As I’m sure you’re well aware, human activities put a tremendous strain on the environment. You may also be aware that each major sector of society has its own environmental impact—from our transportation system, to energy generation and consumption, manufacturing and industrial processes, waste management, agriculture, and everything in between. What you may not be aware of, however, is just how much agriculture impacts the environment.

Agricultural practices are responsible for about 18% of all global greenhouse gas emissions. However, when taking all stages of the food system into account (i.e., from production, to transport, to retail, to consumption), the food system is responsible for one-third of all global greenhouse gas emissions. Not only that—the global food system uses about 70% of global freshwater supplies, takes up nearly half of all habitable (ice-free) land surface, is a leading contributor to biodiversity loss, and contributes greatly to fertiliser overuse.

Despite the fact that the food system will always have some impact on the environment (after all, we do need to eat), there are ways to eat in a less environmentally intensive and more sustainable manner. But dietary change needs to happen pretty quickly, and on a large scale, if we are to prevent climate and environmental breakdown.

The various stages involved in the food system. Each stage impacts the environment. Image source: Cucurachi et al. (2022). Image is licensed under Creative Commons License.

There are various examples of what a sustainable diet looks like, but generally speaking, sustainable diets are commonly higher in plant foods, and lower in animal foods, than the typical Irish, European, or North American diet. This is because animal foods tend to have a greater environmental impact than plant foods and, of all animal foods, ruminant meats like beef and lamb and some dairy foods stand out as particularly environmentally intensive. In fact, red meat and dairy production alone accounted for about 57% of agricultural greenhouse gas emissions in 2020. This is because cows release a potent greenhouse gas called methane when they burp, and when forests are cleared for pasture, or to grow livestock feed, there is then less capacity to remove carbon dioxide from the atmosphere. Therefore, to reduce the environmental impact of the diet, a reduction in red meat intake is often the first call of action.

Greenhouse gas emissions of various foods. Image source: Our World in Data. Image is licensed under Creative Commons License.

But when it comes to eating a sustainable diet, it’s much more interesting to think about what you are adding to the diet, not what you are taking from it. Sustainable diets are rich in healthy plant foods like fruits and vegetables, plant protein sources like beans and lentils, and healthy sources of fats (e.g., nuts, seeds, olive oil). This is why sustainable diets are often called sustainable healthy diets, and it is estimated that about 11 million deaths could be prevented each year if everyone shifted to such a diet. However, because there is no one-size-fits-all version of a sustainable diet, sustainable diets can (and should) be tailored based on individual and cultural preferences.

Canada’s food guide is a nice example of what a sustainable diet may look like. Source: © All rights reserved. Canada’s food guide. 2019. Reproduced with the permission from Health Canada (2024). Available at the following address: https://food-guide.canada.ca/en/ 

If you are interested in eating a sustainable and healthy diet, here are some of my top tips:

• Eat meat (and particularly red meat) less often, and replace it with plant proteins like beans, lentils, tofu, and falafel.
• Incorporate fruits like bananas and apples as snacks, as these are easy and convenient to pack in your bag for college or work.
• Swap white bread, pasta, and rice for their brown (whole grain) equivalents.
• Make a shopping list and meal prep for the week ahead, as this will help you to stick to a healthier, more sustainable diet, and will help you to reduce food waste.
• Seek out support from others!

With regards to the last point (and if you are a University College Dublin (UCD), Belfield Campus, student aged 18–30 years), why not join the UCD PLAN’EAT Living Lab? We are a group of researchers from the UCD Institute of Food and Health dedicated to promoting sustainable and healthy diets in UCD. As a collective of researchers, we are working with various stakeholders on campus, including students, to turn our aim into reality.

As part of our work, we will be offering personalised dietary support to students who are a part of our UCD PLAN’EAT Living Lab community. In addition, we want students to be active participants in our work, helping us to develop solutions to make the campus food environment more healthy and sustainable. If you are eligible and interested, you can sign up and join our community here. And if you are interested in finding out more about the many benefits of signing up, check out our previous article on UTOPIA The Edit or visit our Instagram page. Alternatively, feel free to drop me an email at patrick.elliott@ucdconnect.ie with any questions or queries you may have.

That’s all from me, thanks so much for reading!

Patrick Elliott, PhD student on the UCD PLAN’EAT Project