Haptocorrin and B12 Absorption

[MoKayD]

I've pasted below an excerpt from a paper which described how low vitamin D levels can cause insomnia. It also discussed why low vitamin D can lead to B12 deficiency. During my many, many hours of online research I've never read anything about this, has anyone else?

Why vitamin D deficiency can lead to B12 deficiency:

Vitamin D helps make a protein in your saliva called haptocorrin. While you chew your food the haptocorrin binds B12 and accompanies it through the stomach. In the stomach vitamin D helps make a second protein, intrinsic factor, that binds to the B12 and accompanies it to a special absorption area in the small intestine. These two proteins help guarantee that we get every single B12 that comes along in our food.

[Emmers5]

I noticed comments about haptocorrin in this article sleepbunny referenced

ncbi.nlm.nih.gov/pmc/articl...

[fbirder in reply to Emmers5]

Yes, it is correct that haptocorrin in saliva is important in absorption of oral B12. But there is zero evidence that Vitamin D is specifically involved in its synthesis.

[Nackapan]

That's interesting as I was very low and had loading doses of vit d 2-3 years before b12 deficiency found. That with the menopause another known risk factor as produce less stomach acid all adds up.

All hindsight unfortunately

Hope in the current climate everyone Is topping up with vit. D !

[Parksy]

That is really interesting as I was really low in vitamin D abs despite taking supplements I’m still only at the lowest range of normal.

[Hidden]

Same here my vitd was 37 when I first had blood tests done after my accident and gp put me on high doses and told me to buy otc after my initial doses from him finished he also said to take those massive big calcium tabs,like horse tablets which I didn’t because I was wary of taking more calcium with my kidney stone history.

I do think vit d has more importance than we give it credit for,I’m presently supplementing again to keep my levels decent as I don't go out as much as I should because of lockdown and I think it would be wise as per nhs advice to supplement in winter anyway.It was after my diagnosis that I started to do private testing for my other vits and discovered as I went into things in more depth I actually had p.a x

[fbirder]

Never heard of that. Can't imagine any possible way that a Vitamin D deficiency could specifically affect those two proteins.

And I cannot find the source of your quote. Doing a google search for "Vitamin D helps make a protein in your saliva called haptocorrin." gives just one hit - your post. The same for a search of - "Why vitamin D deficiency can lead to B12 deficiency".

If it is a scientific paper then it's not listed on the internet.

[MoKayD in reply to fbirder]

I was researching vitamin deficiencies that cause insomnia when I stumbled on a website for a program called RightSleep. The person behind the program is a Dr. Gominak (who for all I know could be a charlatan.) Under the Learn tab I found this paragraph about what she claims is a link between vitamin D deficiency and B12 deficiency. I will not be buying into the program but I might start taking a vitamin D supplement.

[fbirder in reply to MoKayD]

The NHS recommend that everybody take a Vitamin D supplement during autumn and winter. And people with PA may have impaired absorption of Vitamin D from food. So it's doubly a good idea for them.

[fbirder in reply to MoKayD]

Well, hewr web site on Vitamin D is full of BS.

"It is not in our food."

"To survive the winter we must either migrate or hibernate:

Mammals, reptiles, birds, fish and insects all use D3 (cholecalciferol), to adjust their metabolism and their sleep to survive the winter."

"But most animals have a protective coating of fur feathers or scales. They still make D in their fur or feathers but they swallow their D while licking or preening."

"D goes first to the liver then into the intestines. Some of the bacteria that live in our intestine require our vitamin D to thrive. Others, the “winter bacteria”, don’t need D to survive. When we’re not passing along D during the winter the D-requiring bacteria die off and are replaced by the “winter” bacteria."

My stomach started to hurt from so much laughing at this point. So I gave up.

It is all complete and utter crap.

[MoKayD in reply to fbirder]

The website seemed like she was selling snake oil but I am always alert to any mention of B12 deficiency on the internet.

[Cherylclaire Forum Support]

I haven't heard that Vitamin D is important in either salivary haptocorrin or intrinsic factor production.

I had saliva duct strictures, which led to saliva gland infection. The ENT consultant I eventually saw agreed that this would affect haptocorrin (which binds and protects B12 as extrinsic factor from stomach acid) by reducing saliva production. While this was not the only reason for my B12 deficiency, it certainly did nothing to help. I had a procedure to widen the strictured duct using a tool with a camera and inflatable balloon -and have massage exercises to help straighten the duct.

Although I was told that this could have been a defect that I was born with, it only first became noticeable in 2012, when studying a menu in Nando's, my face suddenly started tingling in front of ears and became very swollen: Hamsterface - causing my family no end of amusement when I lowered the menu in front of me!

This was due to being very hungry; I was rapidly producing saliva (containing haptocorrin) that had no way out of the gland.

[palmier]

Perhaps vitamin D helps indirectly with b12 absorption? I think I've read that calcium is necessary for absorbing b12. Don't know much about it though.