An analysis of the landmark VITAL trial has rekindled the debate over the benefits, or lack thereof, seen in vitamin D supplementation, and the determinants of whether patients benefit are: body mass index (BMI).
Results from analyzes stratifying patients according to baseline BMI suggest that among patients in the Vitamin D and Omega-3 Trial (VITAL), blunted responses were observed in overweight or obese patients .
“This study reveals why vitamin D supplementation reduces cancer deaths, autoimmune diseases, and other outcomes by 30-40% in people with low BMI, but has little effect in people with high BMI. said Joanne E. Manson, M.D., DrPH, Senior Investigator, Director of Preventive Medicine at Brigham and Women’s Hospital and Principal Investigator at VITAL. Statement from Brigham and Women’s Hospital“These nuances reveal that there is more to the vitamin D story.”
When it comes to overall health effects, few items have received as much public attention or as intensive research as vitamin D, with the exception of coffee and caffeine. , the VITAL trial was born to provide clearer answers to questions about vitamin D supplementation. Designed specifically to evaluate the effects of daily high-dose vitamin D on cancer and cardiovascular disease prevention, this study randomized his 25,871 adults who were followed for an average of 5.3 years. has registered.
The results of the trial showed that daily vitamin D supplementation failed to significantly reduce the risk of cancer, cardiovascular disease, or stroke in the study cohort. However, researchers observed statistical correlations between BMI and cancer incidence, cancer mortality, and autoimmune disease incidence. The current study was designed as a post hoc analysis of the VITAL trial to test the researchers’ hypothesis that obesity alters vitamin D metabolism and response to supplementation. Restricting the analysis to patients with baseline vitamin D analysis, the researchers identified a cohort of her 16,155 patients to include in the analysis.
The study cohort had a mean age of 67.7 (SD, 7.0) years, was 50.7% female, and 76.9% non-Hispanic white. Of note, of her 16,155 patients included in the researchers’ analysis, 2,742 of them had follow-up blood samples taken two years later. Researchers found that those who were baseline overweight or overweight (40.5%) or obese (27.0%) were generally younger, more likely to self-report black race or ethnicity, and had higher annual household income. low and pointed out that the level of education achieved was lower than theirs. Normal weight opponent.
Prior to randomization, serum total 25-OHD levels progressively decreased with increasing BMI category. The adjusted mean for each BMI category is highlighted below (P. <.001 linear trend).
- Underweight: 32.3 (SE, 0.7) ng/mL
- Normal body weight: 32.3 (SE, 0.1) ng/mL
- Overweight: 30.5 (SE, 0.1) ng/mL
- Obesity class I: 29.0 (SE, 0.2) ng/mL
- Obesity Class II: 28.0 (SE, 0.2) ng/mL
Further analysis showed that baseline levels of 25-OHD3, FVD, BioD, VDBP, albumin, and calcium levels were lower in higher BMI categories.In contrast, PTH levels appeared to increase with increasing BMI category (all P. <.001 linear trend).
Randomization to daily vitamin D supplementation was associated with increased 25-OHD, 25-OHD3, FVD, and BioD levels compared to placebo over 2 years after evaluating the effect of randomization. However, the researchers noted that the increases were significantly higher in the higher BMI categories. Furthermore, no substantial changes in VDBP, albumin, PTH, or calcium levels were observed as a result of vitamin D supplementation.
“Analysis of the original VITAL data found that vitamin D supplementation had a positive effect on some health outcomes, but only among those with a BMI less than 25.” preventive medicine. “There seems to be something else going on with vitamin D metabolism when you gain weight, and this study may help explain the diminished results of supplementation in people with high BMI.”
This studyAssociation between body weight and response to vitamin D supplementation and metabolismwas published in JAMA network opened.