The worthlessness of vitamin D is mildly exaggerated
The article argues that while extreme claims about vitamin D's benefits are often exaggerated, complete dismissal of its importance is also unwarranted, suggesting a more balanced view that acknowledges both the limitations of current research and the potential value of maintaining adequate vitamin D levels.
Background
- The article pushes back against a recent trend dismissing vitamin D as useless. Many readers have seen headlines claiming large trials "prove" vitamin D supplements do nothing for health.
- Vitamin D is produced by skin exposed to sunlight and found in some foods; deficiency is linked to bone problems (rickets, osteomalacia) and has been associated with many other diseases, though causality is debated.
- The "vitamin D skepticism" trend stems from several large randomized controlled trials (e.g., VITAL, D2d) that found little to no benefit from supplementation for the general population. These studies are often cited as definitive proof that supplements are worthless.
- The author's main point: those trials tested low doses (typically 400-2000 IU/day) on people who were already sufficient. This does not disprove benefit for the deficient, or for certain outcomes, or at higher doses.
- Key context: many nutrition and supplement claims are overturned by large trials (e.g., beta-carotene, vitamin E), making skepticism scientifically reasonable. But extrapolating "no effect in sufficient people with moderate doses" to "vitamin D is worthless for everyone" is a logical overreach.