Stress and performance anxiety are common in sport. Here's what the evidence says about vitamin D and anxiety, signs of low vitamin D, and how much adults need.
🕒 6 min read
Stress and performance anxiety can affect athletes at any level. Training load, competition, injury, selection and the pressure to perform can all add to the everyday stresses of work, family and life.
Vitamin D is sometimes discussed alongside stress, anxiety and mood. Research has explored associations between vitamin D status and mental wellbeing, but vitamin D supplements should not be considered a treatment for stress or anxiety. Vitamin D does, however, have established roles in normal muscle function, the maintenance of normal bones and the normal function of the immune system.1
Can vitamin D help with stress and anxiety in sport?
Research into vitamin D and anxiety is still developing. Some studies have found associations between low vitamin D status and symptoms of anxiety or poorer mental wellbeing, but an association does not mean that low vitamin D directly causes anxiety.
A systematic review of randomised controlled trials found that evidence relating specifically to anxiety was limited and largely involved vitamin D being used alongside other treatments.2
For athletes, the practical priority is therefore to maintain an adequate vitamin D intake for its established roles in muscles, bones and immunity rather than taking vitamin D specifically to treat stress or performance anxiety.
Understanding performance anxiety
If you're involved in competitive sport, performance anxiety can occur before, during or after an event. You may worry about underperforming, losing your place in a team, meeting expectations or returning to competition following injury.
Some short-term stress can increase alertness and focus. However, when stress becomes excessive or persistent it may affect your enjoyment of sport, motivation and ability to concentrate.
Injury can create additional pressure. Worrying about recovery time, fitness, future competitions or team selection can all affect your mindset.
If anxiety is persistent, difficult to manage or affecting your everyday life, speak to your GP or another qualified healthcare professional. Nutrition can support general health, but it is not a substitute for appropriate mental health support.
Why is vitamin D important for athletes?
Vitamin D is a fat-soluble vitamin that contributes to several important functions relevant to active people. It contributes to:
- the maintenance of normal bones
- normal muscle function
- normal absorption and utilisation of calcium and phosphorus
- normal blood calcium levels
- the normal function of the immune system.
Research in athletes has also examined vitamin D supplementation in relation to strength, power, aerobic performance, inflammation and bone health. A 2024 systematic review of placebo-controlled trials in elite athletes found some potentially beneficial effects, but results varied between studies and outcomes.3
This means taking more vitamin D does not automatically lead to better sporting performance. Avoiding deficiency and maintaining adequate vitamin D status is the more appropriate goal.
How do you know if you're getting enough vitamin D?
Your body makes vitamin D when your skin is exposed to sunlight. Small amounts are also found in foods such as oily fish, egg yolks and fortified foods.
In the UK, most people can make the vitamin D they need from sunlight between late March or early April and the end of September. During autumn and winter, however, sunlight is not strong enough for most people to make sufficient vitamin D through their skin.4
Your sporting routine may also affect your exposure to sunlight. Athletes who train mainly indoors, exercise before sunrise or after sunset, or spend little time outside may receive less sunlight than they expect.
People with darker skin, those who cover most of their skin outdoors and people who spend very little time outside are also at greater risk of low vitamin D and are advised to consider supplementation throughout the year.4
Possible signs of significant vitamin D deficiency can include muscle weakness, bone discomfort or general aches, although symptoms can be vague and some people have no obvious symptoms.
Read our guide to vitamin D deficiency symptoms and how to get enough for more information.
How much vitamin D should athletes take?
There is no separate standard UK vitamin D recommendation simply because you are an athlete.
During autumn and winter, everyone should consider taking a daily supplement containing 10 micrograms (400 IU) of vitamin D. People at greater risk of vitamin D deficiency should consider taking this amount throughout the year.4
Some studies involving athletes use larger amounts of vitamin D, particularly when participants begin with low vitamin D status. These research doses should not be treated as general supplementation advice.
The NHS advises adults not to take more than 100 micrograms (4,000 IU) of vitamin D a day unless advised otherwise by a healthcare professional.4
If you're looking to supplement your intake, explore our range of vitamin D supplements.
What kind of vitamin D supplement should I take?
Vitamin D supplements are commonly available as vitamin D2 (ergocalciferol) or vitamin D3 (cholecalciferol). Vitamin D3 is also the form your skin naturally produces in response to sunlight.
If you follow a vegan diet, check the source of the vitamin D3, as some forms are derived from lanolin while vegan vitamin D3 is generally sourced from lichen.
Whichever format you choose, follow the directions on the product label and avoid combining several vitamin D-containing supplements without checking your total daily intake.
