I happen to have a gene mutation that makes methylation of B12 inefficient. I never did well in chemistry or biology for that matter, but my limited understanding is that methylation is necessary for it to be useful.

It turns out that you can buy methylated B12 called methylcobalamin. The more common form is cyanocobalamin, and is not very useful for people like myself.

That is my understanding, if anyone here knows better or more, please correct me.

Thanks for this added information. I discovered the same thing, with another family member where Methylcobalamin worked wonders and Cyanocobalamin didn't.

One thing I would add is that Methylcobalamin needs to be injected to work best. If people do not have your gene mutation, they are better off taking Cyanocobalamin.

PS: Whenever someone in family has major health issue which no one can get handle on - they reach out to me. My lifelong dream has been to cure Cancer using AI. Just started working on that.

You can take methylcobalamin sublingually. Absorption is fine, according to my blood results.

I'd be interested to see your approach and what you've done so far on the Cancer/AI front. Do you have links to anything online?

I thought the injection was typically hydroxocobalamin. Has this changed?

Yep, they are and also the best form. Extremely unstable in capsules and oral supplements though.

Methylcobalamin isn't very effective orally. However someone with a gene mutation doesn't have any choices.

It actually is quite effective, much like cyanocobalamin. (The usual form in supplements.) Needs just slightly higher dosage than hydroxocobalamin.

Typically it is further up the methylation pathway. You might need methyltetrahydrofolate (5-MTHR, brand names Metafolin and Deplin) supplementation combined with methyl-B12.

Does the typical B12 blood test test for this? Or do you have normal levels even without supplementing methylcobalamin?

True, cyanocobalamin for people like you won't work.

Although consuming just methylcobalamin leaves out adenosylcobalamin.

Yet taking too much B12 increases risk for lung cancer. [1] [2]

[1]: http://ascopubs.org/doi/abs/10.1200/JCO.2017.72.7735

[2]: http://edition.cnn.com/2017/08/22/health/vitamin-b6-b12-lung...

It's difficult to determine whether there is a selection bias. Many people who smoke, take Vitamin B12 supplements.

Anyways it's a good idea to not overdo these supplements.

It's really hard to be confident in a study that finds an effect in men and not women, with no plausible explanation for the difference.

Because of impaired kidney function, I get my vitamin D levels monitored every month. Yes supplements can take 2-3 months to increase the levels. The sun actually works pretty good if you can stay outside 15 minutes in noon sun. But that's difficult in the winter months.

I've read varying reports of how much sun you need to generate a day's supply of vitamin D, but rarely do they mention how much skin needs to be exposed.

Face only? Face and arms? Entire upper body? Entire body?

Is there some online resource for this with time of year and latitude corrections? I imagine there's quite a difference between vitamin D production in noon sun in Fairbanks Alaska versus Miami Florida.

I did some searching...

"John Jacob Cannell, MD, executive director of The Vitamin D Council, notes that the skin makes 10,000 IU of vitamin D after 30 minutes of full-body sun exposure. He suggests that 10,000 IU of vitamin D is not toxic."

https://www.webmd.com/osteoporosis/features/the-truth-about-...

Except that 10000 IU is mostly localized in skin and released a bit slower.

For it, my face and arms are exposed. I walk in the bay area sun for 15 minutes after lunch. Doing this regularly over a month or two will boost my numbers from the mid 20s to mid 30s.

Not to mention it needs to be adjusted for skin tone. The whole reason that humans have a range of skin tones is that paler skin allows for better vitamin D absorption at higher latitudes.

Depends on a lot of things as you mentioned, but also especially on your pigmentation/levels of sunburn. I'm very dark skinned, so I need a lot longer for UV rays to penetrate.

Note that in the winter months even if you're naked outside in the UK you won't get any vitamin D, the sun is too low, the latitude (about same as Alaska) too high.

Would depend on how dark your skin is.

Another big challenge in winter months is that people are so covered with warm clothes, that even going out in Sun doesn't help much.

I wonder if glass windows would block out the benefits?

