 So I want to say first that I'm thrilled to be here and I really appreciate the organizers being willing to take a little bit of a risk on a couple of planetary scientists who do this sort of analysis basically for fun. So a little bit of background, Tess and I were grad students at Berkeley together and we had the opportunity to both take classes with and teach classes with Michael Pollan. And so we learned a lot about food sustainability in that environment. And then we began learning more about health and nutrition through our own journeys to good health. And through that avenue we found ancestral health and the symposium last year was sort of a, you know, religious experience for us. And so we noticed that there was a missing conversation going on and we really think that there is some work that can be done between the paleo community and the sustainability community that's really, really important. And so please listen to the whole talk before you throw anything at me. I know I'm talking about contentious issues but really my point here is to get you guys excited and interested in getting involved in sustainability and what that is gonna mean for us and of our food system. Okay, so with that food system, this is what we have. Okay, right now we devote an area larger than California to the growth of industrial corn, wheat, and soy. And I say industrial, to point out the fact this is not food that you can go and pull up a plant and eat. Okay, this is product that has been genetically modified to be super efficiently grown and we have to process it a great deal in order to get edible calories from it. In fact, we spend most of those calories to produce processed food that's all wheat based and sugars which we can drink. A lot of the food also goes to raising cows in confined feeding operations where they stand around in their own waste and get sick eating corn like we do. And that's basically where our calories go and then we have some that goes to ethanol and these numbers are a bit old. They were the easiest ones I was able to find that all use the same data. Right now we probably put a lot more corn to ethanol than we did when these numbers came out. Okay, so this food system requires a lot of inputs. It requires 128 billion gallons of water per day for irrigation. To contrast, we use two billion per person per day for domestic uses like showering. So it use a great deal of water, oil, land. We have to add chemical pesticides, herbicides, and fertilizers in order to continue to grow the same crops in the same land over and over and over. We also have to use a large number of antibiotics and hormones in order to grow the cows fat enough in a short enough amount of time that they are useful for us to eat. And it's been pointed out already, subsidies make this system marginally profitable for farmers but very profitable for food companies that buy this raw product that we grow. So this system also has a lot of outputs, greenhouse gases, animal waste that can contaminate food supplies, chemicals that, again, through runoff can contaminate water supplies. We have a lot of environmental degradation. Topsoil is eroding. We create a lot of sick people, a lot of sick animals in this system. We use so much antibiotics to help cows not die from feeding them corn that we now have drug resistant strains all around that we can't actually use antibiotics to cure ourselves. Again, because this is a very profitable industry for a very small number of companies, those companies in turn have a lot of power, more power than we feel like we have as consumers, which is a big problem. We also have a very vulnerable food supply by only growing a few species. We leave ourselves very vulnerable to pests and to viruses and all these kinds of things. But one thing that this system produces and produces very well is cheap calories. And we are constantly bombarded with this message that we need cheap calories because we have to feed the world. And this is a map from the United Nations showing the prevalence of undernourishment in the world. And you can see that it's very imbalanced. In places like North America and Europe and Australia, we basically don't have a problem with chronic hunger. Whereas in the global south, we have a big problem. In fact, we have 850 million people who are starving in the world today. And that's actually, that was an exciting number because it was down. However, interestingly, we already globally produce enough calories to have more than 2,700 per person per day. So why are people starving? Well, there's an imbalance. But we can look even at a finer scale than the whole world. So this is a table I put together using FAO Stat, which is a wonderful program that you can all access on the internet. And I've listed the 10 countries with the highest rates of undernourishment. You can see as high as 65% of the population in some of these countries are chronically hungry there, not getting enough food. Then the FAO is able to put together an average caloric requirement for each of these countries. So using demographics like age and sex, how many calories on average do you need to feed everyone in your country? And then they put together a food supply, which includes imports and exports and waste and all of these sorts of things. And what you'll notice if you compare these two columns, is that in almost every case, other than the two I highlighted in red, we have more calories available in the country than you would need to feed every person every day. And even in those two countries where it's not true, you're within a hundred calories. I mean this is not, this should not be mass starvation. So the take home point here is that we don't necessarily have