Should You go Vegetarian?

Hybrid cars are a significant slice of the automobile market. These vehicles claim to cut emissions, they’re incentivised by lower levels of tax, and are cited as a cornerstone to cut our carbon footprint. But new research from Transport and Environment, and Greenpeace, which followed 20,000 hybrid drivers, suggests that in real world usage, the emissions from hybrids are up to 2.5 times higher than the tests would have you to believe. Adam Murphy spoke to Richard Black, who’s the director of the Energy and Climate Intelligence Unit, who wasn’t involved in the study, about why there could be such a big gulf in the numbers…

Richard - The mismatch seems to be the testing. It doesn't take place in real world conditions. And so you can test them in a lab, where you can go out on a test drive and that's fine, but actually people don't always use cars as they do in a test condition. And I remember there was actually a study out a couple of years ago in the UK, which looked at the behaviour of company car, hybrid drivers. So people who've been given a company car that was a hybrid. And what they found was that a lot of those drivers weren't actually using the electric components of this at all. They were simply driving around using the petrol engine. And then of course, if you do this, your emissions are not going to be lower than they would be from just having the petrol, or engine itself. In fact, they might actually be higher because you're lugging around a big battery and so on, that you're not using it's just extra weight.

Adam - So what happens then, just for a bit of background, in those kinds of testing conditions that makes them so different from how the real world is?

Richard - Obviously the tests are done in an artificial situation. So you can go out on a test drive, whatever it might be, a 20 kilometre drive, but the driver knows why they're doing that drive. Sometimes the motor industry conducts tests in the laboratory, where the cars are mounted up on rollers and you fit a hose over the exhaust pipe, and you catch emissions there. But again, your driving behaviour will be changed by the fact that you know that you're in a test. What's also emerged a few years ago, when we had the so-called Dieselgate scandal, was that at times, the testing labs, they seem to have a slightly unhealthy relationship with some of the car companies. Now, I don't know if that's the case in this instance with the hybrid test, but you know, that's something that I see that is there in the history of motor manufacturing in Europe. So I think the main reason is though the behavioural one. We all know, for example, when we jump in a car, we know that the emissions are going to be highest when the engine's cold and we should sort of warm it up. We don't always do that because sometimes we're in a hurry. We don't always drive as the old driving instructors used to say, as though there's an eggshell between your right foot and the accelerator pedal to conserve gas, we accelerate sharply, we brake sharply, we do all these things. So that's why this real world data, I think is so interesting.

Adam - Would you be able to tell me a little about the new policy decisions?

Richard - The hybrids question matters in the context of a policy that the British government is expected to make in the next couple of months, which will be, basically, a ban on the sale of new petrol and diesel engine cars. It's going to set a date when that ban will come in. The date could be as early as 2030, it could be as late as 2035. And basically, the main reason from climate change terms for doing this, is because transport emissions in the UK haven't been falling. This is an obvious way to do it. It's an absolute no brainer. If you want to get to the net zero target, there are calculations also suggesting it would be good for UK GDP. There's a whole range of businesses that are behind this. So one of the questions is then, do include hybrids in this ban. And the government has been subject to intense lobbying from parts of the UK automotive industry, which make hybrids, and have invested heavily in hybrid drive trains, to say that hybrids should be allowed. But obviously what this new research does is to say, well, hang on a moment. If hybrids aren't actually much cleaner in real life, than normal petrol diesel cars, why would you allow them to be continued to be sold after this ban comes in? Why wouldn't you go straight for pure electric cars, and pure hydrogen powered cars as well? So that's why I think this finding coming as it is, is particularly important, because it does very much play into the logic of this decision that the UK government is expected to announce in the next couple of months or so.

Back in July, we brought you the tragic news of a mass elephant die-off in Botswana’s Okavango Delta: hundreds of the animals were found dead. Originally, the cause was unknown, but, this week, Botswana’s Department of Wildlife and National Parks think they’ve identified the culprit: blue green algae in stagnant water. Phil Sansom spoke to conservationist Vicky Boult, from the University of Reading…

Phil - The first of the elephant deaths were reported back in March. Then from May, the carcasses started appearing in droves.

Newsreader - 169 elephant carcasses were found. By June, that number had risen to over 350.

Phil - Some look like they died incredibly quickly, keeling over onto their knees and faces. Others were reported looking disoriented, walking around in circles before eventually collapsing.

Newsreader - This is deeply troubling. Elephants don't just drop dead for no apparent reason.

Phil - For Africa's largest elephant herd, this unknown devastation looked like an existential disaster. Among all the possible reasons that were suggested, from starvation to dehydration, to deliberate poisoning, Niall McCann from the UK charity National Park Rescue mentioned the following on The Naked Scientists -

Niall - The least likely is that this is a natural toxin. Something like anthrax or a blue-green algae. If it was any of those things, we'd be expecting to see many other species also coming as well.

