Each year on April 22nd, people around the world celebrate Earth Day. Many of us are inspired to volunteer for ocean cleanups, start biking to work, change our light bulbs and take shorter showers. All of those efforts are profoundly needed and worthwhile, yet more and more people are realizing that perhaps the most impactful action we can take as individuals to protect and heal the planet is committing to eat less meat.

The impacts of animal agriculture on the environment are not insignificant. The United Nations' Food and Agriculture Organization has stated, "the livestock sector is a major stressor on many ecosystems and on the planet as a whole. Globally it is one of the largest sources of greenhouse gases and one of the leading causal factors in the loss of biodiversity, while in developed and emerging countries it is perhaps the leading source of water pollution."

Recent investigations revealed that some farms in the United States have resorted to spraying excess waste into the air, only to have it rain down on neighbouring low-income communities.

Sound economics and science confirm what common sense tells us: that we can feed more people using far less resources if we eat more plant-based foods, rather than using valuable crop land, water, fertilizer and fuel to grow plants destined for farm animals' feeding troughs.

The most impactful action we can take as individuals to protect and heal the planet is committing to eat less meat.

Numbers don't lie: every second of every day, over 2,400 land animals are killed for food. To add insult to injury, animal agriculture is one of the most significant contributors to climate change.

Around the world, these animals are intensively confined in factory farm conditions where they will never experience even the most basic of comforts such as feeling sun on their backs or breathing fresh air. After short lives of misery, they are crammed into transport trucks and taken to rushed, under-regulated and over-burdened industrial slaughterhouses.

From land to sea, overfishing is causing tremendous stress on the ecosystem. An estimated one trillion to three trillion fish per year, and the raising of billions more on fish farms -- often plagued by diseases that further threaten wild fish -- is rapidly leading us toward a world of empty oceans.

Cutting back on meat not only benefits the environment and countless animals, but our own health also improves when we eat more plant-based meals. According to the Johns Hopkins Bloomberg School of Public Health, an active proponent of Meatless Mondays, current levels of meat consumption have been shown to increase risks of heart disease, type 2 diabetes and certain cancers.

This has given rise to a booming plant-based food movement; meat- and dairy-free meals have never been so delicious. These days you'd be hard-pressed to find a restaurant that doesn't offer at least one tasty veggie option (which is usually easier on your wallet than the meat-based selections).

So this Earth Day, take the time to visit a park, forest or beach, and soak in the natural beauty the planet has to offer. While you're there, remember that preserving and restoring these fragile ecosystems for future generations depends on us all reaching for smarter food options.

Humane Society International advocates the Three R's of eating with a conscience: refining our dietary choices by switching to products that meet high animal welfare standards; reducing our consumption of animal products; and replacing animal products in the diet with plant-based options.

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