Two articles on PainSci cite Heaney 2008: 1. The Complete Guide to Trigger Points & Myofascial Pain 2. Vitamin D for Pain
PainSci notes on Heaney 2008:
How much Vitamin D supplementation is enough? How much is too much? “The input needed for efficacy, in addition to typical food and cutaneous inputs, will usually be 1000-2000 IU/day” and “toxicity is associated only with excessive supplemental intake (usually well above 20,000 IU/day).” This paragraph from the article on toxicity and safety is particularly relevant:
Both the intoxication literature and the recent controlled dosing studies have been reanalyzed by Hathcock et al. These authors show that essentially no cases of confirmed intoxication have been reported at serum 25(OH)D levels below 500 nmol/L. Correspondingly, the oral intakes needed to produce such levels are in excess of 20,000 IU/day in otherwise healthy adults and, more usually, above 50,000 IU/day. These findings led Hathcock et al to select 10,000 IU/day as the tolerable upper intake level (TUIL, or UL), with considerable confidence. It is likely that a higher intake could be defended, but little good would be served by doing so, as 10,000 IU/day is substantially more than is apparently needed for any recognized efficacy endpoint.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
The functional status indicator for vitamin D, for both safety and efficacy, is serum 25-hydroxyvitamin D concentration. Efficacy for several health endpoints requires levels of 80 nmol/L or higher. Toxicity occurs at levels of 500 nmol/L or higher. The input needed for efficacy, in addition to typical food and cutaneous inputs, will usually be 1000-2000 IU/day of supplemental cholecalciferol. Toxicity is associated only with excessive supplemental intake (usually well above 20,000 IU/day).
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- No long-term effects after a three-week open-label placebo treatment for chronic low back pain: a three-year follow-up of a randomized controlled trial. Kleine-Borgmann 2022 Pain.
- Exercise and education versus saline injections for knee osteoarthritis: a randomised controlled equivalence trial. Bandak 2022 Ann Rheum Dis.
- Association of Lumbar MRI Findings with Current and Future Back Pain in a Population-based Cohort Study. Kasch 2022 Spine (Phila Pa 1976).
- A double-blinded randomised controlled study of the value of sequential intravenous and oral magnesium therapy in patients with chronic low back pain with a neuropathic component. Yousef 2013 Anaesthesia.
- Is Neck Posture Subgroup in Late Adolescence a Risk Factor for Persistent Neck Pain in Young Adults? A Prospective Study. Richards 2021 Phys Ther.