The Effect of Abnormal Vitamin D Levels in Athletes

Association of Vitamin D Deficiency With Distal Biceps Injury: A Retrospective Analysis of 336,320 Patients

BACKGROUND

This study explores the association between vitamin D deficiency and distal biceps tendon injuries, illustrating that, although vitamin D deficiency is associated with prolonged hospital stays and various musculoskeletal problems, its connection to distal biceps tendon injuries is unknown.

HYPOTHESIS

Vitamin D deficiency is associated with an elevated risk of distal biceps injury but not with increased rates of subsequent surgery or revision surgery.

STUDY DESIGN

Case-control study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A 1:1 matched retrospective comparative study of 336,320 vitamin-D-deficient patients was performed using PearlDiver data (between January 1, 2011 and October 31, 2018). Cohorts, with a mean age of 55.7 ± 13.2 years, underwent multivariate logistic regression to calculate distal biceps tendon injury and surgical repair incidence according to age and sex, while controlling for demographics and comorbidities.

RESULTS

The 1-year incidence of distal biceps tendinopathy in vitamin-D-deficient patients was 118 per 100,000 person-years (95% CI) compared with 44.3 per 100,000 person-years in matched controls. Male patients with vitamin D deficiency were at a greater risk for distal biceps tendinopathy after 1 and 2 years (adjusted odds ratio [aOR] = 2.81, 2.08-3.83; aOR = 2.80, 2.21-3.56). Female patients were also at a greater risk after both years (aOR = 1.69, 1.27-2.27; aOR = 1.57, 1.26-1.96). Vitamin D deficiency was not associated with an elevated risk of surgical repair or revision surgery.

CONCLUSION

In a nationwide cohort, a diagnosis of vitamin D deficiency elevated the risk of distal biceps tendinopathy but did not raise the rate of surgical repair or revision. As a result, prevention strategies in the form of vitamin supplementation should be increased for athletes.Clinical Relevance: These findings emphasize the clinical relevance of monitoring vitamin D levels in patients at risk for musculoskeletal injuries, and providing adequate care to those involved in high-demand physical activities.Strength of Recommendation: B.

Prevalence of supplement usage and related attitudes and reasons among fitness athletes in the gyms of Kashan and its relationship with feeding behavior: a cross-sectional study

BACKGROUND

The overuse of supplements among athletes is a widespread issue affecting the health of both male and female athletes. However, research on supplements usage among female fitness athletes is limited, and there is little information on the feeding behavior of fitness athletes who use supplements. This study aimed to fill the gap in knowledge by examining the prevalence of supplement usage and its related attitudes and reasons among fitness athletes in the gyms of Kashan. It further aimed to investigate the correlation between supplements usage and the feeding behavior of fitness athletes.

METHODS

For these purposes, in this cross-sectional study, 433 fitness athletes (15‒46 years old) in 28 gyms in the city of Kashan were surveyed using a researcher-made questionnaire in 2023. Five experts confirmed the validity of the questionnaire. The present study considered the supplements based on the Australian Institute of Sport position statement. A Chi-square analysis was conducted to examine the relationship between the study variables and supplement usage.

RESULTS

Overall, 272 male and 161 female fitness athletes participated in this study. The results revealed that 57.9% of participants used supplements, most commonly vitamin C, vitamin D, omega-3 fatty acids, and whey protein. The main reason for using supplements was to speed up body repair after exercise (69.5%). Additionally, 41.8% of these athletes believed that using supplements improves their overall performance, and 21.9% thought that supplements do not harm the body. Moreover, a correlation was observed between feeding behavior and the consumption of supplements. It was found that athletes who use supplements tend to eat more white meat, seeds, and nuts and fewer high-fat dairy products than those who do not consume them.

CONCLUSION

Using supplements among fitness athletes in the gyms of Kashan is common. The main reason for using these substances was to speed up body repair after exercise, and nearly half of the athletes believed that supplements improved their performance. In addition, it was revealed that athletes who take supplements have healthier feeding behaviors than those who do not. Thus, these findings confirm the necessity of informing fitness athletes about using supplements.