too few calories. We have something else going on. So in the developing world, chronic hunger and malnutrition are actually caused by inequality and poverty, not by a lack of calories. The people who need them, who are poor are not getting them because they can't afford them or because they can't access them. And that is partly due also to political instability and lack of infrastructure. If there's no road and there's no bridge, you're not going to get into town to buy food. So all of these things factor into chronic hunger and malnutrition. We also have some really major nutritional deficiencies in the world. Two billion people lack iron and iodine. And greater than 200 million kids are so protein deficient that their growth is stunted. And another 200 million have vitamin A deficiency to the point that blindness is becoming a major problem in certain parts of the world. And then again, we hear this message a lot that the world population is going to continue to increase. So we're gonna have more demand and we may have fewer resources. So these problems, if we do nothing, will only get worse. So in the US we have a bit of a different issue. We have a lot of calories. And about 5% of households report actually having to reduce their food intake for economic reasons. The rest of us are pretty much able to get enough food. 70% of the average American's calories come from refined grains, added sugars, and refined vegetable oils. And maybe because of that, 36% of adults are obese in this country. 23 million have type two diabetes and another 79 million are at risk for diabetes. And a really interesting study by Coedoll found that poor people, even homeless people, do not have lower rates of obesity than the average population. So this is telling us a lot of things. It is telling us that we have plenty of calories and it's telling us that our food makes us sick. So here we have a big problem. People are not getting enough nutritious food. In the developing world, distribution is restricting calories, people are starving. In the US we're not getting enough nutrition and we have a lot of hidden calories that aren't necessarily alleviating hunger. They're just fattening us. In addition, conventional agriculture is failing. It's incredibly input and resource intensive in a way that isn't going to be sustainable over the long term. It also provides cheap calories that are really nutritionally poor. So this is not a particularly good system. So what do we do? Well, Big Ag has a solution for us, which is to feed the world, we need increased calories. And we can do that by increasing crop production by which they mean grain production. And to do that, we can use more of their conveniently sold technology and chemicals. And this solution fails in basically all of these ways. First of all, we've already discussed that simply increasing calories is not going to solve world hunger. We have enough calories. In addition, having more grains is not going to produce a healthy food. And so the same nutritional deficiencies are going to be present and the same sicknesses are going to be present. And the technology and chemicals is really troubling, partly because this is a very expensive way of farming. You have to buy a patented seed. You have to buy fertilizers and pesticides that work with those seeds. And so poor farmers tend to get into a cycle in which they become very much in debt trying to produce this food that they then can't eat. They have to sell it, export it. So this is not a good system for helping the impoverished get food. And again, it's unsustainable. And the so-called holy grail of GMO's drought-resistant grain has not materialized. So there's no real indication that they're going to be able to solve these problems. So what can we do? There are a few other solutions that have been proposed. One is that we could improve the efficiency of the big ag approach to food. And so there was a paper by Foley et al recently that said, well, we could be more intelligent about the way that we use fertilizer and the way that we irrigate. And that means that we could reduce the number of resources we need while still making the same number of calories. Or we could make more calories with the same number of resources. So they also, of course, advocate direct use of calories by which they mean don't feed our calories to animals that we eat, just eat the calories themselves. However, the crops that they include in this study that they're going to make more of with pure resources are these. And for those people in the back who can't see, these are grains, oils, and sugars. So in a different study that was rather interesting, they turned this question around a little bit and said, well, rather than trying to optimize only these few foods, why don't we take a whole swath of fruits and vegetables and grains and all these things and try to figure out which ones are the least resource intensive? And we could just eat those instead. And that would be helpful. And in this study, they were minimizing land use and also reactive nitrogen, which is the nitrogen that we put on as fertilizer that then can enter the environment. And of course they find that plant-only diets are far superior to mixed diets because we're talking about conventional agriculture. So all the resources that go into making the grain then goes into the animals. So of course the animals are going to be more resource intensive. But again, the most sustainable foods that they find are things that we don't want to eat. And in fact, in this diet, as you can see in this graphic here, the optimal diet includes 55% of the calories from grain and greater than 30% of their calories from oils. So an even better diet than we