diets

The Climate Impact Of Diets | Earth Wise

August 24, 2023 By EarthWise Leave a Comment

The food system is responsible for 70% of the world’s freshwater use and almost 80% of freshwater pollution. About three-quarters of the ice-free land area of the planet has been affected by human use, primarily for agriculture. Land-use change such as deforestation is a major source of biodiversity loss. What we choose to eat has a major effect on how the food system impacts the environment.

A comprehensive study by researchers at several UK universities has found that a plant-based diet yields one-fourth as much greenhouse gases as a diet rich in meat. Vegan diets produce 75% less heat-trapping gas, generate 75% less water pollution, and use 75% less land than meat-rich diets.

Just going to a low-meat diet cuts the environmental cost of a high-meat diet in half. Pescatarian diets perform better than low-meat diets, and vegetarian diets do even a little better than that.

There are a variety of reasons why many people won’t, can’t, or even shouldn’t become vegans. What should be learned from this study is that our dietary choices have a major environmental impact. So, taking actions like cutting down the amount of meat and dairy – which most people can do with relative ease – can be valuable.

There are many choices with respect to where we live, how we get from place to place, where we get our food, and, yes, what food we eat, that impact the environment. We are not all going to do the best possible thing in all these cases, but if we each make some choices that at least help, it can make a big difference.

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Vegan Diets Have One-Fourth the Climate Impact of Meat-Heavy Diets, Study Finds

Photo, posted November 5, 2017, courtesy of Stephanie Kraus via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fake Meat And Climate | Earth Wise

March 10, 2023 By EarthWise 1 Comment

Investors have poured billions of dollars into efforts to replace animal proteins with plant-based substitutes or even laboratory-grown animal cells. Replacing meats with these products is certainly a favorable development for the climate, but it is not likely to offset livestock agriculture’s climate and land use impacts anytime soon.

According to research at Stanford University, even optimistic estimates are that only something like 5% of dietary protein will come from these technologies by 2030. That just isn’t fast enough to put a real dent in the food-related emissions problem.

Stanford environmental scientist David Lobell suggests that there should be much more focus on reducing emissions of animal-based systems. There really hasn’t been much effort in this area because it is only recently that the climate impact of animal agriculture has been a topic of public concern. One problem is that it is difficult for investors to monetize investments in approaches for lowering animal agriculture emissions. These might include alternative feeds or supplements or vaccinations that inhibit methane-producing microorganisms in animals’ digestive systems.

Another approach to the problem is changing the mix of animal proteins in people’s diets. Chicken and pork are half as bad as dairy per pound of protein, and about one-tenth as bad as beef, in terms of emissions.

Dairy is a major issue. There has been quite a lot of progress in increasing the use of dairy-free milk, but over the past 40 years, Americans have cut their consumption of milk in half but doubled their consumption of cheese. Progress in dairy-free cheese has not been anywhere near as successful as that of dairy-free milk. But new products are entering the marketplace all the time.

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Is fake meat a real solution? Stanford expert explains

Photo, posted June 17, 2019, courtesy of Christolph Scholz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects On The Menu | Earth Wise

March 6, 2023 By EarthWise Leave a Comment

According to the World Food Programme, a record 349 million people across 79 countries are facing acute food insecurity. This constitutes a staggering rise of 200 million people compared to pre-pandemic levels. Nearly one million people globally are fighting to survive in famine-like conditions, which is ten times more people than just five years ago.

As a result, many experts contend that alternative or so-called novel food sources – such as lab-grown meats, seaweed aquaculture, and insects – will be necessary to help fight global hunger and global food insecurity.

Insects already form a significant part of diets in many cultures around the world. Insects are great sources of nutrients, including protein, vitamins, and minerals. But insects have yet to be embraced in any substantial way in western cultures… but that may be changing.

In fact, the European Union has now certified four types of bugs as food fit for human consumption. The larvae of lesser mealworms and house crickets recently became the third and fourth insects approved for sale as food in the EU, joining yellow mealworms and grasshoppers. Eight more applications are awaiting approval.

