in Las Vegas, shared which holy grail product turns back time with The U.S. Sun.
"Retinol is a true anti-aging powerhouse," Dr. Costa told The U.S. Sun.
"It stimulates collagen production, improves skin texture, enhances skin firmness, and reduces fine lines, wrinkles, and sun damage," he added.
"Retinol also accelerates cell turnover which promotes the shedding of dead skin cells to reveal more healthy, glowing, youthful skin."
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The find is described as being able to combat the signs of aging and dryness while targeting uneven skin tone.
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TURNED OFF TIKTOK TRENDS
Another one of Dr. Costas' skincare commandments includes not being fooled by TikTok fads - especially hyaluron pens.
"These are essentially off-brand, unregulated fillers being administered by unqualified people," he said.
"These are extremely dangerous and can cause infection and vascular issues if the product gets into the bloodstream and even blindness."
FORGET FLASHY
Dr. Costa explained how not all skincare products are worth the price — and wants you to take advice from the experts, not the stars.
"I think there's a ton of expensive skincare product lines with fancy marketing and celebrity endorsements that often lack substantial scientific evidence to justify their high price tags," he said.
He advises being wary of "eye-catching packaging" and "false promises."
"Medical-grade skincare which has been backed by scientific studies and research generally delivers much more high-quality results," he said.
He emphasizes spending money on only those products with clinically proven ingredients.
You can also ask for individualized treatment recommendations from medical professionals.
Dr. Costa previously spoke with The U.S. Sun about his tips for preventing wrinkles.
He says the most common mistake you're making is neglecting your skin until you're older.
"Sunscreen is the best preventative way to preserve aging because sun damage is the leading cause of wrinkles and hyperpigmentation," he said.