High dose vitamin d and breastfeeding

(9 Posts)
Cityzen74 Thu 30-Jul-20 21:22:35

I have been diagnosed with low vitamin d so have been prescribed a high dose course to take once a week for 8 weeks. I am still breastfeeding and of course it says on the info sheet not suitable for use if you are pregnant or breastfeeding. My DS only feeds at night now so hardly at all but am worried about taking the dose. He is slightly deficient in vitamin d too (although much improved from the last time he was tested) so I don’t know if it might benefit him too. I will speak to the pharmacist but has anyone been in this situation with any advice? Thanks smile

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dementedpixie Thu 30-Jul-20 21:24:40

How high is the dose?

Pinkflipflop85 Thu 30-Jul-20 21:28:38

I'm on a high dose prescribed by the gp and she didn't seem concerned about me breastfeeding.

If in doubt the breastfeeding network is always a good place to go for advice regarding medicines/supplements and feeding.

Cityzen74 Thu 30-Jul-20 22:33:49

@dementedpixie the dose is 20,000 (units?). Must be 10000 per tablet.

@Pinkflipflop85 that is interesting that your GP isn’t concerned about you breastfeeding and taking a higher dose. I didn’t think to mention it as I am only feeding at night and I was at work when the dr rang. I’ve had a look at the breastfeeding network info about it and they say it is probably ok but to watch in case DS has signs of being overdosed such as confusion nausea weight loss etc. I wonder if taking half the dose might be ok? I think I’d better speak to the GP again. Thanks for your comments both

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dementedpixie Thu 30-Jul-20 22:45:26

20,000IU is 500ug of vitamin D. Normally daily maximum would be 100ug but you are only taking that dose once per week so you wouldn't be exceeding the weekly maximum limit which would be 700ug.

Bettertobehealthy Thu 30-Jul-20 23:21:25

Hi Cityzen74,
I hope this explanation is useful to you. It should help you decide on the best course of action for your son.

Most mothers in the UK, supply breast milk with approx 25 IU of vitamin D per litre of milk. Current recommendations are for babies to receive 400 IU Vit D per day.

For that reason UK recommendations are that "Exclusively Breast Fed" babies are supplemented with about 375 IU Vit D drops daily from a few days after birth. ( Please note .... formula milk is supplemented with 400 IU vitamin D per litre ... it can make up for the deficiency of mothers milk with respect to vitamin D)

The reason that UK mothers breast milk is deficient , is that overwhelmingly, UK mothers are deficient or insufficient in Vit D.

When the mother takes a supplement of Vitamin D a proportion of that supplement goes into the milk. SO, lets say you are taking about 6000 IU per day , then your milk will contain about 400 IU per litre. Which is an adequate amount for baby. It is the same as found in formula milk. So is not harmful. That level of Vit D in breast milk is in fact what would be found in your milk , if you lived just as our ancestors did, in sunny climates , outside , in sunshine making Vitamin D , every day of the year. However, in high latitude , western countries , such as the UK , we cannot make those quantities of vitamin D in our skin from sunshine. Food , such as meat and animal products does have some of the vitamin D that we need. But usually not nearly enough . That is why breast milk is so deficient at 25 IU and not 400 IU per litre.

When you take a supplement of VitD3 , ( that is cholecalciferol ) , then some of that cholecalciferol is transferred to your milk. A dose of cholecalciferol, will result in your milks concentration increasing. After a short time , say three days , the cholecalciferol that you have taken is converted in your liver to calcidiol, a modified version of vitamin D , (technically ...it has had one hydroxylation ) . Calcidiol , is what is measured in your blood , and is called your vitamin D "level " . Calcidiol is not transferred in your milk. ONLY cholecalciferol, the original vitamin D3 supplement is transferred in your milk. That is a very important point to grasp.

Depending upon your supplementation regime , that you have been prescribed, daily , weekly or monthly , will determine what level of VitD3 (cholecalciferol )is in your milk. IF you take 40,000 per week, once every 7 days , then you will have a "pulse" of cholecalciferol , at high concentration for the first 3 days. meanwhile your liver will transform the cholecalciferol , at about 50% per day , i.e half life 24 hours. Such that after 3 days it is nearly all calcidiol, and there is not much cholecalciferol VitD3 to transfer in your milk. On the other hand , if you take 6000 IU per day , daily , then the concentration of VitD3 in your milk will not vary. That is 42,000 IU per week just about equivalent to a weekly dose of 40,000 IU.

The obvious conclusion , from all this explanation , is that you would be better to take a daily supplement , rather than a weekly supplement . Up to 6000 IU per day , will only increase your vitD3 level in your milk up to those levels found in formula milk.

It is probable that you have been advised to supplement baby with drops ? if he was found to be deficient in Vit D.

Have a look at the Vitamin D Association website,
www.vitamindassociation.org/ On the front page you will see a lecture , by Prof Hollis , a world expert on Vit D, pregancy and lactation.

Hope that was useful' if you need any more information, just get back to me.

best of luck


Cityzen74 Fri 31-Jul-20 11:18:03

@Bettertobehealthy thanks so much for that brilliant detailed advice. I appreciate it so much smile. I would feel much better taking smaller amounts daily as opposed to the huge amount every week. I will speak to my GP about it. I will look at the link you sent too.

Yes I need to give my DS vitamin d but I am giving it to him with multivitamins which dr says is fine. He had the high dose which brought his levels up from 20 to nearly normal. Dr said as long as I carry on with multivitamins they don’t need to monitor him anymore.

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Cityzen74 Fri 31-Jul-20 11:20:06

Thank you @dementedpixie. I find the different measurement units very confusing smile

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Cityzen74 Fri 31-Jul-20 17:16:29

Just wanted to say thank you to everyone. Spoke to GP who prescribed a daily dose instead smile

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