Vitamin D levels in elite Spanish team players over a season
What it found
In 95 elite male players at Football Club Barcelona, average vitamin D was above the optimal level, but about a quarter fell below it at some point, with the lowest levels in spring.
Outdoor training plus supplements was linked to the highest levels.
What they found
Studies in people
Average vitamin D level
The average vitamin D level across all players for the whole year was 91.9 nmol/L. About 25% of players were below the optimal level of 75 nmol/L, but none were below 50 nmol/L.
Seasonal changes
Vitamin D was highest in autumn and lowest in spring. The highest rate of insufficiency was in spring at 40%, followed by winter at 35% and autumn at 10%.
Outdoor versus indoor training
Players who trained outdoors had higher average vitamin D (99.5 nmol/L) than those who trained indoors. Basketball players, who trained indoors, had the lowest levels.
Supplement use
About 42% of players took vitamin D supplements from October to June. Supplemented players had higher average vitamin D (94.7 nmol/L) than non-supplemented players, and the difference was significant for football players.
Outdoor training plus supplements
Players who trained outdoors and took supplements had the highest vitamin D levels (105 nmol/L) compared with those training indoors with or without supplements (84.6 nmol/L).
Skin color
Caucasian players had significantly higher vitamin D levels than Black players. Only four dark-skinned players were studied, so the authors say more research is needed.
What the authors conclude
“Spanish team players show a risk of hypovitaminosis D.”
Also in their conclusions
- They say Spanish team players show a risk of low vitamin D, with season, skin color, outdoor training and supplementation being the most important factors.
- They recommend routine screening of vitamin D status, especially in winter, to keep levels at or above 75 nmol/L and preferably at or above 100 nmol/L in autumn.
- They advise regular safe sun exposure with outdoor training and/or dietary supplements, especially for basketball or handball players.
How it was done
Low vitamin D is common, but there was little information on elite team players, especially first division players. The authors wanted to see how training environment, skin color, sport, season and supplements affect vitamin D over a season.
They measured blood vitamin D in 95 male elite players from six sports at Football Club Barcelona, three times during the 2011-2012 season. They also recorded whether players trained indoors or outdoors and whether they took vitamin D supplements.
What it can’t tell you
- This study followed players over one season and cannot prove that training outdoors or taking supplements directly caused the differences in vitamin D levels.
- The results are from 95 male elite players at one club, so they may not apply to other people or other teams.
- The authors did not use the gold standard lab method for vitamin D and could not measure other related factors like parathyroid hormone or calcium.
Who paid
- Funding
- Funded by Instituto de Salud Carlos III (from the PubMed record).
- Conflicts
- The authors declare no conflict of interest.
- Authors work at
- Instituto de Salud Carlos III (ISCIII), Spain; GIRSANE-CAR (Centre d'Alt Rendiment Sant Cugat del Vallès), Spain
The paper
- Title
- Vitamin D Status in Spanish Elite Team Sport Players
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Valtueña J, Aparicio-Ugarriza R, Medina D, et al (2021). Vitamin D Status in Spanish Elite Team Sport Players. Nutrients. doi:10.3390/nu13041311Free full textPubMed 33921150DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error