New Guidelines question the routine use of Vitamin D as a supplement : Myths & Facts!
Key Points
2011, the Endocrine Society proposed a definition Vitamin D deficiency as “Deficient” when < 20 ng/mL and “Insufficient” between 20 to 29 ng/mL.
- 2024: Paradigm Shift : recent guidelines (The Journal of Clinical Endocrinology & Metabolism, 2024, NEJM journal watch 2024 )are in sharp contrast to prior opinions from other experts who called vitamin D “the closest we have to a panacea.”
- Now, The Endocrine Society No longer endorses specific vitamin D3 levels to define vitamin D deficiency.” Still most Labs test it as a part of “health packages”. The “deficiency” and “insufficiency” based on serum levels of vit D levels as shown by most labs should be abandoned.
Insufficient clinical data :
- Clinical research has failed to clearly establish distinct thresholds of serum vit D levels which can be held responsible for causing diseases or curing them if supplemented with Vit D3.
- The long-known skeletal benefits of vitamin D and calcium related to rickets or osteoporosis remain valid.
- Extra-skeletal effects on cancer, cardiovascular risk, respiratory effects, autoimmune diseases, diabetes, and mortality were not confirmed by recent, large RCTs. Some favourable trends were seen but not proven yet.
- Metanalysis of clinical studies shows a small, insignificant mortality benefit with empirical vitamin D supplementation but no effect was seen on lowered risks for fractures, falls, or infections ( VITamin D and OmegA-3 TriaL (VITAL).
Who should (NOT) be tested?
- General population: Adults (19–74 years): Neither routine testing nor routine vitamin D supplementation are recommended.
- For older people (age ≥75), routine testing of 25(OH)D levels is not recommended. However , empirical daily supplementation (meaning suggestive but not proven) use “may” decrease mortality and can be taken.
- Routine screening for low vitamin D levels in adults with obesity and those with dark complexion is NOT recommended.
Empirical vitamin D supplementation is recommended
- During pregnancy (through foods or vitamin preparations).
- Adults with “high-risk prediabetes: might retard progression to diabetes.
- Note, however, these guideline do not apply to people with clinical conditions that affect vitamin D physiology (e.g., malabsorption, chronic kidney disease, other disorders of calcium metabolism) or to people with bone symptoms that could reflect osteomalacia caused by vitamin D deficiency. In those cases, testing is obviously necessary.
How to take Vit D supplementation:
- Natural food sources of vitamin D : Fortified cereals/ dairy, Orange juice, butter, Whole milk, Mushrooms, Fish (e.g., herring, mackerel, or tuna), Salmon/ Cod liver oil, etc.
- Need for vitamin D supplementation (and the amount of supplement needed), are dependent on age, weight, skin complexion (dark absorb less sun, hence vit D deficient), location with respect to the world’s equator, time spent outdoors vs indoors, and diet.
- Recommended daily allowance for vitamin D intake (diet / oral supplement) :
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- < 70 years : 600 IU ; > 70 years : 800 IU ; average of ≈1000 IU daily is reasonable
- Daily small doses are better than high bolus doses (weekly or monthly),
- Some evidence of adverse effects with intermittent high dosing.
- Oral administration preferred . Intramuscular injections reserved for special clinical situations (severe gastrointestinal malabsorption syndromes or after bariatric surgery).
Final Comment
These guidelines are a game changer. Motto is “Giveth to those who Needeth”.