Harley Quinn Smith made her big-screen debut at the tender age of one, in dad Kevin Smith's cult flick, Jay and Silent Bob Strike Back. These days, though, the 20-year-old vegan actress is paving her own way with star-making performances opposite Molly Ringwald in All These Small Things and Quentin Tarantino's star-studded blockbuster Once Upon a Time in Hollywood, alongside Brad Pitt, Margot  Robbie, and Leonardo DiCaprio.

We recently sat down with the up-and-coming actress – who co-stars with her dad in Jay and Silent Bob Reboot – to talk about what prompted her decision to go vegan, her favorite guilty pleasure and the real reason why she insisted her dad to stop eating flank steaks and start eating falafel. He subsequently lost 40 pounds, thanks to his new diet.

What made you decide to adopt a plant-based lifestyle?

Harley Quinn Smith: There were definitely a lot of factors, the main one being my rabbit. When I adopted her, she was in really terrible condition. She had all of these stitches and a ripped ear and she was covered in pee. Before she was brought to the shelter, she had lived in a house of hoarders. They had 100 other rabbits, so she had a really terrible life. She was totally scared of humans. After I adopted her, she was just standoffish and scared and didn't know if she could trust me for two or three months.

It just broke my heart. Then after months and months of showing her that I wanted to give her love and would never hurt her, she finally became this loving creature. It was so incredible to see her go from being so traumatized to wanting love and affection. Her transition was the thing that made me take a step back and realize, “This is what human compassion can do to an animal's life. If you witness that first-hand then you're a hypocrite if you continue to eat animal products.”

What challenges did you face when you first stopped eating meat?

HQS: First I went vegetarian, then a year later I went vegan. I think I encountered the same problems that everybody has. It's a huge change and kind of daunting at first. I would say the hardest part was realizing what I had been doing eating meat, and taking responsibility for my actions. I didn't miss anything, but it was really hard to come to the realization that I had been contributing to the meat and dairy industry for my entire life. That was really hard, just coming to terms with the truth and reality of the life that farmed animals have.

Was it ever awkward in social settings like family get-togethers or birthday parties?

HQS: It's definitely hard to watch other people you love eating meat. But, at the end of the day, it's their life. I'm never going to force anybody to think the way that I think or to be vegan. Even if it is uncomfortable watching other people eat meat,  I'm never going to push that on somebody because that's not the right way to make a change.

Your dad Kevin Smith became vegan last year. Did your healthy lifestyle influence his decision?

HQS: He had a heart attack about a year ago. It was a serious situation. After that happened, I made it very clear to him that he had to go vegan. That wasn’t so much advice, as it was, ‘You have to do this.’ I didn’t really give him a choice. [In the year since he lost 50 pounds and got healthier, thanks to eating a plant-based diet.]

I don't think he understood why at first, but he trusted me. It's actually kind of shocking -- all of the amazing things that veganism can do for your health. Now he eats things like falafel and vegetables that he never would have eaten a year ago. Things change and you adapt, because, what else are you going to do? He lost

Is it ever tough sticking to a plant-based diet when you're shooting on sets?

HQS: I'm always fine dealing with it, but also I live in Los Angeles where veganism is acceptable, so it's not really hard. People are usually very accommodating. I'm really thankful because I know it's not like that in other places at all. I feel lucky that I'm definitely in the right place to be vegan. But every vegan has those times where they can't get a meal. You just kind of deal with it. It's not the end of the world.

What are your favorite go-to snacks that you always keep in your handbag?

HQS: I usually always carry some dried fruit in my bag. That's always a really good thing to hold you over. I've been eating a ton of these things called Hippeas, which are vegan cheese puffs. [Sidenote: we at The Beet are addicted.]

Any favorite plant-based recipes you love to make at home? 

HQS: I rarely cook because there is so much vegan food in L.A. it's kind of insane. I definitely should cook more, but it's so easy to just go out and get food that I never really make the time.

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Where are some of your favorite restaurants in L.A.?

HQS: There's this place I've been going to multiple times a week called Jinja. They have the most incredible vegan ramen. My favorite restaurant is this place called My Vegan Bowl. They have everything from tacos to chow mein.

What did you eat for breakfast today?

HQS: I always have a smoothie because it makes me feel good to start my day with some fruit and vegan protein powder. I always get this smoothie called Blueberry Bliss with blueberries, bananas, vegan protein powder and granola from Urth Bar. I can't get anything else because it's become so ingrained in my routine.

How do you make sure you're getting enough protein in your diet?

HQS: I eat a ton of beans all of the time. That's my favorite source of protein. I love vegan meat, but beans are just so accessible. Honestly, I've never had a problem. I'm always incredibly surprised when non-vegans ask vegans where they get their protein because there are so many options outside of animal products.

Do you enjoy faux meat products like the Impossible and Beyond Burger?

HQS: Yeah, for sure. I love Beyond Burgers. And Burger King has the Impossible Burger, which is just insane. These options are becoming so much more accessible and normalized. If somewhere like Burger King has the Impossible Burger, there's really no excuse not to be vegan now!

Why do you think plant-based diets have recently become so mainstream?

HSQ: I think we're living in a more compassionate time. Obviously, there are still a plethora of issues, but younger people especially -- people my age – are not afraid to be compassionate. Part of that entails making the connection that eating animal products isn't a compassionate thing to do. I think my generation is much more open and accepting as human beings.

Do you have a favorite guilty pleasure or sweet treat?

HQS: By far, my favorite food is vegan pizza. There's this place called Mohawk Bend in L.A. that has this cheese pizza that is my favorite food in the world. Anytime I want to indulge, it's always going to be pizza.

What would you tell others who are considering making this lifestyle change?

HQS: Coming to terms with the reality of the animal agriculture industry is very hard, but it's really important that you take responsibility for your actions. It's hard to accept but it's also extremely vital that everybody does take responsibility for themselves. We're living in a time where our land is literally on fire. Something absolutely has to change soon.

If you care about the future of our planet – and what this world is going to look like in 30 years – you should be taking responsibility for your actions. It's a beautiful way of living, knowing that you aren't contributing to the pain and suffering of animals. That ultimately makes you a happier person. Your physical health will affect your mental health and vice versa. Truly, going vegan improves absolutely everything. There absolutely isn't a downside.