Phil - Well Botswana's government have just announced that this is indeed the reason.

Vicky - Tests have revealed that it is a cyanobacteria, which is a blue green algae that lives in water bodies.

Phil - [That was] elephant conservationist, Vicky Boult.

Vicky - Cyanobacteria are in many water systems across the world, but they become toxic when they bloom. We call it an algal bloom, which is just a mass generation of new cells, new bacteria. And we see these like blue, green scummy layers on top of water bodies, which is why it's called blue green algae. Usually that water body should be quite warm and nutrient rich and also slow moving or stagnant.

Phil - There's certain types of this blue green algae, this cyanobacteria, that produce neurotoxins. Toxins that hurt your nervous system. Make it start to shut down.

Vicky - You might see symptoms such as confusion, muscle weakness, muscle spasms. And that actually aligns quite closely with some of the symptoms that were reported in these elephants.

Phil - Interestingly, these blue green algae may have actually been the cause of some prehistoric mass elephant die-offs, which would be a bizarre turn of events because there's no record of them happening since. Until possibly now. And why here, in this part of Botswana in the Okavango Delta?

Vicky - The area where these elephants have died is very much enclosed from the broader ecosystem. There are fences separating Namibia from Botswana, but also a veterinary fence, which keeps wildlife and livestock from intermixing. The only other water source that's not a small stagnant pond is the Okavango pan handle. But for elephants to access that they have to move through human settlements and through farmland. So that cleaner water potentially is not readily accessible to them, which may have forced them to use these toxic water bodies.

Phil - No other wildlife species on the planes were affected by this toxic water. And even scavengers like hyenas and vultures that we're seeing feeding on the elephant carcasses showed no signs of illness.

Vicky - There's a couple of possibilities why we're not seeing that. Firstly, it might be that just due to an elephant's sheer size, they drink a huge amount of water and perhaps it's the amount of water and therefore the amount of toxins that they're ingesting. The other option is that elephants and elephant carcasses are very well monitored in Africa. And so it's possible that actually we're recording these dead elephants and not recording anything else because other things are harder to survey or less important to survey.

Phil - Both of these are just theories at the moment.

Vicky - I have seen a lot of people online, still quite skeptical. And I think that's mostly based upon the lack of transparency in the reporting from the Botswanan government. We have very little idea of exactly what samples were taken from the elephant carcasses, but also from the water sources and the broader environment. But we also haven't seen the pure lab results.

Phil - Like we reported last time on the programme when we covered this story, this is bad news for elephants as a whole, because back when researchers just didn't know what this was, there was a worry that this could sweep through the whole of the elephant population, and become their equivalent disaster while coronavirus sweeps through us. If it is the blue green algae, though, then we might hope that this is a limited area, not going to happen now that the temperatures are going down. But if this indeed is something that happened this summer because of warmer temperatures, then who's to say it won't happen next summer or the summer after that?

Vicky - It might be that we've seen the perfect climatic conditions for causing these blooms. Potentially a worry as we're moving into a warming world under climate change, we might start to see some of these algal blooms happening more often.

Is a plant based diet better or worse for us than a meat-based one? And, indeed, does it need to be an all or nothing thing: do we actually need to choose, or would a shift towards a more plant-based diet for at least some of our meals be a good compromise? Shireen Kassam is a consultant haematologist with the University of Winchester and she has an interest in the management of chronic diseases using plant-rich diets. Shireen spoke to Chris Smith in the studio, starting with what her own diet choices are...

Shireen - I eat a hundred percent plant-based diet. So other people would call that a vegan diet.

Chris - Okay. I just wanted to put that on the table - excuse the pun - because that way people kind of understand where we're coming from. Now in what ways do you believe that eating a plant-based diet is better for a person than a meat-dominated diet?

Shireen - Well the science is clear on this: the greater your shift towards a plant-based diet, minimising animal foods and processed foods, the healthier you are; and that's healthier bodyweight and significantly reduced risk of cardiovascular diseases, type II diabetes, and certain cancers. And more and more it's clear that those same risk factors are leading to dementia in later life, and if we got away from our conventional meat-based diet there would be less incidence of dementia in our society too.

Chris - So is that the case, then, that if one looks at populations such as in parts of Asia where meat-based diets are rare, that you see a correspondingly low rate of dementia, and a correspondingly low rate of things like diabetes, high blood pressure, stroke, and heart attack?

