therefore making it pointless in evolving a system for feeling pain. Simply evolving inbuilt aversions to negative stimuli such as temperature or pH changes would be sufficient for short-lived species with a simple CNS – conscious pain is only really useful if it acts to alter future behaviour.
So, on the welfare front, it looks as though eating insects is just fine. And if the reason for a person’s vegetarian diet is sustainability, then insects come up on top – they are a highly sustainable option for protein in the future (see above). They are certainly better than another ‘ethical’ protein source – tofu.
I open this to debate – how would you feel about eating insects? Do you believe insects have sufficient sentience to suffer? Can you imagine replacing a beef or bean burger with a cricket one? Let me know your thoughts in the comments section below!
Featured image was used under a creative commons licence from Wikimedia commons. Original image by Leoboudv.