Reese Witherspoon Lands 5-Year Beauty Deal with Biossance After Getting Serious About Clean Beauty

Reese Witherspoon finds her favorite beauty products just like the rest of us: by browsing the aisles at Sephora. That's how the actress and entrepreneur fell in love with Biossance skincare — and now she's the global ambassador for the clean, sustainable beauty brand.

"I've been really curious about clean beauty for quite some time, but didn't do the work and research," Witherspoon tells PEOPLE. "I obviously had more time over the past year, and I noticed Biossance at Sephora over the holidays and started using the products. I was blown away by not only how effective they were, but also the sustainability and science built into the brand's skincare line."

To her delight, the Hello Sunshine founder, who has built an empire around female empowerment, advocacy and community, also found the people behind the brand to align with her values.

"They have female scientists working on the products and they're very open about everything they develop and the ingredients," she shares. "It's a very transparent, socially conscious business, and I love that it's female led."

For the team at Biossance, tapping Witherspoon as part of a five-year partnership was kismet.

"Clean beauty really centers around the concept of empowerment and education," Biossance president Catherine Gore tells PEOPLE. "And Reese has always authentically championed both those things. In addition to that, she always adds an air of relatability and just has this genuine zest and curiosity for life that we were very much drawn to. We're just so honored and so proud that we're able to partner with Reese on this exciting five-year project."

We caught up with Witherspoon to learn more about her go-to products, her approach to aging and what makes her feel most beautiful.

PEOPLE: How did spending more time at home over this past year make you take stock in your skincare routine?

Witherspoon: I was wearing so much less makeup, and I really just focused in on my skin. I feel like we were all thinking about our skin a lot, because we were all in Zoom meetings and on FaceTime. It gave me a little time to really actually invest in my natural curiosity of, 'What is clean beauty?' and to find products that are science-based, innovative, well-made and light on the skin. Nobody wants to feel bogged down by heavy creams and smells and lotions and what I love about the Biossance collection is it's such a light, easy to wear product range.

What Biossance product is top of your rotation right now?

Witherspoon: I love the Squalane + Vitamin C Rose Oil. It's great for travel. It's light. I'm traveling and working again, and so it's so nice to take on airplanes and it helped me through the winter with the dry skin and also the Omega cream. It's really moisturizing, it's really smoothing, and it also, it just isn't greasy. So, I can apply it a couple of times a day and it just feels… It's not heavily perfumed as well. I'm really sensitive to smells, and so that's one thing that can really put me off products and this is just so light and I just, I was blown away by how effective it all was considering how clean it is, as well.

How has your beauty philosophy evolved?

Witherspoon: I'm 45 now. My skin has totally changed. Pregnancy really changed my skin. I have some darker spots. The Vitamin C products have been really helpful brightening those darker spots and the pigmentation. I just try to be really good about taking care of my skin twice a day. I really invest that time in the morning and at night, especially on my neck and my hands. We all know those signs of aging , but it's really about, 'How do I feel?' Not about how it's perceived but, "How am I'm taking care of myself?' And I think when you talk about using products that are good for your skin, your largest organ, you are making that investment in yourself.

What's your earliest memory of beauty?

Witherspoon: I spent a lot of time with my grandmother, because my mom was working a lot. I remember being a little girl and looking up at her and just thinking she was the most beautiful woman in the world. She had beautiful wrinkles and she had expression, but she also invested time in herself and her appearance because she would always say to me, 'When you look good, you feel good.' I really took a lot of tips from her.

As someone who is not only photographed on the red carpet but filming a TV show, do you feel pressure to look a certain way?

Witherspoon: I was so lucky to have women in my life who loved aging and getting older — and saw that it wasn't a setback. It was actually a great thing to be a wise older woman and to grow older gracefully. As women, we're hard on ourselves, and we can be very self-critical. It starts with how you see your mother feel about herself and your grandmother feel about herself and your sisters. I think it's really important to focus on positive messaging about being the best version of yourself that you can possibly be. And a lot of that is investing in yourself and really carving out some time to care for your skin. It is important.

When do you feel the most beautiful?

Witherspoon: When I'm around my husband and my kids and just being at home and feeling like there's no pressure to look a certain way. When I'm happy, having fun and goofing around. I spend lot of time outside in nature. That always makes me feel so much more connected to the world and connected to who I am as a person. So, I would definitely say that my outdoor self feels like my most naturally beautiful self.