The recent report by the advisory committee to the USDA dietary guidelines has certainly caused a media stir in the past week or so. There’s a lot of nutritional common sense in the report – eat more fruit, veg, and dairy, reduce carbs and sweetened drinks/snacks, and moderate alcohol intake. Yet there’s a kicker – from both a health and a sustainability perspective, Americans should apparently be guided to consume less animal-based foods.
I’m ashamed to admit that the picture to the left is of the lunch table that a media colleague and I left last week – after spending an hour lamenting the fact that in the US, 40% of food is wasted (30% globally). Admittedly, that waste isn’t all down to restaurant portions (in our defense, we both had to fly home, so doggie bags weren’t an option) – however, according to FAO data here, consumer waste accounts for anything between 5% (in Subsaharan Africa) and 39% of total waste (North America and Oceania). The difference (anything from 61% – 95%) is made up from losses between production and retailing.
Losses from production to retail comprise by far the biggest contribution to waste in the developing world, which makes absolute sense – if food is your biggest household cost and hunger is a constant and real danger, the concept of wasting purchased food would seem ridiculous. In the developing world, a myriad of factors play into food insecurity including low agricultural yields, lack of producer education (particularly for women, who are often the main agricultural workers), political instability and military conflict (Pinstrup-Andersen 2000). However, possibly the biggest threat to food security is a lack of sanitary and transport infrastructure (Godfray et al. 2010) – building a milk pasteurization plant is a great opportunity to improve shelf-life, but can only be effective if producers have the facilities to refrigerate and transport milk. Improving tomato yields can reap economic dividends, but if they are transported to markets packed into plastic bags on the back of a bicycle, the wastage is huge. I’m not going to pretend I have the solutions to global food wastage, but what can we do in our own households?
Just as our grandparents learned during WWI and WWII – when food is scarce, you make the most of every single drop of milk or ounce of grain. Yet in the modern developed world, we can afford to waste almost 2/5 of our household food through not understanding expiration dates (cheese does not spontaneously combust into a listeria-ridden ooze at midnight on the day of the expiration date); throwing away the “useless” parts of food waste (radish leaves and wilted celery are actually really good in soup); or simply buying more than we need. In a recent study of greenhouse gases associated with US dairy production, the carbon footprint of a gallon of milk was increased by almost 20% simply because of the amount of “old” milk that consumers poured down the sink each day.
To go back to the picture above, it’s tempting to blame the restaurants – portion sizes tend to be huge, so in this carb-conscious world, it’s not “our fault” if we forgo the last 500 calories by leaving half a plateful of potato chips – they should have just served a smaller portion in the first place, right? Well, maybe. If we’re feeding dairy cows or beef cattle and seeing more than 5-10% feed unconsumed, we’ll reduce the amount fed. I’m sure that exactly the same practice would pay dividends in the restaurant world, and I’d be willing to bet that they could charge exactly the same price.
I spend most of my time myth-busting, showing that the modern beef and dairy industries are far more efficient than the farming systems of 40 or 70 years ago and that we now produce more food using far fewer resources. However, are we really feeding more people if we’re wasting 40% of our food? To suggest that we return to a practice from the WWII era feels almost heretical, but here’s an idea – rather than defining “sustainable” systems as those producing artisan cheeses from heirloom breeds cared for by hemp-wearing liberal arts graduates, why doesn’t every restaurant (or suburb) have a small herd of backyard pigs? Collect the waste food, boil it for 30 min to avoid disease issues, feed to pigs, produce bacon. What could be better? Admittedly, my mother country has banned this practice (I’m beginning to wonder if anything will be permissible in Europe soon), but let’s start the pigswill revolution! Doesn’t “You don’t have to eat that last potato, it’ll make some really good bacon and help us feed those 1 in 7 kids in our local area who don’t have enough food” sound more realistic than “Think of all the starving orphans who would enjoy your PB&J sandwich” (to which the continual smart-a** answer was “I’ll just mail to to them). Let’s do what the livestock industry does best – recycle waste resources to make safe, affordable, nutritous meat!
One of the main criteria for publishing scientific research is that it should be novel, yet not a week goes by without yet another paper concluding that we have to reduce meat consumption in order to mitigate climate change. That’s the headline in media coverage relating to the latest paper from a researcher at the The Woods Hole Research Center (published in Environmental Letters), which examines nitrous oxide emissions (a highly potent greenhouse gas (GHG)) in 2050 under various scenarios.