Shireen - Sure, if we look around the world where people are living the longest and the healthiest lives - and these regions in the world are called the Blue Zones - people are eating predominantly plant-based diets, 85-90% plant-based. And when scientific studies have been done looking at difference in the health outcomes for omnivores versus pescatarians, vegetarians, vegans; a stepwise reduction in the amount of animal foods you're eating, the better the health outcomes. So the science is absolutely clear on this.

Chris - But if someone says, well actually I quite like eating meat... and I mean, I'm one of them. You'd have to really twist my arm very hard at my back to dissuade me from occasionally frying up a rasher a bacon; it's just something I really enjoy doing from time to time. Would nevertheless a substitution of some plant-based food stuffs in place of a meat dish still translate into a health benefit? I don't have to go the whole hog... that's probably a bad choice of words isn't it! I don't have to go all the way in order to get some health benefit?

Shireen - No, absolutely. You don't have to be a hundred percent plant-based. But I would like to be clear that you can be perfectly healthy eating a hundred percent plant-based diet. So it comes down to a choice, a choice that we can all make, but any shift towards a plant-based diet is going to be better, as long as it's coming from healthy sources of whole plant foods, fruits, vegetables, whole grains; not the processed plant-based foods that are becoming increasingly available. And if you are going to choose your meat, I really would persuade you not to eat a processed meat like bacon, because it is a Group 1 carcinogen, it causes cancer. So make a better choice.

Chris - Whoops. Okay, well that's that off the menu then. But just coming back to the question of being healthier... because one does hear horror stories where you get people who say, "well, I'm going to turn over a new dietary leaf and I'm going to go down the plant-based diet route, I'm going to eschew meat," and then they wind up in their doctor's surgery with raging anaemia because they're not getting enough iron, and they can also get other micronutrient deficiencies. Is that just poor eating habits because they have embraced the lifestyle without knowing what they're doing, or that is there a high risk that this can happen to anybody?

Shireen - Well I think it can happen to anyone on any diet pattern. And as a haematologist I see plenty of people with iron deficiency, and as you've already pointed out, 94% of the population are not vegan or vegetarian; your risk of anaemia is no greater on a vegan or vegetarian diet. We're doing our current diet pattern very poorly. We're fibre deficient, potassium deficient, folate deficient; and we are eating too much protein from animals and saturated fat. A;l diet patterns need careful planning and we've forgotten how to do that. So if you're shifting a diet pattern, you need to do it with the knowledge and skills to do it properly. As you know, a vegan diet needs supplementation with vitamin B12, because it's not made by humans or animals; but beyond that you need to find your nutrients in the same way as you would on an omnivorous diet.

Chris - And how quickly would one begin to derive benefit? Because if you've been eating a lifetime of meat, is it the fact that if I were to switch to an exclusive plant-based... a) that might upset my system for a while, and b) would it actually be beneficial at a later stage of life to do that?

Shireen - Yeah, it's always beneficial to shift more towards a plant-based diet, but it depends on your starting point. As you pointed out, you can be healthy eating an omnivorous diet if you're doing it with lots of fruits and vegetables and other nutrient-dense foods alongside the meat. So you may not feel anything, but if you did need to improve your health as the majority of the UK population do, you'll find that it's easier to shed a few pounds in the first few weeks because you're eating lower calorie density foods which are more nutrient dense. For example, if you do have prediabetes or type II diabetes, within a few days your blood sugars will come down and you need careful management of that. Within two to four weeks, you'll find that your blood cholesterol level, if it needed to be lower, will come down to a healthier baseline. So yes, within a few days, weeks, months. And of course we're all talking a lot about gut health and the gut microbiome; that only takes a few days of shifting to a healthy plant-based diet to show an increase in the helpful bacteria. But it might be if you're feeling well and healthy, you don't feel any benefits; it's just you're benefiting your long term health, and of course the health of the planet too.

It’s not just our own health that can be improved by a shift towards a more plant-based diet, the planet benefits too. Chris Smith spoke to University of Manchester physicist Sarah Bridle, who’s also the author of the book “Food and Climate Change, without the hot air”, about how that shift might help the Earth...

Sarah - Well, in terms of all the cutting down forests, you have to do agriculture on the land and then animals and fertiliser on the fields and so on, and all the packaging and transport and everything, adds up to about a quarter of all greenhouse gas emissions currently coming from food. And that's increasing as there are more people eating more climate unfriendly foods.

Chris - And what fraction of that quarter is meat?

Sarah - It's about a half of that is coming from meat, depending on how you add it up. But yeah, it's half or more.

Chris - And why is meat so high? Because you think well, meet meat, we're going to eat that. So why would meat contribute so many climate change gases?

Sarah - Well, fundamentally we have to grow a lot of food to feed animals. So it takes about 16 times as much land to produce animal-based foods as it does to produce plant based foods.

