The Wonder Vitamin

Lockdown has seen an increase in Vitamin D deficiency. 1 in 4 Australians are deficient. Adequate levels are so important for fertility and pregnancy!

Did you know that Vitamin D capsules are absorbed via the intestines and circulates in plasma bound to a vitamin D protein. Unfortunately dietary intake of vitamin D makes a small contribution to overall vitamin D status and levels due to little vitamin D occurring naturally in the food supply.

A recent research article highlighted that the largest source of vitamin D in adults is synthesis from solar radiation. 30 mins of sunlight delivers 50,000 iu of vitamin D. The best source is the sun!  

The benefits of Vitamin D:
– regulates insulin levels and secretion
– supports immune modulation
– influences fetal development
– Supports bone and calcium homeostasis
– Supports lactation
– supports endometriosis
– reduces chances of pre-eclampsia
– neonatal mortality
– reduces childhood asthma

Current guidelines recommend a vitamin D intake of 400 to 800IU for pregnant women. In Australia we recommend a dose of 1000IU per day.

In clinic, we like to see our patients Vitamin D levels at 100n/mol. If your levels are between 50-80. Go outside, soak up some sunlight!

Research article PMC 6210343. The Role of Vitamin D in Fertility and during Pregnancy and Lactation.

Signs You May Be Vitamin D Deficient

Vitamin D deficiency doesn't always come with obvious symptoms, which is part of why so many people are deficient without realising it. Some signs to watch for include:

• Persistent fatigue or low energy

• Bone or muscle aches

• Frequent illness or infections

• Low mood

• Hair loss

• Slow wound healing

• Muscle weakness

Because these symptoms overlap with so many other conditions, the only reliable way to know your vitamin D status is through a simple blood test, rather than relying on symptoms alone.

Food Sources of Vitamin D

While sunlight remains the most significant source, certain foods can offer a supporting contribution to your overall vitamin D intake:

• Oily fish, such as salmon, mackerel and sardines

• Egg yolks

• Fortified foods, including some milks, plant-based milks and cereals

• Mushrooms, particularly those exposed to UV light during growing

• Liver, in small amounts

As mentioned above, food alone typically isn't enough to maintain adequate vitamin D levels, which is why sensible sun exposure and, where needed, supplementation are usually necessary alongside a nourishing diet.

Getting Sunlight Safely

Since the sun is the best source of vitamin D, it's worth understanding how to get sunlight exposure safely. Factors that influence how much vitamin D your body produces include:

• Time of day, midday sun generally provides the most efficient UVB exposure for vitamin D synthesis

• Skin exposure, having arms, legs or back exposed (without sunscreen) allows for better synthesis than face-only exposure

• Skin tone, individuals with darker skin naturally produce less vitamin D per minute of sun exposure and may need longer exposure times

• Season and latitude, vitamin D synthesis is significantly reduced during winter months and at higher latitudes

• Sunscreen use, while essential for skin cancer prevention, sunscreen also reduces vitamin D synthesis, which is part of why balancing sun safety with adequate exposure time is important

Always balance sun exposure recommendations with skin cancer prevention guidelines, particularly in Australia's climate. Speak with your healthcare provider about what's appropriate for your skin type and circumstances.

Testing and Supplementation

If you suspect you may be deficient, a simple blood test through your GP can confirm your vitamin D levels. Based on your results, your practitioner may recommend a specific supplementation dose tailored to bring your levels back into an optimal range, particularly important if you're trying to conceive, pregnant, or breastfeeding.

It's worth noting that vitamin D is fat-soluble, meaning it can build up in the body over time, so supplementation should generally be guided by testing and professional advice rather than arbitrary self-dosing, especially at higher doses.

Frequently Asked Questions

Why is vitamin D especially important during preconception and pregnancy? Vitamin D plays a role in fetal development, immune function and reducing risks such as pre-eclampsia. Ensuring adequate levels before and during pregnancy is considered an important part of preparing the body for a healthy pregnancy outcome.

Can I get enough vitamin D through diet alone? It's very difficult. As outlined above, few foods naturally contain significant vitamin D, which is why sunlight exposure, and supplementation where needed, are usually necessary to maintain optimal levels.

How often should I get my vitamin D levels tested? This varies depending on individual circumstances, but many practitioners recommend annual testing, or more frequently if you're pregnant, breastfeeding, or actively correcting a known deficiency.

Is it possible to have too much vitamin D? Yes, though it's uncommon and generally only occurs with excessive, unsupervised high-dose supplementation over time. This is why testing and professional guidance are recommended, rather than taking very high doses without medical advice.

Does everyone need the same amount of vitamin D? No, individual needs vary based on factors such as skin tone, current levels, sun exposure, geographic location, pregnancy status, and underlying health conditions. This is why a personalised approach, guided by blood testing, tends to be far more effective than a one-size-fits-all recommendation.

Vitamin D truly earns its reputation as the "wonder vitamin," playing a role in everything from bone health to fertility and immune function. If it's been a while since you've had your levels checked, it might be worth adding to your next round of blood tests.

Amanda is the founder of Angea and has over 12 years of experience working with women to support their health journey. In addition to being a registered doctor of Chinese medicine, Amanda is a yoga teacher and founder of Mindful Pregnancy Yoga Training. Amanda offers acupuncture, Chinese herbal medicine and womb healing treatments at Angea.