The dangers of vitamin D

Learning about vitamin D in medical school we focused on it’s role in maintaining healthy bones. I now know that this humble vitamin is involved in many many more body processes with vitamin D receptors found in nearly all cells in the body including the brain. And, just like Goldilocks and the 3 bears, there can’t be too much or too little….

What does vitamin D do?

Reviewing the science and evidence on how vitamin D impacts health, it’s mainly responsible for maintaining healthy bones and a healthy immune system but many other health affects have been studied. It’s also important to note that for vitamin D to do it’s work it needs magnesium and vitamin K. This means, for example, that vitamin D will not function properly without adequate magnesium in our body.

Bones. Vitamin D helps with aborption of calcium from our diet as well as bone formation and remodeling. Read more about healthy bones here. Without enough vitamin D our children’s bones become soft and weak. This makes long bones bendy and results in the typical bowed legs of rickets.

Immunity. Vitamin D acts as an immune modulator. This means that it stimulates certain immune cells to work whilst inhibiting others. It helps our body effectively fight infections without an overactive response. This is where it may play a role in coronavirus. It could theoretically support the immune cells to help prevent infection and then also inhibit the immune response (cytokine storm) that is implicated in the severe respiratory disease patients are developing. We don’t know enough yet to for it to be a standard recommend treatment but to me it seems reasonable to at least ensure you’re not deficient.

Acute Respiratory Tract Infections (ARTI’s). There have been multiple studies including meta-analyses looking at vitamin D supplementation to prevent pneumonia. Meta-analyses are studies that effectively study other studies by analysing all the data together to maximise the information and accuracy of result. The studies I reviewed concluded it is safe to supplement with vitamin D and could be protective especially if patients were deficient.

Asthma. There is conflicting data regarding vitamin D improving eczema and asthma. There is some evidence though that if children have adequate levels when very young, they’re less likely to develop asthma when older. It’s impact on the immune system is thought to explain this.

Blood sugar balance. Vitamin D is thought to improve control of blood sugar levels by improving our sensitivity to insulin. Insulin is the hormone that regulates blood sugar levels by functioning like a key, helping sugar (glucose) enter cells where it can be used for energy or stored.

Other. Vitamin D deficiency has been associated with obesity, depression, thyroid disease and diabetes. As well as cardiovascular disease and cancers in adults. It’s important to note that an association doesn’t always mean that the low vitamin D levels are causing the illness. But I definitely think that it’s important to check your child’s vitamin D level if they have any of these conditions.

How common is vitamin D deficiency in kids?

Different ages and population groups have different risks for vitamin D deficiency so there’s a huge variation. It has been estimated though that the overall prevalence in kids in the US and Australia is around 15%. I see a lot more than this in my practice. This may be surprising to some considering Australia has a lot of sunshine.

Vitamin D, also known as the “sunshine vitamin”, is mainly produced in our bodies with UVB exposure. But how much? What about sunscreen? The answer depends on the time of year and where you live. In Sydney Australia it can mean 5 minutes in summer and up to an hour in winter. I’ll write a more detailed blog about this soon.

Is your child deficient?

Unless your child’s levels are extremely low and calcium levels have also been affected it’s hard to clinically detect a deficiency unless you do a blood test. There are certain situations that make me suspicious though. If you’d like to read more about clues and what to do, hold tight because I’ve a really helpful ebook that will launch soon.

Can you have too much vitamin D?

Yes! This is why it’s important to know if you need to give your child a supplement and also how much. Unlike some of the water soluble vitamins, vitamin D isn’t just excreted when you have too much. You know when your wee becomes really yellow after having a multivitamin? Well this is usually from water soluble vitamins especially vitamin B2. Vitamin D actually gets stored in your body. Too much can cause hypercalcaemia (too much calcium) and many problems including bone disease, headaches, vomiting, diarrhoea, heart disease and kidney disease. This means that more is definitely not always better.

So, as always, please be careful with any supplements for your children and find a healthcare provider to safely guide you.

If you’ve found this interesting or helpful please share it and sign up for my newsletter 🙂