Insects are already a delicacy in many high-end restaurants around the world, and a normal and healthy part of diets in countries like Mexico and Thailand. Embracing insects as a food of the future will not only help in the fight against global hunger, but will also help to reduce greenhouse gas emissions and to slow species extinction.

In Western food markets, the so-called “yuck factor” remains the biggest hurdle to cross. But as the world population grows, the need for sustainable solutions in the food industry grows with it.

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Insects on the menu as EU approves two for human consumption

World Hunger Surged in 2020, U.N. Says

A global food crisis

Photo, posted April, 2014, courtesy of Shankar S. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plant-Based Foods And CO2 Emissions | Earth Wise

September 9, 2022 By EarthWise Leave a Comment

We often hear how eating locally-sourced food is a way to minimize the carbon footprint of our diet. But from a climate impact perspective, this only has a significant impact if transportation is responsible for a large portion of a food’s final carbon footprint. In many cases, the greenhouse gas emissions related to transportation make up only a small portion of the total emissions from food, and what we eat is far more important.

In general, beef and lamb have the biggest climate footprint per gram of protein. Plant-based foods tend to have the smallest impact. Pork and chicken are somewhere in the middle.

According to new research, U.S. food production could reduce its agricultural carbon footprint between 2.5% and 13.5% by embracing plant-based alternatives to beef. The study, from researchers at Cornell University, Johns Hopkins University, and international partners, found that most of the reduction would be achieved by decreasing the number of cows needed for beef production by two to twelve million animals. The research was recently published in the journal Lancet Planetary Health.

However, the researchers also found that acting to reduce climate change in this manner could have unintended consequences. For example, economic models from the research team show that the growth in popularity of plant-based beef could disrupt the agricultural workforce, threatening more than 1.5 million jobs.

But in the big picture, doing nothing will cost much more than doing something to slow climate change. Shifting diets away from meat and other animal products and towards more plant-based foods will help shrink carbon footprints and mitigate climate change. It’s a win-win for the planet and for human health.

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Plant-based ‘beef’ reduces CO2 but threatens ag jobs

Photo, posted November 27, 2018, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tepary Beans | Earth Wise

September 2, 2022 By EarthWise Leave a Comment

Tepary beans are an ancient crop native to the northern part of Mexico and the southwestern part of the U.S.. They have been grown in those places by native peoples since pre-Columbian times. They are still grown in Native American reservations in Arizona’s Sonoran Desert. One can purchase them from some small farms in that region.

What sets tepary beans apart from other beans is that they are among the most drought- and heat-tolerant legume crops in the world. They can be grown without irrigation under conditions that are not viable for other crops. They can be consumed by people like many other kinds of beans, and they can also provide forage for livestock with better nutrition content than many other plants. They seem to be a very attractive option for a crop in the changing climate. What is lacking, at present, is large supplies of tepary seeds to be planted.

Researchers at Texas A&M have been funded to bring tepary beans into modern cropping systems and diets. The goal is to develop tepary bean cultivars with high biomass and yield that are still well-suited to drought and heat conditions. Getting the beans to the point of widespread commercialization will take several years. The end result should be of interest to pulse growers, seed industries, and food companies across the U.S.

Tepary beans are higher in fiber and protein than most other beans. They come in several different colors, each of which has unique flavor and texture characteristics. The white ones have a naturally sweet flavor. The brown beans are slightly nutty in flavor and are similar to pinto beans. If the Texas program is successful, we may all be eating tepary beans some day.

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Tepary Beans Offer Producers A Low-Input, Climate-Resilient Legume Alternative

Photo, posted August 25, 2017, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Spending Habits And Carbon Emissions | Earth Wise

September 1, 2021 By EarthWise Leave a Comment

According to a new Swedish study recently published in the Journal of Industrial Ecology, men spend their money on greenhouse gas-emitting goods and services, such as meat and fuel, at a much higher rate than women.