It’s an interesting paper, not least for some of the assumptions buried within the model. Based on data from the FAO, the authors assume that meat consumption will increase by 14% in the developed world and 32% in the developing world by 2050. Coupled with the predicted population global increase (from the current 7 billion to 8.9 billion in 2050), it’s not surprising that a 50% reduction in meat consumption would be predicted to have a significant effect on total GHG. It’s rather akin to suggesting that each person will own two automobiles in 2050, so we should reduce car manufacture.
However, the more striking result is buried in Figure 1, showing that if efficiency of manure management and fertilizer application were improved, this would have a more significant effect on GHG emissions than reducing meat consumption. Given the considerable improvements in cropping practices, crop genetics and yields over the past 50 years there is absolutely no reason why this should not be achieved in the next 40 years.
Alas, a headline suggesting that agriculture needs to continue to improve manure and fertilizer efficiency just isn’t as sexy as the “eat less meat, save the planet” message so often propounded by the mass media. They say that bad news sells – it’s a shame that the lay press are so enamored with messages that denigrate ruminant production, rather than taking a broader look at the options available for mitigating future climate change.
*Thanks to Jesse R. Bussard for bringing this one to the forefront of my “to do “ list.
A recent article by Andrew Jack in the Financial Times (the iconic pink-colored newspaper carried by all self-respecting business men on London tube trains each morning) reports that developing countries in Africa will be responsible for the greatest increases in population growth over the next 90 years, with the global population predicted to hit 10 billion by 2100. Given the number of dire predictions currently being bandied around regarding population increases, food demand and climate change it’s easy to become blasé and dismiss it as just another issue that will be solved by the next generation. After all, what difference can we possibly make to rural communities in developing countries?
Rises in per capita are predicted for developing countries over the next century and as Andrew Jack notes, increasing affluence results in improved healthcare, urbanisation and a decline in birth rates. Nonetheless, this pattern is not being currently being exhibited by regions in Africa and S. Asia, which are unable to improve per capita income as population increases overcome economic growth.
So how do we curtail the rise in population growth? Even in a developed country such as the USA, mentioning the politically-charged phrase “population control” often leads to an uncomfortable silence, images of an Orwellian constraint on family size (1 child good, 2 children bad?) or debate over the rights and wrongs of abortion. Yet simply providing access to contraception, considered to be an inherent human right by many women in the developed world, could conceivably (pardon the pun) improve future sustainability.
Reducing the number of children born in developing countries would improve female health and lessen the burden on economic and environmental resources placed by increasing population size. This would be a crucial step forwards in mitigating future food shortages, yet it does not solve the underlying problem. One of the major drivers behind population growth is parental reliance on support from the younger generation. As discussed in Jared Diamond’s excellent book “Guns, Germs and Steel“, higher birth rates potentially allow for a greater number of children to work on the land and improve societal stability. However, the promise of future affluence is a major stimulant that causes young people to migrate from rural areas to urban regions that are already suffering from significant overcrowding.
A considerable yield gap exists between developing and developed countries, both in terms of animal and crop production. If productivity could be improved and the yield gap reduced, food security would improve in rural areas with positive effects on per capita income and infrastructure, and potential reductions in the number of inner-city migrants. Nonetheless, the major question remains unanswered – how to improve productivity?
If we use dairy farming as an example, a recent report from the Food and Agriculture Organisation noted a negative relationship between productivity and carbon footprint – as we move across the globe from developed to developing regions, productivity decreases and the carbon footprint per kg of milk increases (see graph). Carbon can also be considered a proxy for land, water and energy use, thus reduced productivity increases both resource use and environmental impact. The logical conclusion would therefore be to implement systems and management practices currently seen in N. America, Europe and Australasia in an attempt to educate farmers in S. Asia and Africa. However, sustainability cannot be improved by implementing a one-size-fits-all solution, but calls for a region-specific approach.
Identifying traits within indigenous and imported animal breeds and plant varieties that will make the best use of available resources allows development of production systems that match environmental, social and economic demands. Further implementation of continuous improvement and best management practices in developing countries is crucial in order to improve affluence, reduce population growth and mitigate environmental impact both now and in future. However, this is not a situation that can simply be solved by improving yield per acre, but requires a multifactorial approach coordinating population control, education, food security and human health and welfare. Providing contraception without a concurrent effort to improve agricultural productivity will fail in its prophylactic intent to control either population growth or world hunger.