How long does it take for vitamins to take effect
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How Long Does It Take for Vitamins to Take Effect?
Understanding the timeline for vitamins to take effect can help individuals manage their expectations and better plan their supplementation routines. Research provides insights into the varying timeframes for different vitamins to show noticeable benefits.
Vitamin D and Calcium: Periodontal Health Improvements
Short-Term and Long-Term Effects
A study examining the effects of vitamin D and calcium supplementation on periodontal health found that improvements can be observed over a period of months. Participants taking vitamin D (≥400 IU/day) and calcium (≥1,000 mg/day) showed better periodontal health compared to those not taking supplements. Clinical parameters improved in both groups over time, but the supplement group showed more significant improvements at 6 months (P = 0.034) and 12 months (P = 0.058)1. This suggests that while some benefits may be seen as early as 6 months, more pronounced effects might require up to a year.
Multivitamins: Mood Enhancement
Gradual Improvement Over a Year
Another study focused on the impact of multivitamin supplementation on mood over a year. Participants took either 10 times the recommended daily dose of 9 vitamins or a placebo. Significant mood improvements were reported after 12 months, with males feeling more 'agreeable' and females experiencing better mental health, feeling more 'agreeable' and composed2. Interestingly, the blood levels of the vitamins plateaued after 3 months, but the mood improvements continued to develop over the year. This indicates that while biochemical changes may stabilize early, the psychological benefits of vitamin supplementation can take up to a year to fully manifest.
Conclusion
The time it takes for vitamins to take effect can vary based on the type of vitamin and the health outcome being measured. For periodontal health, vitamin D and calcium supplementation can show benefits within 6 months, with more significant improvements over a year. For mood enhancement, multivitamin supplementation may require up to a year to observe substantial benefits, despite blood levels stabilizing earlier. These findings highlight the importance of patience and consistency in vitamin supplementation to achieve desired health outcomes.
Sources and full results
Most relevant research papers on this topic
One-year effects of vitamin D and calcium supplementation on chronic periodontitis.
Vitamin D and calcium supplementation (1,000 IU/day) had a modest positive effect on periodontal health over a 1-year period, but consistent dental care improved clinical parameters regardless of supplementation.
Observational Study
Highly CitedVitamin supplementation for 1 year improves mood.
Vitamin supplementation for 1 year improves mood in both males and females, with riboflavin and pyridoxine status being key factors in mood improvements.
RCTHighly CitedStudy of the toxic effect and safety of vitamin E supplement in male albino rats after 30 days of repeated treatment
High doses of vitamin E supplementation for 30 days in male albino rats were not safe for the liver and kidney, but were safe for the testes, highlighting the need for caution when recommending it for therapeutic purposes.
RCT
Animal StudyAbsorption and retinol equivalence of β-carotene in humans is influenced by dietary vitamin A intake Published, JLR Papers in Press, June 1, 2003. DOI 10.1194/jlr.M300116-JLR200
Vitamin A supplementation increases absorption of -carotene, reducing urinary excretion and resulting in larger molar vitamin A values.
Effect of two different sublingual dosages of vitamin B12 on cobalamin nutritional status in vegans and vegetarians with a marginal deficiency: A randomized controlled trial.
Sublingual dosages of 350 g/week (350 g/day) of vitamin B12 are more effective than 2000 g/week (one large oral dose) in improving vitamin B12 nutritional status in vegans and vegetarians with a marginal deficiency.
RCT
Very Rigorous JournalThe impact of long-term vitamin supplementation on cognitive functioning
Long-term vitamin supplementation improves attention performance in females, suggesting females respond differently to dietary factors.
RCTPhotosynthesis of previtamin D3 in human skin and the physiologic consequences.
Photosynthesis of previtamin D3 in human skin occurs when exposed to solar ultraviolet radiation, and its slow, steady release into the circulation is a unique mechanism for vitamin D3 synthesis, storage, and release.
Highly CitedPeriodic administration of vitamin B2 and its effect on demand
Periodic administration of vitamin B2 reduces its effectiveness by four times compared to daily administration, making it recommended for systematic administration.
Non-RCTAnimal StudyVitamins, Are They Safe?
High-dose supplements of vitamins A, E, D, C, and folic acid may not always be effective for disease prevention and may even be harmful to the health.
Systematic Review