Lewis Hamilton has urged his fans to go vegan and said he feels like "giving up on everything" due to his concerns about the environment.
The 34-year-old, who is on the verge of winning a sixth Formula One world title, spelt out his feelings about the state of the world in three posts on Instagram.
Hamilton switched to a plant-based diet in 2017 and in September he helped launch a vegan burger restaurant in London.
Hamilton wrote: "Hey world, I hope everyone's enjoying their day. I'm sad right now with the thought of where this world is going.
"Extinction of our race becoming more and more likely as we over use our resources. The world is a messed up place. World leaders either uneducated or don't care about the environment at all.
"Agriculture farming is the largest pullutant (sic) we currently have by over 50 per cent, far more than our travel industry combined. I'm sad to see so many people, even close friends ignore what is happening daily.
"Education is key and we were taught that eating animal products was good for us but we've been lied to for 100s of years.
"It's taken me 32 years to understand the impact I am having on the world and I'm figuring out daily what I can do to play a better part. I want my life to mean something and honestly up until now my life's had no meaning.
"Being a part of the issue is not meaningful. Being part of the solution is and I'm striving to do better.
"I urge you to do some research, find the compassion I know you have within you to recognise what you are contributing to in terms of what you eat which keeps the meat and dairy industry flourishing and therefore deforestation, animal cruelty, our seas and climate decaying on a daily basis.
"Go vegan, it is the only way to truly save our planet today. It can be done so quickly, all you have to do is put your mind to it.
"Honestly I feel like giving up on everything. Shut down completely. Why bother when the world is such a mess and people don't seem to care. I'm going to take a moment away to gather my thoughts. Thank you to those of you who do give a damn about the world."