While winter is filled with many beautiful and joyous things (like holiday celebrations, glistening snow, and winter sports like skiing and ice skating), it’s also freaking cold and annoyingly dark by 4 p.m. While making a conscious effort to expose your eyes to natural sunlight early in the morning and later in the afternoon can help modulate your circadian rhythm and support serotonin production, according to a 2021 scientific review, vitamin D is also key, playing a direct role in the synthesis of both melatonin (the “hormone of darkness”) and serotonin1. Despite how critical it is, 29% of U.S. adults2 are deficient in vitamin D, while another 41% are insufficient. With 70% of American adults missing the mark on vitamin D sufficiency, it’s no wonder so many people deal with the winter blues! Taking a high-quality vitamin D supplement, like mindbodygreen’s vitamin D3 potency+, every day is an easy way to help you achieve and sustain sufficient vitamin D levels (and support a healthy mood!) year-round—but especially during the cold, dark months of winter.* With 5,000 IU of sustainably sourced D3 and built-in organic fats for optimized bioavailability, vitamin D3 potency+ delivers the healthy vitamin D levels your brain craves to truly make this season the most wonderful time of the year!*