Exercise: A Possibly Effective Way to Improve Vitamin D Nutritional Status

The effect of physical activity on vitamin D: A systematic review and meta-analysis of intervention studies in humans

Objectives

Cross-sectional studies demonstrate a positive association between higher physical activity and serum 25-hydroxyvitamin D (25(OH)D) concentration. However, whether this association is causal is unclear. We conducted a systematic review to identify intervention studies that examined the effect of physical activity on serum 25(OH)D concentration in humans.

Study design

Systematic review and meta-analysis.

Methods

We searched PubMed, Scopus and Web of Science to identify full-text peer-reviewed articles published in English from inception until January 2023. Eligible studies were randomised controlled trials or quasi-experimental studies. We used random effects meta-analysis to calculate the weighted mean difference (WMD) in the change in 25(OH)D concentration between physical activity and control groups. We used the revised Cochrane risk-of-bias tool for randomized trials (RoB 2) to assess the methodological quality of included studies.

Results

We included 32 articles in the systematic review and 24 in the meta-analysis. The intervention varied from resistance and weight-bearing exercises (n = 13) to aerobic exercises (n = 10), moderate and moderate-to-vigorous exercises (n = 5), aquatic exercise (n = 2), and multicomponent traditional exercises (n = 2) (Tai Chi and Yijinjing). The WMD in 25(OH)D in the physical activity and control groups was 9.51 and 4.87, respectively (between-group mean difference 4.64, p = 0.002). However, the difference was only evident in studies that implemented the intervention outdoors (n = 3; between-group mean difference 17.33, p < 0.0001); when the intervention was indoors there was no significant effect of physical activity on 25(OH)D (n = 16; between-group mean difference 1.80, p = 0.113).

Conclusions

This meta-analysis of physical activity interventions in humans showed that physical activity does not lead to increased 25(OH)D independently of time outdoors. However, most studies were under-powered, in many the exercise was low intensity, and vitamin D was not the primary outcome.

The effect of aquatic training and vitamin D3 supplementation on bone metabolism in postmenopausal obese women

Purpose

Despite prevalence of studies indicating the positive effect of land-based exercise on bone metabolism, there are limited findings regarding the effect of aquatic exercise. The present study aimed to evaluate the effects of aquatic training and vitamin D3 supplementation on femur bone mineral density (BMD), serum 25(OH)D, and parathyroid hormone (PTH) in postmenopausal obese women with vitamin D insufficiency.

Methods

40 postmenopausal obese women were randomly divided into four groups of aquatic training + vitamin D3 intake group; (ATD), aquatic training with placebo intake group (AT), vitamin D3 intake group (D), and control group with placebo intake (CON). AT groups performed aerobic aquatic exercises for 8 weeks. Vitamin D3 supplementation groups consumed oral dose of 4000 IU/d for 8 weeks.

Results

The femur BMD was significantly higher in the ATD than the AT and D and CON groups; in AT it was higher than the D and CON groups. Serum 25(OH)D level in the ATD was more than AT and CON, and in the D was more than the CON and AT. PTH in the ATD group was lower compared to AT, D, and CON groups. PTH was lower in the AT and D compared to the CON.

Conclusion

In postmenopausal obese women with vitamin D insufficiency or deficiency, combining vitamin D supplementation and aquatic training was the most effective method for improving bone metabolism; Vitamin D supplementation (alone) was not sufficient to affect some of bone metabolism indices; Aquatic training could not improve serum vitamin D. By priority, ATD, AT, and D indicated better bone related metabolism indices.

Joint association of sedentary behavior and vitamin D status with mortality among cancer survivors

BACKGROUND

Sedentary behavior and vitamin D deficiency are independent risk factors for mortality in cancer survivors, but their joint association with mortality has not been investigated.

METHODS

We analyzed data from 2914 cancer survivors who participated in the National Health and Nutrition Examination Survey (2007-2018) and followed up with them until December 31, 2019. Sedentary behavior was assessed by self-reported daily hours of sitting, and vitamin D status was measured by serum total 25-hydroxyvitamin D (25(OH)D) levels.

RESULTS

Among 2914 cancer survivors, vitamin D deficiency was more prevalent in those with prolonged daily sitting time. During up to 13.2 years (median, 5.6 years) of follow-up, there were 676 deaths (cancer, 226; cardiovascular disease, 142; other causes, 308). The prolonged sitting time was associated with a higher risk of all-cause and noncancer mortality, and vitamin D deficiency was associated with a higher risk of all-cause and cancer mortality. Furthermore, cancer survivors with both prolonged sitting time (≥ 6 h/day) and vitamin D deficiency had a significantly higher risk of all-cause (HR, 2.05; 95% CI: 1.54-2.72), cancer (HR, 2.33; 95% CI, 1.47-3.70), and noncancer mortality (HR, 1.91; 95% CI, 1.33-2.74) than those with neither risk factor after adjustment for potential confounders.

CONCLUSIONS

In a nationally representative sample of U.S. cancer survivors, the joint presence of sedentary behavior and vitamin D deficiency was significantly associated with an increased risk of all-cause and cancer-specific mortality.

