The Interface Between Climate and Diet

November 28, 2020


What Causes Climate Change?

The main contributing factor to climate change is the greenhouse effect. Greenhouse gases (GHGs) insulate our climate and maintain a stable surface temperate on Earth. GHGs include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), ozone and water vapour (H2O). These GHGs trap heat in our atmosphere and raise global temperatures.

Does Diet Make a Difference?

Yes! According to a 2018 article in the journal Science, one-quarter of the human-derived GHGs come from the world’s food system. This happens in a number of ways:

  1. Clearing land for industrial farming and livestock releases carbon stores into the atmosphere.
  2. Animals release methane gas when they digest their food. Methane is about 30x more efficient than carbon dioxide at trapping heat in our atmosphere.
  3. Fossil fuels are used to operate farming equipment, make fertilizer, and ship and store produce throughout the globe.

Yikes! What Can We Do About Climate Change?

Our power lies in our daily choices and actions. Many of these daily choices and actions reside in the food we eat. Here are a few tips to help you make healthy choices to benefit the Earth as well as your own health and wellness:

  1. Eat plant-based and support regenerative farmers
  2. Eat local
  3. Eat organic
  4. Eat real food
  5. Eat only what you need


1. Eat Plant-based and Support Regenerative Farmers 

It takes more land, energy and water to produce a pound of animal meat than it does for a pound of plant-based protein. Dairy also has a large carbon footprint compared to plant-based food, and the extent depends on the type. A 2018 study in the journal Science found that mozzarella and cheddar cheese have a significantly larger footprint than milk, yogurt and soft cheeses.

When discussing milk options, we must also consider the environmental impact of water use. Lets look at the different types of milk discussed in the 2018 study:

  • 1L cow’s milk requires 628L water
  • 1L Almond milk requires 371L water
  • 1L Oat milk requires 48L water

According to the above data, almond milk requires approximately half the amount of water required to make cow’s milk. However, almond milk requires approximately 7x more water than the amount required to make oat milk. Out of these three options, oat milk would be the most sustainable choice. Well, actually, water would be the most sustainable choice. 🙂

What if I can’t give up meat and dairy?

The best ways to eat meat responsibly is by reducing your intake and choosing more sustainable and humane meat options. Try following the Meatless Mondays movement and educate yourself on the environmental impact of different animals raised for consumption. According to a 2018 study in the journal Science, the biggest contributors to GHGs are beef and lamb, followed by farmed crustaceans, cheese, pork, farmed fish, poultry and eggs (in order of most to least GHG emissions). Therefor, choosing chicken over beef, or wild fish over lamb, would be better choices for the environment.

You can also support local organic, free-range and regenerative farmers. Here are a few sources you can find in the Greater Vancouver area:

Meatme delivers pastured meats from local regenerative BC farmers.

Pasture to Plate on Commercial drive sells organic and grass-fed meat.

Two Rivers Specialty Meats in North Vancouver sell organic and locally sourced meat.

EcoDairy offer organic and fresh dairy products from free-run cows in Abbotsford.

2. Eat Local

The carbon footprint caused by the transportation of food depends on the type of transportation. For example, produce shipped by plane has a much higher footprint than when shipped by sea. Typically, more perishable food items, like berries, are shipped by plane to reach stores faster. Whereas, shelf-stable produce, like apples and oranges, are shipped by sea.

To limit transportation further, you can buy from your local farmer’s markets. You can find farmer’s markets within the Greater Vancouver area at Eat Local or

Or better yet, you can grow your own food! There are many ways to get creative if you live in an urban setting with little land available. Here are a few suggestions to try:

  1. Grow veggies and herbs in planter boxes and/or hangers on your patio or window-sill
  2. Consider vertical planters to conserve space
  3. Create your own mini greenhouse indoors with grow lights
  4. Make your own worm composting bin
  5. Join a community garden

3. Eat Organic

The use of pesticides can put your own health and the soil at risk. According to a study in the journal Archives of Agronomy and Soil Science, long-term application of pesticides can lead to a loss or change in beneficial soil microflora. A change in soil biodiversity can affect nutrient turnover, carbon sequestration and GHG emissions from soil.

What if I can’t afford to eat organic?

According to the Environmental Working Group’s (EWG) 2020 Shopper’s Guide to Pesticides in Produce, there are 15 fruits and vegetables that a have low risk of pesticide exposure called the Clean Fifteen. The EWG’s 2020 Shopper’s Guide also lists 12 fruits and vegetables that have a higher risk of pesticide exposure called the Dirty Dozen, these should be grown and purchased organically. 

4. Eat Real Food

This is a big one when it comes to your health and the health of the Earth. Processed food requires more fossil fuels for processing and transportation, and comes with chemicals and packaging that can pollute the Earth.

Processed food often contains refined sugar, sodium and artificial ingredients that negatively impact your health. One study found that a 10% increase in processed food over a 5 year period was associated with a 12% higher risk of cancer. Processed food has also been associated with an increase risk of obesity, heart disease, high blood pressure and diabetes.

Tips for choosing real food:

  1. Check labels. If you can’t pronounce it, don’t eat it.
  2. Shop the outside aisles in the grocery store, this is typically where you’ll find fresh produce.
  3. Cook more meals at home so you’re not tempted to grab food on-the-go.
  4. Choose food that comes from the Earth. Whole grains, fruits, vegetables, legumes, nuts and seeds come straight from the Earth and have all the vitamins and minerals your body needs without all the chemicals and packaging, especially when buying organic and local.

5. Eat Only What You Need

According to WRW Canada, an alarming 58% of food produced in Canada is lost or wasted each year, that’s 35.5 million tonnes of food per year. Considering what I’ve discussed regarding the energy expenditure, water use and GHG emissions associated with food production, this is extremely wasteful.  Here are some ways you can reduce your own food waste:

  1. Don’t go grocery shopping when you’re hungry
  2. Plan your meals at least 3 days ahead so you know exactly what you need
  3. Don’t order more food than you need in restaurants. If you do, take the leftovers home and eat them later.
  4. Be lenient with the “sell by” dates on labels. These dates usually represent peak quality and not spoilage.
  5. Compost your leftovers. When food is thrown out, it can release methane gas into the atmosphere as it decomposes in the landfill. 

In Summary

Our daily choices can have a large impact on our environment and our health. Here is a summary of suggestions that can be used as a guideline to support your health and the health of mother earth.

  1. Choose sustainable plant-based options
  2. Reduce your meat intake
  3. Support local regenerative farmers
  4. Choose organic and local produce when able
  5. Grow your own food
  6. Eat food that comes straight from the Earth (limit processed food)
  7. Compost your leftovers 
  8. Be strategic with your grocery shopping, purchase only what you need
  9. Listen to your body when ordering food, will you be able to finish it?
  10. Make policy changes:


Thanks for reading! Let’s work together for a brighter future for all inhabitants of this beautiful Earth.

In health,

Dr. Fiona