Vitamin D in spring: why it matters for wellbeing, immunity and skin
At the beginning of spring, vitamin D levels are often at their lowest point of the year - particularly in the UK.
After months of weaker winter sunlight, the body’s vitamin D stores can become depleted. Even when the days begin to lengthen in March and April, it can take time for levels to recover again. That seasonal dip matters, because vitamin D supports far more than bone health alone. It plays an important role in immune function, muscle health and broader wellbeing too.
For anyone following a plant-based or vegan diet, vitamin D can need a little more attention. Unlike some other nutrients, there are relatively few natural vegan food sources, which means spring is a useful moment to check in and think about how you’re supporting your levels.
Why are vitamin D levels often lowest in early spring?
Vitamin D is made when the skin is exposed to UVB sunlight. In the UK, the NHS advises that from about late March or early April to the end of September, most people should be able to make the vitamin D they need from sunlight on the skin. But between October and early March, sunlight is not strong enough for the body to make enough vitamin D.
That means winter becomes a kind of depletion period. We spend less time outdoors, skin is more covered, and the body gradually uses stored vitamin D. By the time early spring arrives, levels can still be lagging behind, even though brighter days are beginning to return.
Why is vitamin D so important?
Vitamin D is often thought of only in relation to bones, but its role is wider than that.
It helps the body absorb calcium and phosphorus, which are essential for maintaining strong bones and teeth. Without enough vitamin D, bone health can be affected over time. In severe deficiency, this can contribute to conditions such as rickets in children and osteomalacia in adults.
Vitamin D also supports normal muscle function and is involved in immune regulation. Research continues into its wider role in the body, including inflammation and cell growth, heart health, diabetes, and autoimmune diseases, though not all connections are proven yet.
Some people with low vitamin D levels also notice symptoms such as tiredness, general aches and pains, or low mood - although these symptoms can have many possible causes, so it is always worth speaking to a GP if something feels persistently off.
What about vitamin D and the skin?
Vitamin D has an interesting relationship with skin health.
The skin is involved in producing vitamin D in response to sunlight, but vitamin D is also active within the skin itself. It's involved in processes linked to skin barrier function, immune signalling and normal skin cell turnover. This is one reason it continues to attract interest in dermatology research.
Low vitamin D status has been associated in research with certain inflammatory skin conditions, including eczema and psoriasis, and may play a role in skin barrier health. But it's important not to oversimplify this - dry, dull or reactive skin is rarely caused by one factor alone, and vitamin D is not a quick fix for every skin concern.
A better way to think about it is that vitamin D is one part of the wider picture that supports healthy skin, alongside a balanced diet, barrier-supportive skincare, sleep, stress management and appropriate sun protection.
Vitamin D and vegan diets
Vitamin D can be particularly important to consider on a vegan diet, simply because food sources are more limited.
Useful vegan sources include:
- UV-exposed mushrooms
- Fortified plant milks
- Fortified breakfast cereals
- Fortified spreads
Even with these foods, it can still be difficult to get enough vitamin D from diet alone. That is why guidance commonly recommends a daily supplement during the autumn and winter months, and year-round for some people who are at higher risk of deficiency. For vegans, vitamin D2 and lichen-derived vitamin D3 are good options to look for.
10 simple ways to support your vitamin D through spring and summer
1. Make the most of regular daylight
As the season changes, consistent exposure to natural daylight becomes more useful again. A short walk outdoors most days can help support vitamin D production, especially from late March or early April onwards in the UK.
2. Aim for brief, sensible sun exposure
You don't need hours in the sun (and we wouldn't recommend it!). Small amounts of everyday exposure can be enough for many people, especially those with lighter skin. The goal is not tanning or burning - just regular, moderate daylight exposure.
3. Remember that skin tone matters
People with darker skin may need longer sun exposure to maintain optimal vitamin D levels, because higher melanin reduces vitamin D production from sunlight.
4. Don’t rely on food alone
Vitamin D is found naturally in only a small number of foods, and vegan sources are narrower still. Fortified foods can help, but they are not always enough by themselves.
5. Prioritise fortified vegan staples
Check labels on plant milks, cereals and spreads. Small choices made consistently can make a real difference over time.
6. Include UV-exposed mushrooms
They are one of the most useful plant-based food sources of vitamin D and an easy addition to salads, grain bowls, soups and simple spring cooking.
7. Consider whether a supplement still makes sense
The NHS advises that adults and children over 1 year need 10 micrograms of vitamin D a day, and that everyone should consider taking a daily supplement during autumn and winter. Some people at higher risk of deficiency are advised to supplement throughout the year.
8. Use sunscreen smartly
Use sunscreen after your short “vitamin D window” This protects against skin damage while still allowing some vitamin D production.
9. Think about your lifestyle
If you spend most of the day indoors, cover most of your skin outside, or avoid sunlight altogether, your vitamin D levels may need extra support.
10. Get checked if you’re concerned
If you are dealing with ongoing fatigue, aches, low mood, or think you may be at risk of deficiency, a GP can advise whether a blood test is appropriate. Vitamin D is important, but more is not always better - so it is best not to guess with high-dose supplements.
A seasonal reminder
Spring is often when we start thinking about renewal - lighter routines, more time outdoors, and a sense of energy returning again. It is also a good time to remember that vitamin D levels may still be recovering from winter.
For those following a vegan lifestyle especially, a little more awareness can go a long way. Sensible sunlight, fortified foods, and the right supplement where needed can all help support healthier levels as the season shifts.
And while vitamin D is only one part of the picture, it is one of those quiet foundations that can influence how we feel - from resilience and energy to the way our skin functions day to day.