have now. All right, so these approaches fail because the focus is on increasing calories, which is not gonna solve our problems. We also really need to consider the nutritional value when we're deciding what is worth our resources. Everything we eat has an impact on the environment, everything that we do. And so we just need to be really smart about where we wanna spend those resources. It's probably not on corn. We also need to prioritize growing healthy foods with a lower impact. So trying to figure out how to make those foods more sustainable. And spinach is a good example of this. It turns out that conventionally grown spinach takes as much energy to produce calories as chicken does. Why in the world is that? It's because we wash our spinach three times in order to sanitize it before it can be bagged in those nice little bags and sent out to the grocery stores. So here's a method where I grow spinach in my backyard. The cost is almost nothing. We grow it conventionally, the cost is huge. So we can make very different decisions about how we grow food and do a lot better. So what is the actual solution? Well one is to empower the poor in order to mitigate hunger and leave this whole idea of calories aside. The second is to eat the least resource intensive healthy foods. So bringing the health and nutrition side of things into this optimization. We also need you guys to help define healthy which of course you're already doing. And we need to develop sustainable agriculture to minimize the cost of that healthy food. So what do I mean by sustainable agriculture? I'm talking about agriculture that doesn't use chemicals that uses practices such as crop rotation and crop diversity to add nutrients back into the soil to encourage pests that will pollinate things rather than trucking bees from Florida to California which is how we pollinate our almond orchards now. We also want animals to eat their natural diets and engage in their natural behaviors. We can combine plants and animals to create more closed loop systems in our farms. And this will produce food that's more in line with our ancestrally informed diets. So healthy food. And this is also a much more secure food source than monoculture crops. There are some issues with sustainable agriculture and some of them have been brought up already. One is the availability of labor and knowledge. We need people to go be sustainable farmers. It takes a lot more people than conventional agriculture. Also productivity can be difficult to quantify and it's not clear if we can make enough food. Although I would say since we have such an excess of calories now we could probably produce fewer calories that are healthy and come up with a better solution. Many small farmers face a lot of legal challenges and what they're trying to do and it still relies on unfair labor practices in many cases. So as a community what I ask of all of you is to help quantify the amount of meat that we really need for good health, especially red meat. Do we need to eat it every day? Can we eat it once a week? What are the trade-offs so that we know how many resources we ought to spend? We should also try to determine the relative need for meat versus seafood or as Marxist and likes to point out maybe bugs would be a fantastic way of getting a lot of protein. We should also be thinking about the potential for neutralizing anti-nutrients such as in legumes. And I'd really like you guys to come work with the sustainability community, which Mark calls Cistalio, to create macro and micronutrient metrics to help optimize health and environmental impact together. And I think we heard about the Kraken score already which I think would be really useful in this. We definitely need your help in fighting the big ag so-called solution which is basically to make more grains that we don't want to eat and refocus the discussion away from grains versus meat. And let me go into a little more detail on that. We spend a lot of time arguing about whether we should take these calories that we're producing in monoculture agriculture and consume them as calories or consume them as cows. This is a silly argument because we're basically wasting all of the resources that go into these grains because this is all we get out of it. Whereas we could be discussing the relative merits of a farm that creates a lot of fruits and vegetables and maybe some eggs and some chicken versus one that is more about animals only. I don't know which one is better or what the relative merits would be. Maybe we'd have half our farms doing vegetables and half doing cows, but that's really the discussion that we ought to be having. So as a consumer, I would encourage you to as much as possible buy food that is produced sustainably to help us promote the system. So organic, seasonal, farms that are employing polycultures that are using pasture-based methods, shop at farmer's markets, get involved in CSAs. As for animal products, please do not eat capo beef. This is a horrible environmental problem. And it turns out that eggs are actually pretty sustainable so that's a great way to get some animal product in your diet and eat a variety of cuts. If everybody is eating ribeyes, we're not going to be able to feed everyone, but you know, liver is great. So please eat a variety. Also, don't be afraid to advocate for better food. Grow your own food, add in some marginal foods and be sure to recycle your food scraps. This is a great way of using food that we would throw away in order to create new calories. And I'm running out of time. Okay, so let me just skip to the resources page so that if you're interested in any of these issues, feel free to go and find out some more information. Thank you.