Vitamin D Deficiency in Professional Football Players during Competitive Season of Italian First Division (Serie A)

BACKGROUND

Data in the literature have demonstrated the crucial role that vitamin D plays in the human organism, and recent studies also emphasize this essential role of vitamin D in athletes. Indeed, vitamin D acts on the skeletal muscles and plays a fundamental role in numerous physiological processes involved in immune function. Many factors such as sun exposure, skin tone, body mass index and chronic illness affect vitamin D levels. The aim of the study is to evaluate vitamin D levels in professional football players in Italy and investigate the variations in vitamin D values in footballers who train at different latitudes.

METHODS

The study performed is a retrospective observational study analyzing 25-OH vitamin D values in professional football players of the Italian First Division (Serie A). Two teams during the competitive season were selected: team A (latitude of 41° N in southern Italy) and team B (latitude of 45° N in northern Italy). Three time periods were identified and were classified as follows: the first quarter (May, June, July, and August), the second quarter (September, October, November, and December) and the third quarter (January, February, March, and April). The purpose of this was to study the average values of vitamin D during the year corresponding to different levels of sunlight exposure. Each athlete was subjected to at least one sampling during the three quarters of the competitive season.

RESULTS

Both vitamin D insufficiency (10.1%) and overt deficiency (1.93%) were found in Italian Serie A players. Insufficient vitamin D values are between 20 ng/mL and 29 ng/mL and overt deficiency values <20 ng/mL. At the same time, the data demonstrated a significant variation in vitamin D values depending on the period of the competitive season and the latitude of the cities of the two teams. In detail, there was no significant difference in the first quarter, while there was a significant increase in vitamin D values in team B in the second and third quarter, at p < 0.01 and p < 0.05, respectively.

CONCLUSIONS

Latitude and seasons have a significant impact on vitamin D levels. Therefore, it is essential to measure vitamin D in professional football players, especially during the spring and winter months, so as to monitor changes in levels in relation to the season and latitude and evaluate any supplements. Further studies should be performed to evaluate the relationship between vitamin D deficiency and football players' athletic performance.

A FOUR-YEAR CYCLE COMPARISON OF THE NUTRITIONAL AND CARDIOVASCULAR HEALTH STATUS OF AN ELITE-LEVEL FEMALE ARTISTIC GYMNAST: CASE STUDY REPORT FROM SLOVENIA

Regular monitoring of body composition, nutrition, health, and motor skills are crucial for further training process planning and performance progress. With the same protocol and methods, we evaluated a four-year change (2018 vs. 2022) in the nutritional and cardiovascular health status of the currently most successful elite-level adult female artistic gymnast in Slovenia. Detailed body composition and dietary intake were assessed using dual-energy X-ray absorptiometry and a standardized food questionnaire FFQ. The blood lipids and safety factors, blood pressure, and serum micronutrients (e.g., B12, 25-hydroxyvitamin D (25(OH)D), potassium, calcium, phosphorus, magnesium, and iron) status were measured. The four-year comparison showed an improved body composition status: decreased body fat mass/percentage, android fat percentage, and android/gynoid ratio, while other anthropometrical and body composition parameters remained essentially unchanged. We also measured an improvement of some and worsening of other cardiovascular health serum variables (i.e., decreased total cholesterol but increased low-density lipoprotein cholesterol and S-glucose), most likely due to the differences in assessed dietary intake (i.e., lower total fat, mono- and polyunsaturated fatty acid intake but higher cholesterol intake and still high free sugar and saturated fat intake, despite higher fiber). Notably, nutrient intakes that are generally of concern (fiber (borderline low intake), eicosapentaenoic omega-3 fatty acids and docosahexaenoic omega-3 fatty acids, vitamin B12 and D, calcium (borderline low intake), iron, and zinc) were within recommended ranges. However, the athlete’s vitamin E and potassium intakes were not adequate. Furthermore, in 2018, the athlete did not consume dietary supplements, while she now regularly uses several dietary supplements, including enriched plant-based protein powder, isolated vitamin B12, C, D, and iron. Moreover, the athlete had significantly lower than recommended serum levels of 25(OH)D, probably due to insufficient regular intake of vitamin D in the form of a dietary supplement (1000 IU/d). Moreover, from the micronutrient serum, phosphorus, and iron levels that deviated from the reference values in the 2018 study, in the current study, they were found to be within referenced ranges (i.e., iron status was markedly improved). This kind of screening toolbox, using valid, sensitive, and affordable methods and with rapid organizational implementation, may be a viable format for regular monitoring.