Chris - Oh goodness. So in other words, what fraction, if you do the sums then, of the total land in agricultural use is just growing food for animals?

Sarah - About 80%. So about four fifths of the current agricultural land is currently being used to produce food for animals.

Chris - That's a lot, isn't it? So that means then if we all went vegetarian, and I'm not for a minute suggesting that anyone would embrace the idea but if we did, does that mean then that 80% of land would immediately be liberated because we wouldn't have to grow food for animals that we wouldn't want to eat?

Sarah - Very nearly yeah. I mean, we'd have to grow a little bit more plants just to make up for the calories and nutrition we'd lose from the meat. But even then three quarters, 75% of the agricultural land would then be freed up and we could use it for other things like maybe forest, for example, for pulling carbon dioxide out of the atmosphere. And that itself would also help to combat climate change.

Chris - You pointed at this when we first began to talk just now when you said, well, actually the human population, although it's only a quarter of our contributions, the human population is growing. So that quarter is growing as well isn't it? So it's continuing as the human population grows to get bigger and bigger and bigger as a contributor. So even if we did all go vegetarian, we'd still end up with food production being a very significant source of climate change gases.

Sarah - Absolutely. I mean, we have to do something about that three quarters, the rest of it. But if we were to stop burning fossil fuels, then food would then be the biggest contribution to climate change. And certainly, hopefully, we can reduce fossil fuel usage and it will be more and more important in terms of climate change in the next decade hopefully.

Chris - And what therefore is our best approach. How do we get a handle on that 25%, is the food industry. To bear down on that? And also if we do switch away from meat towards more plant based diets, how do we keep driving down the contribution to climate change gases from agriculture?

Sarah - Well, I really, really feel that there's not enough information that's easily accessible at the moment. So quite often people will just say, you know, for example, an average vegan diet causes about half the greenhouse gas emissions of an average omnivore diet. We can do these very, very broad generalisations, but actually in detail, of course, some farmers are working extremely hard to reduce the climate impacts of what they're producing. And so actually what I really want to see is labelling of greenhouse gas emissions on all food packets. And then we could actually go in there and reward the great work that's already being done by many food producers, but also that would mean that food producers themselves will be a lot more aware of their climate impacts and would work on that side as well to reduce the climate impacts of what's being produced.

Chris - Are all meats equivalently evil, or are some worse than others?

Sarah - In terms of climate impacts, there's a big difference between different types of meat. So if we look at something like beef and lamb, then they come from ruminants, they've got a particular type of stomach and about 5% of the calories eaten by a cow are burped out. Burps, very important that, not farted out, as methane. And so that's a very potent greenhouse gas. And so there tend to be over 40 times the amount of climate impacts. So if you get 40 times as much greenhouse gas emissions from eating a piece of beef than the weight of that beef, it's relatively high compared to something like say chicken, which is closer to 10 times. So there's about a factor of four difference between something like chicken and something like beef if not more.

Chris - How does dairy fit into the equation then, because obviously you've got to keep a cow to have milk. And therefore another staple of often many vegetarian diets is cheese, for example, which comes from milk. So how do the equations break down and shake down for the dairy industry?

Sarah - Yeah, so that's absolutely true. And in fact, if you, if you were to look at something like cheese, then it actually on average causes more greenhouse gas emissions than chicken. So if you were a meat-eater who ate only chicken and you replaced all of that chicken with cheese, it would actually be on average worse for the climate.

Chris - Hence you're saying, that's why we need the labelling.

Sarah - Absolutely. And it's just not so well known that there's these big differences.

Chris - And it's simple to say, well, I'll just start eating lots of fruits and vegetables, but a lot of that stuff doesn't grow in this country. So when one factors in the carbon footprint of transport, how does that affect things? And would that be reflected in the label on the supermarket shelf? I would say that will be difficult, wouldn't it? Because how would the supermarket know that I'm going to drive to the supermarket to buy that apple or something and therefore add my carbon footprint to it, or would we just have to live with the fact that extra carbon costs are all necessary?

Sarah - There's lots of different ways of doing the climate labelling. For example, often people don't count the consumer, you know what we do as citizens, within that number. So you might not necessarily have your car journey to the supermarket, but inside that label should definitely be all the transport that's happened to get that food to the supermarket. It very much depends on how that food has been transported. If the same piece of food were to come by ship versus by air, then flying it by air causes a hundred times more climate impact than sending it by boat. So as consumers, we don't usually know when we go to the supermarket, which things have come by air or by boat. And so it's really difficult to know, but if you have something that's come by air then it starts to get climate impacts comparable to those of some of the lower, lower impact meats and animal products.