The study looked at the carbon emissions created by consumption among categories like food, clothing, furniture, and vacations to see if households could reduce their greenhouse gas emissions by buying different products and services. The research team reviewed Swedish government data through 2012 and analyzed the spending habits of households, single men, and single women.

According to the study, single Swedish men spent about 2% more money overall than single Swedish women. But the stuff that the men bought created 16% more greenhouse gases than the stuff that the women bought. That’s because men were more likely to spend money on high-emitting categories, like fuel for cars, while women spent more on less-emitting categories like furniture, health care, and clothing.

For both men and women, vacations were a major source of emissions, accounting for approximately one-third of their total carbon footprint.

While the carbon impact of men’s and women’s diets were nearly equal, men spent more money on meat while women spent more on dairy. Both meat and dairy production are major sources of global greenhouse gas emissions.

The study found single people were responsible for more greenhouse gas emissions than married people or people in households.

According to the research team, people could decrease their carbon emissions nearly 40% by making more environmentally-friendly choices, including switching to plant-based foods and traveling by train as opposed to flying or driving when possible.

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Men have a bigger carbon footprint than women, climate study finds

Photo, posted June 17, 2012, courtesy of Stephen Ausmus/USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Prickly Pear As A Sustainable Crop | Earth Wise

April 6, 2021 By EarthWise Leave a Comment

The fruits and pads of opuntia, better known as prickly pear cactus, find their way into people’s diets in many arid and semi-arid places around the world. In Mexico, the pads are known as nopales and are used in a variety of dishes. The pears themselves are used in jams, salads, and juices.

A five-year study by the University of Nevada Reno College of Agriculture, Biotechnology & Natural Resources investigated the prospects for cactus pear to become a major crop like soybeans and corn and to help provide a biofuel source.

As the climate changes, dry areas are going to get dryer and drought issues will increasingly affect traditional crops.

The study looked at the particular opuntia species called the spineless cactus pear and found that it had the highest fruit production while using up to 80% less water than some traditional crops. Cactus pear can be used for both human consumption and livestock feed. As a perennial crop, once the fruit and pads are harvested for food, the remaining biomass can be used for biofuel production.

Corn and sugar cane are the most utilized bioenergy crops right now, but these use three to six times more water than cactus pear. The cactus pear productivity is on par with corn and sugar cane, but not only do they use a fraction of the water, they also have higher heat tolerance.

Over 40% of land area around the world is classified as semi-arid or arid. There is enormous potential for planting cactus for carbon sequestration. If nothing else, it makes great sense to grow cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops.

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Study shows cactus pear as drought-tolerant crop for sustainable fuel and food

Photo, posted April 16, 2020, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Non-Native Plants And Insect Decline | Earth Wise

January 15, 2021 By EarthWise Leave a Comment

Global insect populations have been in decline since the beginning of the 20th century. The decline accelerated during the 1950s and 1960s, and it has reached alarming levels during the past 20 years.

The causes of plummeting insect populations include habitat destruction, deforestation, climate change, light pollution, and the rise of industrial agriculture. This so-called insect apocalypse is being mirrored by a bird Armageddon because so many bird species depend on insects for their diets.

A still controversial, but increasingly likely factor in the decline of insect populations is the spread of non-native plants in agriculture, agroforestry, and horticulture. A recent study published in the journal Ecological Entomology presents recent data supporting the proposition that the widespread displacement of native plants is a key cause of insect declines.

Many insects depend on a limited number of plants for survival. In many cases, insects’ diets are restricted to a single plant family. When native host plants dwindle or disappear from an area, the population of insects that depend on those plants shrinks.

There are examples of insects that adopt introduced plants as food sources, such as silver-spotted skipper butterfly larvae feeding on invasive kudzu in the eastern U.S. But generally, the widespread incursion of non-native plants is harmful to native insect populations.