Targeting neuroendocrine abnormalities in Parkinson's disease with exercise

Parkinson's Disease (PD) is a prevalent and complex age-related neurodegenerative condition for which there are no disease-modifying treatments currently available. The pathophysiological process underlying PD remains incompletely understood but increasing evidence points to multiple system dysfunction. Interestingly, the past decade has produced evidence that exercise not only reduces signs and symptoms of PD but is also potentially neuroprotective. Characterizing the mechanistic pathways that are triggered by exercise and lead to positive outcomes will improve understanding of how to counter disease progression and symptomatology. In this review, we highlight how exercise regulates the neuroendocrine system, whose primary role is to respond to stress, maintain homeostasis and improve resilience to aging. We focus on a group of hormones - cortisol, melatonin, insulin, klotho, and vitamin D - that have been shown to associate with various non-motor symptoms of PD, such as mood, cognition, and sleep/circadian rhythm disorder. These hormones may represent important biomarkers to track in clinical trials evaluating effects of exercise in PD with the aim of providing evidence that patients can exert some behavioral-induced control over their disease.

A Program of Life-Style Modification Improved the Body Weight and Micronutrient Status in Obese Patients after Bariatric Surgery

INTRODUCTION

Bariatric surgery is an efficient approach to rapidly reduce morbid obesity and associated comorbidities. However, approximately one-fourth of patients experience weight and comorbidity recurrence, and both obesity and bariatric surgery can lead to micronutrient deficiencies. Implementing a structured program of lifestyle modification (PLM) might enhance weight loss and improve micronutrient status.

METHODOLOGY

A total of 121 severely obese patients underwent Roux-en-Y gastric bypass (RYGB). Among them, 71 adhered to a PLM involving dietary changes (low- and very-low-calorie Mediterranean diets) and physical exercises (aerobic and resistance training) both before and after surgery, while 50 patients followed a conventional protocol. Anthropometric measurements and serological parameter quantifications were conducted throughout the procedures.

RESULTS

The obese study population, primarily female (76.9%), with an average age of 47.11 ± 9.68, and a body mass index (BMI) of 44.68 ± 5.08 kg/m2, underwent either RYGB with a PLM or a conventional procedure. Before surgery, the PLM group exhibited significant reductions in body weight (6.3%) and phosphoremia compared to the conventional protocol (0.78%). Post-RYGB, the PLM group demonstrated shortened in-hospital stays and further BMI reductions (-16.12 kg/m2) that persisted for up to 2 years. Furthermore, the PLM group experienced increased plasma vitamin D levels (14.79 ng/mL vs. 1.2 ng/mL) for up to 2 years, as well as elevated folic acid (1.52 vs. -0.29 ng/mL) and phosphorus (0.48 vs. 0.06 mg/dL) levels at 1 month and 1 year after intervention, respectively. Notably, these effects were independent of weight loss.

CONCLUSIONS

Initiating a structured PLM from the early stages of patients' preparation for RYGB could enhance and extend the benefits of weight loss and positively impact micronutrient (vitamin D, phosphorus, and folic acid) status in obese patients.

Prevalence, trend, and predictor analyses of vitamin D deficiency in the US population, 2001-2018

Background

The National Health and Nutrition Examination Surveys (NHANES) collect and release data to the public every 2 years. The latest NHANES study on the vitamin D status of Americans was based on data from 2001 to 2014, and the latest data (2015–2016 and 2017–2018) have not been studied yet. Thus, we extracted all the available data from NHANES (2001–2018), aiming to analyze the prevalence and trends of vitamin D deficiency (VDD) in the US population to bridge the research gap.

Methods

According to previous studies and nutritional guidelines for vitamin D, severe VDD was defined as serum 25(OH)D levels of <25 nmol/L, moderate deficiency as 25–50 nmol/L, insufficiency as 50–75 nmol/L, and sufficiency as >75 nmol/L. We comprehensively estimated the prevalence of serum 25(OH)D levels of <25, 25–50, 50–75, and >75 nmol/L in Americans and described trends in vitamin D status from 2001 to 2018. Weighted multivariate linear regression models were used to explore the predictors of VDD. All analyses and the data were adjusted for the complex sampling design of NHANES using Mobile Examination Center (MEC) weights.

Results

Based on the most recent data of 71,685 participants, our study showed that the weighted prevalence of severe and moderate VDD was 2.6% and 22.0%, and the prevalence of vitamin D insufficiency (VDI) and sufficiency was 40.9% and 34.5%. The prevalence of severe and moderate VDD was higher in women, non-Hispanic black Americans, people aged 20–29 years, and during the season of winter. From 2001 to 2018, we found a slight linear decrease in the prevalence of moderate VDD (coefficient = −0.847; P = 0.009) and VDI (coefficient = −0.810; P = 0.014). We also found a slight linear increase in vitamin D sufficient (coefficient = 1.693; P = 0.004). However, no trend change was observed in severe VDD (coefficient = −0.037; P = 0.698). Age, sex, ethnicity, season, sun-protective behaviors, lower BMI, lower socioeconomic status (SES), drinking, and lower milk consumption were predictors of severe VDD.

Conclusion

Vitamin D deficiency is still prevalent in the United States, especially in non-Hispanic black Americans, women, individuals aged 20–29, and during winter. Therefore, individuals, healthcare providers, and policymakers should take public health measures to develop and implement prevention strategies to deal with VDD.