"I hope people make the resolution to invest in themselves, both on the inside and outside. Beauty really does come from within, specifically in terms of your health. So, if you're eating well and taking care of your body, it really shows in your hair and skin. You can see the glow. It's a holistic outlook. If you're kind to yourself, choose a healthier lifestyle, and make time for yourself, it shows, and that's what makes people so beautiful.

Also, invest in products that allow you to take care of yourself, and make sure they really work. I love Nutrafol as a hair supplement, and Kerastase Fusio-Dose Homelab, $98 is my favorite because it's customized to each individual's needs and designed for weekly use. It's a great way to take care of your hair and it's quick, which is great when you're making time for yourself in the midst of a busy schedule."

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"I gave up all kinds of sugar years ago and I hope my clients and others will also do it this new year. I gave them up because they cause cross-linking of the collagen fibers in the skin, which leads to brittle collagen and aging, enlarged pores and skin inflammation. They also produce enzymes, which break down collagen and elastin, making skin saggy and prone to wrinkles at a younger age. It's a New Year's resolution I have kept and intend to keep; it's more a lifestyle choice at this point.

Cutting down on sugar intake not only helps with the youthfulness of the skin but the body as well. Sugar also has so many negative effects on the body's system. If you have sugar cravings, remember, it might be thirst or hunger, so drinking water and eating protein will help lessen the craving. If the craving is still there, have a quarter teaspoon of honey or 75 percent to 80 percent dark chocolate. But just remember that sugar is sugar, whether it's table or organic." Instead, indulge your cravings with a nourishing body treatment like Shiffa Sweetness Body Polish, $84.

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"I want people to spend a little more time caring for themselves. Most people put a lot of effort into caring for others and put themselves on the backburner. I think you're a better caretaker when you take care of yourself as well. Since the holiday season is so hectic, our bodies are getting less sleep and we're running around more, so we're depleting ourselves now more than ever.

Develop a five-minute ritual you can do every morning or evening before you go to bed that will make you feel just a little bit more cared for, even if it's five minutes of dry brushing before you get in the shower. Dry brushing before your shower in the morning is a quick ritual that will really enhance your health and well-being all over. Using a nice beauty bar on your body like Ritual Bar, $22, will also help your skin stay healthy all over."

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"In the new year, I'd love for people to stop compromising: we can have both beautiful hair and skin! So many hair products have ingredients that you just wouldn't want to put on your face or skin. But what's on your hair is on your skin — and hair care products can cause breakouts!

People who are prone to breakouts want and need products that won't clog their pores. The American Academy of Dermatology specifically recommends that people who are breakout-prone use products, including hair products, that are non-comedogenic.

My hair care products were a big source of breakouts and, surprisingly, as a Harvard-trained dermatologist, I had not learned much about the connection between hair products and acne. It's why I developed Seen Hair Care, products specifically designed with the health of the skin in mind that are clinically tested to be non-comedogenic and non-irritating."

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"I hope people will begin to nourish their hair health from within. I strongly believe skin and hair health starts internally. I sent clients to the health food store to buy supplements and vitamins for years before I came out with Ouai supplements. The Thinning Hair Supplement, $28, includes ashwagandha extract, which is great at reducing stress levels (a major contributor to hair loss), and niacin to help prevent blockage of cholesterol at the pores. Healthy hair starts at the scalp and if your scalp isn't healthy, then your hair doesn't stand a chance. But a healthy scalp starts from within, which is why hair growth supplements, a healthy diet and exercise are essential for growing out your strands."

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