Non-native plants are especially popular for horticulture. Millions of acres of potential insect habitat have been transformed into food deserts for native insects. The authors of the recent study recommend that Americans should extensively include native plants in their yards to help preserve insect diversity.

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How Non-Native Plants Are Contributing to a Global Insect Decline

Photo, posted May 2, 2004, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

June 4, 2020 By EarthWise Leave a Comment

Many of us are aware of the infamous ocean “garbage patches” of floating plastic. The Great Pacific Garbage Patch is roughly the size of Texas. But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total. The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around. One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor. This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets.

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents. These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity. Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom. As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Environmental Injustice And the Coronavirus | Earth Wise

May 29, 2020 By EarthWise Leave a Comment

Cities and towns across the United States continue to wrestle with the devastating impacts of the COVID-19 pandemic and none have been hit harder than low-income and minority communities. Places like Detroit, Chicago, and St. James Parish in Louisiana have suffered from decades of economic inequality and pollution in their poorest neighborhoods and many of these same places have experienced some of the highest mortality rates from the virus.

Recent studies have shown a link between high levels of pollution and the risk of death from COVID-19. Pollution of various kinds are higher in low-income communities and communities of color. Such communities don’t have a strong political voice so that laws and environmental regulations are not enforced like there are in white, higher-income communities. Thus, these communities have highways, landfills, factories, chemical facilities, paper mills, and other pollution sources that communities with economic power – and therefore political power – manage to avoid.

People living in low-income communities and communities of color tend to have higher rates of underlying health conditions like diabetes, heart disease, and asthma. They have less healthy diets – more fast food and fewer grocery stores. Part of the reason these communities have a higher risk of mortality from COVID-19 infection is that many people have reduced lung capacity as a result of exposure to pollutants.

The Trump administration has been suspending enforcement of environmental regulations during the pandemic. Communities already affected by environmental injustice will bear the brunt of this decision. Groups like nursing home populations, meat packers, prisoners and the poor are suddenly highly visible. COVID-19 is exposing the real differences between the Haves and the Have-Nots in this country.

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Connecting the Dots Between Environmental Injustice and the Coronavirus

Photo, posted May 2, 2006, courtesy of Sean Benham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Narwhal Tusks And Stories Teeth Can Tell | Earth Wise

February 4, 2020 By EarthWise Leave a Comment

Teeth and particularly narwhal tusks are getting some unusual press recently when one of them was the weapon of choice to fend off the London Bridge attacker, which was a good choice according to Harvard dental researcher Dr. Martin Nweeia. Turns out that narwhal tusks have some pretty amazing physical features. They exhibit both extreme strength and flexibility at the same time. The narwhal is known as the unicorn of the sea, a pale-colored, medium-sized whale found in Arctic coastal waters and rivers. In males, the more prominent tooth grows into a sword like, spiral tusk up to 8.8 feet long.

Changes in the shape of teeth over time can tell us about climate change. Adaptations in horse teeth 55 million years ago from North America were observed and caused by changes in climate, favoring different food sources. The horses changed their diets from fruit to more favorable grasses and their teeth changed in response. For this same reason, the teeth of elephants adapting in different environments of Asia and Africa have different tooth forms. Both eat plants but Asian elephants, with more ridges on their teeth, eat larger amounts of grasses while African elephants, with wider spread ridges, eat more leaves.

Teeth have been used to link land mass theories like the Bering Land Strait Theory, hypothesizing that North America and Asia were once one land mass. The teeth shape and form of people on both sides of the Bering Land Bridge shared a common “mongoloid dentition” with unique features. And so, can the narwhal tusk tell us something about a changing Arctic? Scientists have discovered that the narwhal tusk is a giant sensory organ that is able to continually monitor its environment and has the ability to detect ice formation, and melt, both capabilities helpful for surviving in a changing Arctic.

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–Earth Wise acknowledges script contribution from Dr. Martin Nweeia of Harvard University.