Vitamin D levels: What should your levels be?

Vitamin D is often called the sunshine vitamin because we make it naturally when our skin is exposed to sunlight. It plays a big part in keeping us feeling well, supporting healthy bones, muscles, immunity and even mood.

But in the UK, many of us don’t get enough, especially in the darker months. If your levels are low, you might feel more tired than usual, pickup colds more easily or notice achy muscles and joints.

So, what does a “healthy” vitamin D level look like, and how can you check yours?

Why does vitamin D matter?

Vitamin D helps your body use calcium and phosphorus from food, nutrients that keep bones and teeth strong. It also helps your muscles function effectively and supports your immune system.

Low levels of vitamin D have been linked with:

• Feeling tired or low in energy

• Aches and pains in muscles or bones

• More frequent colds and infections

• Low mood, particularly in the winter

The symptoms can be quite general, and it is not always obvious that low vitamin D is the cause, which is where testing comes in.

What should your vitamin D level be?

A simple blood test will measure how much vitamin D is circulating in your system. Results are usually grouped into three ranges:

• Low / deficient – Your body doesn’t have enough vitamin D to function properly. This can affect bone strength, muscle health, immunity and even mood.

• Borderline / insufficient – You have some vitamin D, but not quite enough to be considered ideal. You may not notice obvious symptoms, but topping up your levels can help prevent future problems.

• Healthy / optimal – Your vitamin D levels are in the recommended range, meaning your body has what it needs to support strong bones, muscle function, energy and overall wellbeing.

Having a healthy level doesn’t just protect your bones; research also suggests it can also support your immune system and help reduce the risk of certain long-term conditions. Because vitamin D is hard to get consistently through food and sunlight alone, regular checks can give you peace of mind that your levels are where they should be.

How can you check your vitamin D levels?

The only way to know for sure is with a blood test. There are a few simple options:

• Through your GP if you have symptoms or risk factors

• As part of a private health check – which often includes vitamin D alongside other vitamins and minerals

• At home finger-prick kits that you send off to a lab

The test itself is quick and straightforward, and it can give you peace of mind or highlight whether you might need a supplement.

Who is most likely to have low vitamin D?

Anyone can have low vitamin D, but certain factors increase the risk:

• Spending most of your time indoors – Limited exposure to natural sunlight means your body misses out on the main source of vitamin D. This is common among people who work indoors, are housebound or spend little time outside.

• Covering your skin for cultural or personal reasons – If your skin is consistently covered, even when outdoors, sunlight can’t reach enough of it to trigger vitamin D production.

• Having a darker skin tone – Higher levels of melanin reduce the skin’s ability to produce vitamin D efficiently. This means people with darker skin may need longer in the sun to make the same amount as those with lighter skin.

• Being older – As we age, the skin becomes less effective at synthesising vitamin D, and the kidneys are less able to convert it into its active form, increasing the likelihood of deficiency.

• Eating little or no animal products – Vitamin D is found naturally in only a few foods, such as oily fish, eggs, and dairy. Vegans and those on restricted diets may struggle to get enough through food alone.

Can low vitamin D cause health problems?

Yes, over time low vitamin D can affect your bones, muscles and overall wellbeing. In children, it can affect bone development, while in adults it can make bones weaker and more prone to aches or fractures.

That’s why it’s worth checking your levels, especially if you often feel run down.

Should you take a vitamin D supplement?

Public health advice in the UK suggests that most adults take a small daily vitamin D supplement during autumn and winter, when we don’t get much sun.

Some people may benefit from a higher dose, but testing is the only way to know if you really need it. Supplements are a simple way to keep your levels topped up, especially if you’re in a higher-risk group.

Can a blood test spot low vitamin D before you notice symptoms?

A blood test can detect low vitamin D levels even when you don’t feel unwell. This is important because symptoms of deficiency, like tiredness, low mood, muscle aches or frequent colds, often develop gradually and may be easy to dismiss as just feeling run down.

By picking up low levels early, you can take simple steps to prevent problems later. For example, adjusting your diet, spending a little more time outdoors or taking a daily supplement can all make a difference. Having regular checks also helps you track whether lifestyle changes are working, giving you a clearer picture of your overall health.

How can you naturally boost vitamin D?

There are three main ways to support your vitamin D levels:

• Get safe sun exposure – In the UK, most people make enough vitamin D from daily sunlight between late March and September. Around 10 to 20 minutes outside a few times a week is often enough for many people.

• Eat vitamin D-rich foods – Include oily fish (like salmon, mackerel or sardines), red meat, eggs and fortified foods such as breakfast cereals, dairy alternatives or spreads. While food alone may not provide all you need, it can help top up levels.

• Take a supplement when needed – During the autumn and winter months, sunlight isn’t strong enough in the UK to maintain healthy levels of vitamin D. Public health advice recommends a daily supplement of 10 micrograms (400 IU) for most adults. Some people may need it all year round if they get little sun or cover their skin outdoors.

Making small, consistent changes, like combining a balanced diet with outdoor time and supplements where needed, can help you maintain healthy levels long term.

Take control with a health MOT

Checking your vitamin D levels gives you a clear picture of whether you’re getting enough of this essential nutrient. At Bluecrest Wellness, our Health MOTs can test vitamin D along with other important vitamins and minerals, giving you practical insights into your wellbeing.

You’ll receive easy-to-read results and access to a 24/7 GP helpline for a whole year. With convenient clinics across the UK, it’s a simple way to look after your health.

BOOK A PRIVATE HEALTH MOT TODAY

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0800 652 2183 to speak to one of our team.