Carbon Footprint and Nutrition Styles
Food systems include all activities that carry foods from the field/farm to our tables. This includes how food is produced, processed, handled, marketed, and consumed. Research conducted in recent years show that what we eat has a great impact on the planet. A study supported by the United Nations in 2021 revealed that 34% of greenhouse gas emissions originates from food system.
More than half of carbon emissions of food systems originates from high demand for meat and dairy products. Moreover, industrial agriculture which is highly dependent on fossil fuels also contributes to these emissions. This causes significant environmental problems due to extreme water usage, soil erosion and chemical substance utilization. Especially the production of animal products causes emissions of strong greenhouse gases such as methane and nitrous oxide.
Inequalities in the food system are directly linked to bad diets and health. Today, many people across the world cannot access healthy foods or are unable to afford these. More than 2 billion people face food and nutrition insecurity while 820 million people are undernourished.
And climate change is projected to deepen these problems even more. In addition, the 6th Assessment Report of Intergovernmental Panel on Climate Change (IPCC) indicates that increasing levels of CO2 in the atmosphere will decrease nutritional quality of our food. This includes protein, iron, zinc, and some vitamins contained in grains, fruits, and vegetables. In other words, even more people will be under the risk of micro nutritional deficiency without these critical nutrients.
Discussions have been going on for some time about the impacts of decreasing the consumption of meat and dairy products and vegetarian or vegan dietary habits on the climate crisis. Food choices play a critical role for the ones who wish to contribute less to climate change.
Today, food choices present a challenging process. Factors such as fair and good agriculture and healthy nutrition determine our choices. Moreover, our nutrition styles have a significant impact on our carbon footprint. And there is a new study conducted at Tulane University that draws attention in this subject:
In this study six popular nutrition types have been compared in terms of both their food qualities and their environmental impacts. Researchers have compiled nutrition quality scores by using data from over 16,000 adult diets in the United States of America. They have evaluated popular diet types such as Vegan, Vegetarian, Pescatarian, Paleo and Keto.
So, which one of these different nutrition types ‘won’? Let’s review our nutrition styles and the impact of popular diets on our carbon footprints!
Most of us now know that red meat has a high level of carbon footprint. Therefore, it may not be surprising that keto and paleo diets which are based on meat products are listed as the least sustainable diets among the six diets that have been analyzed. In addition, it is again not surprising that these diets received the lowest score in terms of nutritional value.
As Andrew J. Yawn from Tulane has indicated in the press release regarding the study: “The keto diet, which prioritizes high amounts of fat and low amounts of carbs, was estimated to generate almost 3 kg of carbon dioxide for every 1,000 calories consumed. The paleo diet, which eschews grains and beans in favor of meats, nuts, and vegetables, received the next lowest diet quality score and also had a high carbon footprint, at 2.6 kg of carbon dioxide per 1,000 calories.”
Vegan diet has the least amount of carbon footprint with less than one quarter of the impact compared to keto diet thanks to 0.7 kg carbon dioxide for every 1,000 calories consumed.
Vegetarian diets follow vegan diets in terms of least carbon footprint levels, and they are followed by pescatarian diets. However, pescatarian diet receives the highest score in terms of nutrition quality from a health perspective. Pescatarian diets are followed by vegetarian and vegan diets in terms of human health.
Among the six diets, there is also the general omnivorous diet, represented by 86% of the survey participants. Omnivorous diets are both herbivorous and carnivorous diets. These types of diets are right in the middle in terms of sustainability.
However, hidden within the omnivorous category is the plant-based Mediterranean diet, which is the winner. The Mediterranean diet is a diet that avoids fatty red meat and focuses on local and seasonal vegetables. It has been observed that people who eat this style improve their carbon footprint and nutritional quality. Especially eating local and seasonal foods is perfect for reducing your carbon footprint!
In short, you don’t have to be vegan to reduce your carbon footprint. Tulane Research supports this fact. Researchers have found that one-third of omnivores eating a vegetarian diet on any given day is equivalent to eliminating an average of 340 million passenger car kilometers. Simply reducing your meat consumption can make a big difference to the planet.
There is no doubt that meat, especially red meat, has a high carbon footprint. Beef is responsible for 8 to 10 times more emissions than chicken production and 20 times more than nuts and legumes. Many people today are interested in switching to a plant-based diet. Research also suggests there are ways to improve your health and reduce your footprint without giving up meat completely.
According to the study, replacing 50% of animal products with plant-based products can have a significant impact on the natural environment. One of the biggest illusions about living a more sustainable life is that it is about all or nothing.
People who defend the planet act with a feeling of emergency, however this emergency commonly emerges as “I will not ever travel with airlines, I will transition to zero waste immediately, I will quit eating meat.” But the situation does not have to include an all or nothing mindset, and only decreasing certain behaviors can be enough to make some progress.
A study published in Nature Communications magazine showed that replacing animal products (pork meat, chicken, beef and milk) by 50% with plant-based alternatives can “decrease global emissions originating from agriculture by 31%, save forests and improve nourishment of millions of people”.
The researchers show that additional benefits can be gained in terms of climate change and biodiversity thanks to reforestation of the lands no longer needed by husbandry after meat and dairy products are replaced with plant-based alternatives.
Positive Impacts of Nutritional Change on Climate Crisis
Although global food supply constitutes less than 20% of energy supply, animal-based foods are responsible for most of the negative impacts on land usage, water usage, biodiversity, and greenhouse gas emissions in global food systems.
In short, the positive impacts that can be experienced by 2050 can be listed as follows if only individuals reduce their animal product consumptions;
1. Global agricultural fields would decrease by 12% instead of expanding.
2. Reduction in forests and other natural areas would almost completely stop.
3. Nitrogen input in agricultural fields would be almost half of the projections.
4. Water usage would decrease by 10%.
5. Greenhouse gas emissions can be reduced by 31% by 2050 due to carbon accumulation in the protected lands.
6. Malnourishment would decrease to 3.6% globally compared to the 3.8% in the reference scenario and the number of malnourished people would decrease by 31 million.
It has become obvious that promoting diets containing low levels of animal-based food is a critical component in reaching targets to reduce climate change, reaching health and food security targets across the world, and keeping natural resource usage in line with the limits of the planet.