Why Half of UK Adults Are Missing Out on the Sunshine Vitamin This Winter

Published by The Online GP | 5 minute read

As we navigate another British winter, there's something happening inside your body that you can't see or feel—yet it affects everything from your bones to your mood. We're talking about vitamin D deficiency, and if you're reading this in the UK, there's a 50% chance your levels are lower than optimal right now.

The Hidden Epidemic in Plain Sight

Recent data from February 2025 shows that 50% of UK adults have lower than optimal vitamin D levels. Think about that for a moment—half of us are walking around with insufficient amounts of a vitamin that's crucial for our health.

The situation is even more concerning for certain groups. If you're of Asian heritage living in the UK, the statistics are particularly sobering: 57 per cent of Asians were severely deficient in vitamin D (levels below 25 nmol/L) in winter/spring. For Black Africans, it's 38.5%, and even among white Europeans, nearly one in five show deficiency during winter months.

Why the UK Has a Unique Problem

Living between the 50th and 60th parallels north, the UK faces a peculiar challenge. From October through March, the sun simply isn't strong enough to trigger vitamin D production in our skin, no matter how long we spend outdoors. In the autumn and winter months in the UK (October to early March), there is no sunlight of appropriate wavelength for synthesis of vitamin D.

Even our famous British stoicism can't overcome basic physics—the angle of the sun during these months means those UV-B rays we need just don't reach us effectively. Add in our indoor lifestyles, and you've got a recipe for widespread deficiency.

More Than Just Bones: Why This Matters

Yes, vitamin D is famous for keeping bones strong—preventing rickets in children and osteomalacia in adults. But emerging research suggests its influence extends far beyond our skeletal system. Low levels have been linked to:

• Increased susceptibility to respiratory infections

• Mood changes and seasonal affective disorder

• Muscle weakness and increased fall risk in older adults

• Potential impacts on immune system function

The good news? This is one health issue with a straightforward solution.

Your Winter Wellness Action Plan

1. Take a Daily Supplement The government now recommends that Everyone in the UK is advised to take a daily supplement containing 10 micrograms (400 international units) of vitamin D during the autumn and winter months. That's everyone—not just those at high risk.

2. Eat Vitamin D-Rich Foods While it's difficult to get enough from diet alone, these foods can help:

• Oily fish (salmon, mackerel, sardines)

• Egg yolks

• Fortified foods like some breakfast cereals and spreads

• Mushrooms exposed to UV light

3. Consider Year-Round Supplementation If You're High Risk You should consider taking vitamin D supplements throughout the year if you:

• Have darker skin

• Rarely go outdoors

• Usually wear clothes that cover most of your skin

• Live in a care home

4. Get Tested If You're Concerned Symptoms of deficiency can be vague—fatigue, bone pain, muscle weakness, or mood changes. If you're experiencing these, especially during winter, it might be worth checking your levels.

The Regional Divide

Interestingly, where you live in the UK matters. Nearly one third of study participants living in Edinburgh and Glasgow recorded low vitamin D levels in winter, while southern UK residents, from comparatively higher socio-economic regions, had less winter deficiency. If you're in Scotland or Northern England, you might need to be extra vigilant about supplementation.

Making It Work for You

The key is consistency. Pop that vitamin D supplement next to your toothbrush or coffee maker—somewhere you'll see it daily. And remember, more isn't always better. Stick to the recommended dose unless a healthcare professional advises otherwise.

As we embrace the reality of shorter days and longer nights, taking care of our vitamin D levels is one simple way we can support our bodies through the winter months. It's not about fighting the British weather—it's about working with what we've got.

Concerned about your vitamin D levels or experiencing symptoms of deficiency? The Online GP offers convenient consultations to discuss your health concerns and arrange appropriate testing if needed. Simply message us on WhatsApp to book your appointment—it's that easy.