Biocompatible Nanoparticle Heteroaggregates as Stabilizers of Pickering Emulsions for Vitamin D3 Efficient Delivery

Vitamin D3 deficiency is a major public health problem worldwide, and standard cholecalciferol formulations provide poor absorbability of the vitamin. Several biphasic formulas have been proposed to overcome the disadvantages in which Pickering emulsions stand out in particular. This paper describes olive oil-in-water Pickering emulsions stabilized by pseudoboehmite (AlOOH), cellulose nanocrystals (CNC), and their heterocoagulates. Colloidal properties were assessed by laser Doppler microelectrophoresis, potentiometric titration, and rheology. It was shown that the heterocoagulation of CNC and AlOOH led to a drastic change in surface properties (ζ-potential, pKa, and number of active centers), which promoted the formation of more stable emulsions with the smallest size of droplets and the highest viscosity among the studied samples. Simulated digestion studies showed the targeted release in the small intestine medium where cholecalciferol should be delivered. High-performance liquid chromatography showed the efficient encapsulation of cholecalciferol in emulsions (86% of initial concentration). Oral administration to laboratory mice of initial nanoparticles and emulsions stabilized by them showed nontoxicity for all of the components, and they were estimated to be class V materials. The proposed emulsions have great potential as targeted delivery systems of lipophilic drugs.

Challenges Ahead for a Rational Analysis of Vitamin D in Athletes

Vitamin D is an essential vitamin for the normal formation of bones and calcium absorption. It is synthesized into our body through sunlight exposure and obtained by consuming foods rich in vitamin D (e.g., fatty fish, eggs yolk, dairy products). Its benefits on the health and performance of athletes are well documented. This article outlines some analytical challenges concerning the analytical quantification of vitamin D for its optimal intake, namely, a comprehensive study of the variability of the assay before categorizing any method as the golden standard, assurance of sample comparability to draw meaningful correlations, revision of the intake guidance based on appropriate statistical power analysis, and the implementation of rational strategies for preventing the underlying mechanism of preanalytical factors. Addressing these challenges will enable the effective management of vitamin D in the sports sector.

Vitamin D in athletes: focus on physical performance and musculoskeletal injuries

PURPOSE

The aim of this review was to discuss the effects of vitamin D on physical performance and musculoskeletal injuries in athletes and provide information on the field applications of vitamin D.

METHODS

A systematic review was conducted to identify studies on vitamin D in athletes that assessed serum vitamin D levels, vitamin D and physical performance, vitamin D and musculoskeletal injuries, and practical guidelines for supplementation of vitamin D.

RESULTS

Several studies reported that a high proportion of athletes had vitamin D insufficiency or deficiency. Low serum levels of vitamin D in athletes were more pronounced in winter than in other seasons, and indoor athletes had lower serum vitamin D levels than outdoor athletes. Low vitamin D levels have been demonstrated to have negative effects on muscle strength, power, and endurance; increase stress fractures and other musculoskeletal injuries; and affect acute muscle injuries and inflammation following high-intensity exercises. Therefore, periodic assessment and monitoring of vitamin D levels are necessary in athletes; the recommended serum level of 25(OH)D is &gt; 32 ng/mL and the preferred level is &gt; 40 ng/mL (-1). In those with low levels of vitamin D, exposure to sunlight and an improved diet or supplements may be helpful. Particularly, 2000-6000 IU of supplemental vitamin D3 can be consumed daily.

CONCLUSION

Vitamin D is a potential nutritional factor that can significantly affect physical performance and musculoskeletal injuries in athletes. The importance and role of vitamin D in athletes should be emphasized, and the current levels of vitamin D should be assessed. Therefore, it is essential to periodically evaluate and monitor serum vitamin D levels in athletes.

