Debunking 5 Myths About Healthy and Sustainable Diets

Myths about sustainable diets

There are few things more confusing than deciding what the best diet is for both people and the planet. The internet is rife with hyperbolic headlines, oversimplified solutions, and heavily promoted remedies -- all of which stoke division and squash good old common sense. When it comes to food, it's not so simple. And while eating in a way that is healthy and sustainable may be complicated, we can make matters worse for nature if we don’t carefully educate ourselves. Below are five common "myths" about healthy and sustainable diets, often promoted with passion and good intentions. However, the information is ultimately not as straightforward as presented.

Myth 1: Local food production is always more sustainable

This idea has received a lot of attention in recent months, but it's context-dependent. Yes, there are many countries that can grow a majority of their food locally, and in these places, that may be the most environmentally friendly way of producing food. But in some cases, relying on local food production could actually increase greenhouse gas emissions and biodiversity loss.

Many countries still face significant burdens of undernutrition and to address this, they may need to increase overall food consumption. But creating extra supply through increased local food production could be problematic for countries like Indonesia and Madagascar to convert biologically diverse and carbon-rich forests into croplands. For many countries it may be impossible to self-address undernutrition, and protect their forests, and lower their food-related greenhouse gas emissions. And what about countries that are not blessed with rich soils and abundant croplands -- how will local food production help them feed their increasing population?

Local food production is the right answer when and where it makes sense. But the fact remains -- feeding everyone on the planet will require an interconnected and interdependent global food system.

"Eating meat is not the problem. The real problem is the overconsumption of meat, heavily processed foods, and refined sugars in our diets, and the underconsumption of fruits, vegetables, nuts, and legumes."

WWF: Planet-Based Diets - Good for us, good for nature!, Oct 8, 2020.



Myth 2: We should all stop eating meat

Eating meat is not the problem. The real problem is the overconsumption of meat, heavily processed foods, and refined sugars in our diets, and the underconsumption of fruits, vegetables, nuts, and legumes. There is ample scientific evidence that shows eating more fruits, vegetables, and other plant foods leads to positive health outcomes.

Meat is not bad for you if consumed in the right proportions, but too much can increase the risk of heart disease, cancer, and diabetes. So, go ahead and have a little bit of meat but don't make it the center of your diet. We all have a responsibility to eat in a way that is good for our planet and our health, but it's time that we stop vilifying certain foods. The science is clear on how we can continue enjoying meat as part of a healthy, sustainable diet.

"Certain methods of livestock production -- sustainably grazing cattle, for example -- can make a positive impact on the environment."

Myth 3: Meat production is always bad for the planet 

It's true that the production of meat, dairy, and seafood contributes significantly to habitat loss, greenhouse gas emissions, and water use. The impact of meat production is compounded because it doesn't just take resources to raise the animals themselves -- beef, pork, lamb, and poultry alike -- but also to produce their feed. Therefore, we certainly need to pay close attention to the worrying trend of increasing global meat consumption.

However, all production isn't problematic. Certain methods of livestock production -- sustainably grazing cattle, for example -- can make a positive impact on the environment. Research shows that cattle raised on well-managed, naturally occurring grasslands (as opposed to deforested land) can increase the amount of carbon stored in the ground and contribute to a biologically rich grassland ecosystem. When integrated into croplands, livestock naturally fertilizes the land, reducing the need for synthetic fertilizers. Food produced in harmony with a healthy ecosystem is a real "win-win."

Due to the volume of beef and other meat products currently being consumed, it is not possible to produce such quantities from well-managed, naturally occurring ecosystems alone. This will become even more difficult as the global population rises to nearly 10 billion people by 2050. We need to learn to balance our meat consumption with the environmental limits of Earth.

Bloomberg: How To Feed 10 Billion People, July 29, 2019.

Myth 4: Don't eat that mango -- it was shipped from overseas!

This is another case of "it's not so simple." People often avoid eating foods from other countries under the assumption that shipping increases the product's carbon footprint. When in fact, transport emissions from food are on average less than 10% of the total global emissions. For the typical American household, only about 5% of food emissions are from transport. This is not to say that these emissions aren't important -- they are -- and the shipping industry is in need of decarbonization. But if you are trying to reduce your total climate impact, avoiding a mango after driving your car to the store doesn't make good climate sense. So, go ahead...make a nice, yummy mango smoothie. Just make sure you walk or bike to the store instead.

"No matter how large or small, every sector needs to reduce its current emissions and avoid any future increases if there's to be any chance of solving the climate crises."

Myth 5: If I travel by air less, I can eat as much meat as I want

Sectors are often pitted against each other to justify certain types of behavior. For example, both livestock production and airline travel contribute to climate change with livestock being responsible for 10 to 15% of global emissions and airline travel for 2 to 3%. Cows emit methane, which is a more potent but shorter-lived gas, while carbon dioxide emissions from planes stay in the atmosphere for several centuries, making a comparison difficult.

Although current emissions from both sectors are already too high, each is projected to dramatically increase its emissions in the future as more people travel and eat meat. No matter how large or small, every sector needs to reduce its current emissions and avoid any future increases if there's to be any chance of solving the climate crises. Calling out one sector as "worse" than another only delays action and increases the risk of irreversible and catastrophic climate change. So no, you shouldn't "flight shame" or skip that next vacation and then eat as much meat as you want. This is a Both/And situation, not an Either/Or.

Yes, eating a healthy and sustainable diet can be complicated, but beware of believing everything that you hear, and be careful not to justify lifestyle choices on faulty information. A little research from credible sources and some critical thinking will ensure your good intentions help fight climate change and save biodiversity.

To learn more, please check out the Planet-Based Diets approach and see how eating different foods will change your environmental food-print.