![Stubborn Vitamin D Levels? Reviewers Swear By This To Reach Sufficiency Stubborn Vitamin D Levels? Reviewers Swear By This To Reach Sufficiency](https://mindbodygreen-res.cloudinary.com/image/upload/c_crop,x_0,y_0,w_2000,h_1333/c_fill,w_2000,h_1200,g_auto,fl_lossy,f_jpg/org/qglhc387nk6l0ecl8.jpg)
Most U.S. adults fail to consume even small amounts of vitamin D on a daily basis – 93%1 to 100% by some estimates. Unsurprisingly, considering these staggering stats, many Americans are living with suboptimal vitamin D levels: 41% of U.S. adults2 are insufficient, and a whopping 29%2 are straight-up deficient.