Vitamin D and Stress Fractures in Sport: Preventive and Therapeutic Measures-A Narrative Review

There are numerous risk factors for stress fractures that have been identified in literature. Among different risk factors, a prolonged lack of vitamin D (25(OH)D) can lead to stress fractures in athletes since 25(OH)D insufficiency is associated with an increased incidence of a fracture. A 25(OH)D value of <75.8 nmol/L is a risk factor for a stress fracture. 25(OH)D deficiency is, however, only one of several potential risk factors. Well-documented risk factors for a stress fracture include female sex, white ethnicity, older age, taller stature, lower aerobic fitness, prior physical inactivity, greater amounts of current physical training, thinner bones, 25(OH)D deficiency, iron deficiency, menstrual disturbances, and inadequate intake of 25(OH)D and/or calcium. Stress fractures are not uncommon in athletes and affect around 20% of all competitors. Most athletes with a stress fracture are under 25 years of age. Stress fractures can affect every sporty person, from weekend athletes to top athletes. Stress fractures are common in certain sports disciplines such as basketball, baseball, athletics, rowing, soccer, aerobics, and classical ballet. The lower extremity is increasingly affected for stress fractures with the locations of the tibia, metatarsalia and pelvis. Regarding prevention and therapy, 25(OH)D seems to play an important role. Athletes should have an evaluation of 25(OH)D -dependent calcium homeostasis based on laboratory tests of 25-OH-D3, calcium, creatinine, and parathyroid hormone. In case of a deficiency of 25(OH)D, normal blood levels of ≥30 ng/mL may be restored by optimizing the athlete's lifestyle and, if appropriate, an oral substitution of 25(OH)D. Very recent studies suggested that the prevalence of stress fractures decreased when athletes are supplemented daily with 800 IU 25(OH)D and 2000 mg calcium. Recommendations of daily 25(OH)D intake may go up to 2000 IU of 25(OH)D per day.

Vitamin D Deficiency is Associated with Handgrip Strength, Nutritional Status and T2DM in Community-Dwelling Older Mexican Women: A Cross-Sectional Study

The aim of this study was to evaluate the association between handgrip strength, nutritional status and vitamin D deficiency in Mexican community-dwelling older women. A cross sectional study in women ≥ 60 years-old was performed. Plasma 25-hydroxyvitamin D (25(OH)D) concentrations were measured by a quantitative immunoassay technique. Handgrip strength was assessed using a dynamometer, while nutritional status was assessed through the Full Mini Nutritional Assessment (Full-MNA). A total of 116 women participated in the study, their mean age was 70.3 ± 5.8 years; 49.1% of the study group had plasma 25(OH)D levels lower than 40 nmol/L [16 ng/mL]. Meanwhile, 28.45% of participants had low handgrip strength (<16 kg), and 23.1% were identified at risk of malnutrition/malnourished according with Full-MNA score. Women with 25(OH)D deficiency (<40 nmol/L [16 ng/mL]) were more likely to have low handgrip strength (OR = 2.64, p = 0.025) compared with those with higher 25(OH)D values. Additionally, being malnourished or at risk of malnutrition (OR = 2.53, p = 0.045) or having type 2 diabetes mellitus (T2DM) (OR = 2.92, p = 0.044) was also associated with low 25(OH)D. The prevalence of low plasma 25(OH)D concentrations was high among Mexican active older women. Low handgrip strength, being at risk of malnutrition/malnourished, or diagnosed with T2DM was also associated with Vitamin D deficiency.

Adolescent Athlete Stress Fractures Associated with Vitamin D Insufficiency: Three Cases with Review of the Literature

CASE

The authors present 3 adolescent athletes who presented with stress fractures in their lower extremities, initially diagnosed as tumors. All 3 patients received an inconclusive magnetic resonance imaging before referral; fractures were confirmed on radiographs and computed tomography. All were found to have vitamin D insufficiency.

CONCLUSIONS

Vitamin D insufficiency is a global epidemic mainly focused on adults and young-adult athletes. These case reports raise concerns about a growing prevalence of vitamin D insufficiency in adolescents, the potential risk of stress fracture, and the need for screening and possible supplementation in adolescent athletes to improve their bone health.

Five-Year Surveillance of Vitamin D Levels in NCAA Division I Football Players: Risk Factors for Failed Supplementation

Background

Monitoring vitamin D levels in athletes and determining their response to supplementation in cases of deficiency is thought to be necessary to modulate the risks associated with vitamin D deficiency.

