Environmental impact of plant-based diets

Written by: Sarah Glinski, RD

There is no doubt that sustainability is a hot topic. In fact, a recent report showed that while most Canadians look to the federal government for leadership on climate change, 42% to 57% of people polled believe the government is not doing enough to fight climate change.¹ From forgoing fast fashion, to recycling, to composting, people are looking for ways to reduce their personal environmental footprints. Sustainable diets are another key area in which people are looking to make changes to benefit the environment. As dietitians, we are in a unique position to help our clients make an impact not only on their own health, but on the health of the planet.

WHAT IS A SUSTAINABLE DIET?

What exactly is a sustainable diet? The definition of sustainable diets from the Food and Agriculture Organization of the United Nations dating back 10 years still holds true as “… those diets with low environmental impacts that contribute to food and nutrition security and to healthy life for present and future generations. Sustainable diets are protective and respectful of biodiversity and ecosystems, culturally acceptable, accessible, economically fair and affordable; nutritionally adequate, safe and healthy; while optimizing natural and human resources.”²

THE ENVIRONMENTAL IMPACT OF HUMAN DIETS

It is well known that raising livestock for human consumption requires many inputs (such as water, land, and feed), and produces undesirable by-products that are harmful to the environment.³ A study from Australia found that livestock farming was the largest greenhouse gas producer among agricultural sectors, with 70% of greenhouse gas emissions coming from livestock farming.⁴ For each kilogram of beef produced compared to the production of each kilogram of rice or potatoes, beef production requires⁵:

Another study⁶ showed that, compared with dairy butter, certain plant-based margarines and spreads:

A systematic review of the environmental effects of vegetarian and omnivorous diets found it may be possible to achieve the same environmental impact as a vegan diet without completely excluding meat and dairy, but rather by substantially reducing the intake of these foods.³ Accordingly, following a plant-based diet for environmental reasons does not have to be all-or-nothing. This is an important message to share with our clients, as it may provide encouragement that generally following a plant-based diet is something that can have profound positive effects on our environment.

HOW DOES A PLANT-BASED DIET IMPACT THE ENVIRONMENT?

PLANT-BASED DIETS AND HEALTH

Contrary to popular belief, a plant-based diet is not necessarily a vegan diet. While the two share characteristics, they differ in one fundamental way – plant-based diets can still include the consumption of animal-based products. Rather than focusing on foods to EXCLUDE, people following plant-based diets focus on all the wonderful plant-based foods they can ADD to their diet.

Plant-based diets are not just good for the environment – they may also be good for overall health. A study¹¹ found that increasing fruit and vegetable consumption by 200 grams per day was associated with:

Another study found that following a plant-based diet may be effective to promote diverse and beneficial gut microbiota that support overall health.¹² The effect of unsaturated plant-based fats on heart health has been an area of study for over 50 years, with studies showing that replacing saturated fats with unsaturated fats is associated with lower LDL cholesterol , as well as lower overall incidence of cardiovascular disease.¹³ Finally, plant-based diets have also been shown to be beneficial in the prevention and treatment of type 2 diabetes.^{14 15 16}

Whether a person decides to cut out animal products completely, or if they are simply looking to reduce the amount of animal products they consume, shifting towards a plant-based diet is an important change they can make towards a more sustainable lifestyle.

For tips on how your clients can get started with plant-based eating, plus strategies for living a more sustainable lifestyle, check out our guide, “Getting Started with Sustainable Eating.”