Vitamin D Deficiency in Women: What It Looks Like (and What to Do)

This superstar nutrient plays a surprisingly major role in how you feel, contributing to quite the list of essential functions in your body. However, Vitamin D deficiency in women is pretty common. As Natalie Rouse, Registered Nutritionist and Head of Nutrition at Free Soul, explains it, “Vitamin D is essential for many biological processes, and a deficiency, whether mild or significant, can have a noticeable impact on wellbeing, impacting everything from energy and mood to hair and bone health."

Natalie goes on to explain, "While many think only of deficiency, it’s more common to have insufficient/low levels of vitamin D. Even a mild decrease affects your wellbeing. True deficiency is a greater drop in vitamin D, but even insufficiency can impact energy, mood, hair health, and bones”.

Want the full picture on what makes this nutrient so important? Check out our deep dive into the benefits of Vitamin D. But if you’re here because you suspect your levels might be low, read on for the causes, signs, and the simple ways you can support your intake.

Causes of Vitamin D deficiency in women

There’s a reason why Vitamin D deficiency in women is pretty common. Some of the biggest contributors include:

Low sunlight – We get a significant amount of our Vitamin D from UVB exposure. If you’re indoors a lot or living through the UK winter, you may not be getting enough.
Dietary gaps – Vitamin D occurs naturally in foods like oily fish, egg yolks, and fortified products (like plant-based milks) but many women don’t get enough from diet alone.
Pregnancy and breastfeeding – During these stages, Vitamin D needs increase, as some is transferred to the baby.
Age – As we get older, the body’s ability to convert Vitamin D into its active form decreases

“What’s often overlooked is how these factors can overlap,” says Natalie. “For example, a busy working mum may not have the chance to spend much time outdoors, have higher nutritional needs due to pregnancy or breastfeeding, and be too stretched to focus on diet. It all adds up, making it easy for a deficiency to creep in unnoticed”.

Signs of Vitamin D deficiency in women

Many people aren’t aware that their levels are low, Vitamin D deficiency in women symptoms to look out for:

Tiredness without a cause

Feeling wiped out, even when you’re getting enough sleep, is a common sign of a deficiency. Vitamin D helps regulate neurotransmitters and may contribute to energy metabolism, so low levels can leave you feeling constantly fatigued.

Muscle fatigue

Unexplained heaviness or weakness, especially in the arms and legs, could be a warning sign. Vitamin D is needed for muscle function, so a deficiency can often show up here first.

Low mood

If you’ve been feeling a bit off or unusually down, a lack of Vitamin D could be part of the picture. It helps support serotonin and dopamine production, two key neurotransmitters for mood regulation.

Aching bones

Vitamin D is required for your body to be able to absorb calcium properly. Without it, bones can feel sore or achey, without obvious injury.

Hair shedding

Excess hair in your brush or shower drain? It could be one of the side effects of Vitamin D deficiency in women. Vitamin D supports hair follicle health, and low levels have been linked to an increase in shedding.

Frequent illness

Picking up every bug that’s going around? Vitamin D contributes to your immune defence, so a deficiency can make you more vulnerable to colds and infections.

“What’s tricky is that these symptoms are subtle and are often brushed off as being caused by tiredness or stress,” says Natalie. “But if you’re checking several off the list at any given time, it’s worth checking your levels.”

Simple ways to support your Vitamin D levels

So, how do you keep your Vitamin D levels where they need to be? Here are the best ways

Get enough sunlight

Your skin makes Vitamin D when exposed to UVB rays, which is why it gets the nickname “the sunshine vitamin”. In the summer time (when the weather is high) even 10-20 minutes outside, with your face and arms exposed can make a difference. In the winter? Not so easy.

Grab time in the daylight when you can, and if you want to interpret this as a sign you need a January winter sun getaway, well, we’re certainly not going to stop you.

Eat Vitamin D-rich foods

While food can’t give you everything you need, it can help fill some of the shortfall, especially in winter. Try adding more of these to your diet:

Fatty fish (like salmon, tuna, and mackerel)
Egg yolks
Mushrooms
Fortified foods (such as plant-based milks and cereals)
Cheese
Liver

Incorporating more of these foods can naturally help you up your intake.

Consider supplementation

Even with your best efforts, it's not always possible to get enough Vitamin D through sunlight and diet, especially in the colder months. This is why supplements can be a smart choice. Vitamin D3 is the same type you make from sunlight, and it’s the most easily absorbable form.

Whether it’s mid-winter, you’re working night shifts, or you just want to cover your bases, a supplement can help maintain healthy levels. “Supplements are often necessary for most people during the UK winter,” says Natalie. “But even in summer, work and lifestyle patterns can still make it difficult to get enough from sunlight alone.”

How much Vitamin D should a woman take?

The NHS recommends an intake of 10mcg of Vitamin D per day for adults, especially during autumn and winter when sunlight is limited.

Some supplements contain a higher-strength dose of up to 100mcg (4,000 IU) – the safe upper limit advised by the NHS – to help those who struggle to maintain healthy levels through food and sunlight alone.

If you’re pregnant, breastfeeding, or have an existing medical condition, speak to your GP first and always follow the dosage on the label.

Women & Vitamin D deficiency FAQs

What are the first signs of vitamin D deficiency in women?

Common early signs include fatigue, muscle weakness, low mood, and bone pain. Some women also notice increased hair shedding or that they get sick more often.

Can Vitamin D deficiency cause hair loss in women?

Some studies have linked low Vitamin D levels to increased shedding and some hair loss conditions.

Can a Vitamin D deficiency make you feel anxious or low?

Potentially. Vitamin D helps regulate neurotransmitters like serotonin and dopamine, which help with mood regulation. Vitamin D deficiency has been linked to symptoms of anxiety and depression, though other factors often play a role too.

What is the normal Vitamin D level for women?

For most people, levels of 50 nmol/L (20 ng/mL) or above are considered sufficient. Levels below 30 nmol/L are too low and may cause deficiency symptoms.

What happens if I ignore a deficiency?

If left untreated, a Vitamin D deficiency can impact bone health, muscle strength, and immune function, and may increase the risk of more serious long-term issues.

How do I know if I need a supplement?

The UK government advises all adults to take a Vitamin D supplement during autumn and winter. It can also be a good idea year-round if you get very little sun exposure or have a high risk of deficiency.

Can you get enough vitamin D from food?

It’s difficult to meet your needs through diet alone. While foods like fatty fish, egg yolks, and fortified foods can provide some Vitamin D, most of what your body uses comes from sun exposure, which is why many people take supplements.

What’s the best form of vitamin D for women?

Vitamin D3 is the form your body makes from sunlight, and it's generally better absorbed than Vitamin D2, making it the preferred choice for supplements.