Hypothesis/Purpose

To report the results of a 5-year-long surveillance program of vitamin D in the serum of football players on a National Collegiate Athletic Association (NCAA) Division I team and to examine whether factors including age, body mass index (BMI), race, position played, and supplement type would affect the response to 12-month oral vitamin D replacement therapy in athletes with deficiency. We hypothesized that yearly measurements would decrease the proportion of athletes with vitamin D insufficiency over the years and that the aforementioned factors would affect the response to the supplementation therapy.

Study Design

Cohort study; Level of evidence, 3.

Methods

We measured serum 25(OH)D levels (25-hydroxyvitamin D) in 272 NCAA Division I football players from our institution annually between 2012 and 2017. Athletes with insufficient vitamin D levels (<32 ng/mL) received supplementation with vitamin D3 alone or combined vitamin D3/D2. The percentage of insufficient cases between the first 2 years and last 2 years of the program was compared, and yearly team averages of vitamin D levels were calculated. Associations between player parameters (age, BMI, race, team position, supplement type) and failed supplementation were evaluated.

Results

The prevalence of vitamin D insufficiency decreased significantly during the study period, from 55.5% in 2012-2013 to 30.7% in 2016-2017 (P = .033). The mean 25(OH)D level in 2012 was 36.3 ng/mL, and this increased to 40.5 ng/mL in 2017 (P < .001); however, this increase was not steady over the study period. Non-Hispanic athletes and quarterbacks had the highest average 25(OH)D levels, and Black players and running backs had the lowest overall levels. There were no significant differences in age, BMI, race, or playing position between athletes with and without failed vitamin D supplementation. Athletes receiving vitamin D3 alone had a more successful rate of conversion (48.15%) than those receiving combined vitamin D3/D2 (22.22%; P = .034).

Conclusion

To decrease the prevalence of vitamin D deficiency in football players, serum vitamin D measurements should be performed at least once a year, and oral supplementation therapy should be provided in cases of deficiency. Black players might be at increased risk of vitamin D insufficiency. Oral vitamin D3 may be more effective in restoring vitamin D levels than combined vitamin D3/D2 therapy.

Nutritional Status and Cardiovascular Health in Female Adolescent Elite-Level Artistic Gymnasts and Swimmers: A Cross-Sectional Study of 31 Athletes

OBJECTIVE

Nutritional status is important for health and competitive achievement. This area remains understudied among elite-level female athletes and is appropriate for research. We examined nutritional status and cardiovascular health markers of two groups of female athletes of the same age and competition period, involved in weight-bearing and a non-weight-bearing sport: gymnasts (n = 17) and swimmers (n = 14); mean age 17.4 and 16.6 years.

METHODS

Body composition and dietary intake were assessed by bioelectrical impedance and Food Frequency Questionnaire. The concentrations of serum micronutrients (B12, 25-hydroxyvitamin D (25 (OH) D), calcium, magnesium, phosphorus, potassium, and iron), blood lipids, and blood pressure (BP) were measured. Setting and Participants. A cross-sectional study of 31 athletes from Slovenia.

RESULTS

Gymnasts had higher body mass index (21.5 vs. 20.1 kg/m2, p=0.043) and lower fat free mass (42.4 vs. 46.6 kg, p=0.024) than swimmers and comparable body fat percentage (22.5 vs. 22.8%). Both groups had low intake of carbohydrates, fibre, polyunsaturated fats, protein (only gymnasts), and micronutrients (11/13 micronutrients gymnasts and 4/13 swimmers) and high intake of free sugars and saturated fats. Both groups also had significantly lower-than-recommended serum levels of 25 (OH) D. All cardiovascular risk factors were within recommended ranges. Gymnasts had higher LDL cholesterol (2.7 vs. 2.2 mmol/L, p < 0.011), and swimmers had higher systolic BP (126 vs. 107 mmHg, p < 0.001).

CONCLUSIONS

Dietary intake especially in gymnasts was suboptimal, which may reflect in anthropometric and cardiovascular marker differences between gymnasts and swimmers.

