The livestock industry is a global sustainability crisis that many overlook, according to a start-up focused on tackling climate change and global food insecurity.

"I think when we talk about urgent, the most pressing global crisis when it comes to sustainability, [the] livestock industry is most probably the most overlooked industry that people do not know about," David Yeung, founder of Green Monday told CNBC on Thursday.

The ability to continue feeding the current population of more than 7 billion people is already proving to be an issue, and that total is only projected to grow (it's expected to reach 9 billion to 10 billion in the near future), Yeung said. Add the need to feed any livestock that humans are raising, and the crisis becomes all the more challenging, he said.

"But what people don't know, is that we have 2 billion pigs, close to 2 billion cows, and over 20 billion chickens on this planet," Yeung said, explaining that the industry consumes a disproportionate amount of land and water.

The environmental advocate told CNBC the livestock industry is a problem because of its release of carbon into the environment, challenges with food production efficiency, and connection to water scarcity. That all serves as the "biggest and most overlooked" issue that people are unaware of related to sustainability, he said.

One of the steps that the start-up has taken to resolve the problem is to partner with innovative food-tech companies to create alternate vegan food choices.

"Plant-based food tech companies have been absolutely exploding," Yeung said, adding that Green Monday has partnered with Beyond Meat to bring its products to Asia.

Beyond Meat is a plant-based food company that has received funding from actor Leonardo DiCaprio and Microsoft founder Bill Gates.

The Los Angeles-based producer sells the Beyond Burger, a meat-free patty that imitates the look and taste of a meat patty.