Vitamin D, sport and health: a still unresolved clinical issue

Vitamin D metabolites have a pleiotropic role in human physiology, both in static and dynamic conditions, and a lot of vitamin D-related biological effects could influence physical and sport performances in athletes. Probably due to different factors (e.g., drugs, doping, nutrition, ultraviolet B radiation exposure), in athletes a very high prevalence of vitamin D inadequacy (i.e., deficiency or insufficiency) has been observed. Vitamin D inadequacy in athletes could be associated with specific health risks and to alterations of functional capacities, potentially influencing the fine adjustment of physical performances during training and sport competitions. When risk factors for vitamin D inadequacy exist, a preventive vitamin D supplementation is indicated, and if a vitamin D inadequacy is diagnosed, its supplementation is recommended. Unfortunately, on these issues many concerns remain unresolved. Indeed, it is not clear if athletes should be classified as a special population at increased risk for vitamin D inadequacy; moreover, in comparison to the non-athletic population, it is still not clear if athletes should have different reference ranges and different optimal target levels for serum vitamin D, if they have additional health risks, and if they need different type of supplementations (doses) for prevention and/or replacement therapy. Moreover, in athletes also the abuse of vitamin D supplements for ergogenic purposes raise different ethical and safety concerns. In this review, the main physio-pathological, functional and clinical issues that relate vitamin D to the world of athletes are described.

Comparison of Energy and Nutrient Intake vs. Estimated Needs in Warfighters: an Update

Active members of the military must perform optimally under conditions of thermal stress and/or energy deficiency. Military dietary reference intakes (MDRIs) provide guidelines for energy and nutrient intakes but is based studies largely conducted in Army. Needs may vary by service branch and/or position. New protein recommendations have emerged, which are not reflected in MDRIs. PURPOSE OF REVIEW: Compare reported dietary intake in active duty members to MDRIs and 2016 American College of Sports Medicine (ACSM) sports nutrition guidelines. RECENT FINDINGS: Active duty members are not meeting their energy and carbohydrate needs with low-to-adequate protein intake and adequate-to-high fat intake. Other nutrients of concern are vitamin D, calcium, iron, B-vitamins, and fiber. Thermal stress increases energy needs and suppresses appetite and thus increase risk for energy and nutrition deficiencies. Energy and nutrients needs can vary by branch of armed service, job responsibility, and external stressors.

Treating Vitamin D Deficiency and Insufficiency in Chronic Neck and Back Pain and Muscle Spasm: A Case Series

INTRODUCTION

The association between vitamin D deficiency or insufficiency and pain in the musculoskeletal system, especially in the neck and/or back regions, and/or muscle spasm is not well studied. The results of the limited studies have been mixed.

CASE PRESENTATION

The goal of this report is to examine the association between vitamin D deficiency and insufficiency and chronic neck and back pain and muscle spasm and the role of correction of vitamin D deficiency and insufficiency in the treatment of chronic pain and muscle spasm, especially in the neck and back regions. This case series reviewed medical records to identify patients with chronic pain (lasting from 6 months to 1 year) in the neck and back regions that improved significantly through the correction of the vitamin D deficiency or insufficiency. Patients were referred to the spine clinic of a tertiary hospital in a major metropolitan area in the Northwest by their primary care physicians after physical therapy and after first-tier pain medications, including nonsteroidal anti-inflammatory drugs, had failed. Some of the patients had epidural steroid injections without significant relief. The blood vitamin D level was tested at the clinical laboratory, and patients were given 50,000 IU of oral vitamin D once a week for 12 weeks. The main outcome measures were patient self-reported visual analog scale score and degree of muscle spasm. The 4 patients included in this series all had more than 70% improvement in their symptoms after taking 50,000 IU of vitamin D once a week for 12 weeks.

DISCUSSION

Vitamin D deficiency and insufficiency can cause or worsen neck and back pain and muscle spasm. The correction of vitamin D deficiency and insufficiency plays an important role in the treatment of chronic neck and back pain and muscle spasm among patients having concurrent vitamin D deficiency and insufficiency because it can be prevented and treated easily.Given the high health care expenditure on the treatment of chronic neck and back pain, prompt and accurate diagnosis and treatment of vitamin D deficiency and insufficiency not only increase the quality of care but also reduce the cost.