Yes it does block [1]. Coincidentally I was discussing this with a co-worker last week.

[1]: http://www.sciencefocus.com/qa/can-you-absorb-vitamin-d-thro...

Ordinary window glass blocks 90% of UV-B which is needed to produce VitD.

I do remember reading years ago about a sanitarium in the late 1800's - early 1900 where the windows in the sun rooms were quartz glass.

Anecdotally, a lot of window products have built in films, coatings, or dopants that reduce UV exposure and possibly other portions of the spectrum.

I would /guess/ that pure (greenhouse?) glass, maybe not even visibly transparent, would be effective.

Both could be worth studying if someone hasn't already.

Glass itself blocks a lot of UV. Even not doped.

There exist optically transparent plastics that do not.

I've never read a recommendation for 100 nmol/L before. Previous numbers were around 50-70 nmol/L. So this seems noteworthy.

There also appears to be some evidence to support Vitamin K2 as a complement to Vitamin D supplementation, in order to reduce or prevent cardiovascular calcification.

I just want to say the b complexes are indeed super important, but recent studies indicate a potential link between overly high dosage and some types of cancers, particularly in men. So be wary of overdoing it with those 3000% dv supplements.

5-hr energy drinks have 8333% the recommended dosage!! When I saw this I threw mine away, that’s a scary amount, considering the cancer link as you said.

The occasional B vitamin overdose is unlikely to harm you. B vitamins are water soluble, so if you consume more than you need you'll just pee it out within 24 hours. And the toxic levels for most B vitamins are between 100 and 10,000 times the recommended levels.

I threw out some vitamins and energy drinks after reading about this.

https://www.theatlantic.com/health/archive/2017/08/b12-energ...

What if the increase in lung cancer was caused by more breathes being taken. It would be funny if both the “energy/metabolism” crowd and the “cancer” risk proponents were correct.

> [D and] B12. Folks, get both of these checked.

Yes, please. I'm spreading this news for years. Many are deficient in both. B12 has a name for being low in veg*ans, while that is true many omnis are deficient as well.

It's good to have more papers published on "high-dose D3". But by what I read this has been know for many years.

And shun multi-AZ tablets, they provide a false sense of security. Eat loads of fresh produce and beans, that should help with most of your nutrition needs. Shun dairy and processed foods -- they kill you. Limit (or drop) meat, fish and eggs. Finally you want to eat a brazil nut every day for your selenium.

Supplement D3 and B12. Possibly (after doing your research) iodine, iron, high-DHA omega 3.

Drop meat, fish, eggs, dairy products...what's left? Vegan cuisine?

Not that it wasn't obvious, but you should still disclose your bias.

Good luck with your vegan diet. I hope that beans and veggies can provide for all your nutrition needs. But better keep going to those regular doctor checkups.

> Vegan cuisine?

Yes. Let's call it plant-based. As veganism is much broad and often based on ethics. Where plant-based diets mostly based on scientific findings. Especially the whole-plant (WFPB) diet seems to have a lot of scientific backing in being the healthiest diet.

> I hope that beans and veggies can provide for all your nutrition needs.

Thanks. But this is more then well proven by studies now. And I did my checkups, only D and B12 were deficient (now fixed). I never felt healthier. See "the china study" and "the adventist studies". Also the nutritionfacts.org website/YTchannel and MicTheVegan will give you a good overview of the scientific evidence behind the health benefits of a whole plant-based diet.

> Not that it wasn't obvious, but you should still disclose your bias.

We're all biased. I'm not paid say this, or paid by big-broccolli, thus no conflict of interest :)

> Limit (or drop) meat, fish and eggs

What are you smoking?

Without being too facetious, do you have anything to contribute as to why you might think dropping meat, fish, and eggs from your diet would be detrimental?

The benefits of eliminating meat include reduced markers of inflammation within the body. Reduction of cholesterol. Changes in gut microbiome which as the emerging science is describing may have a more important impact on mood and cognition than we previously thought. Lengthening of telomeres. Oh and how about making the single most impactful change an individual can make to reduce climate change.

From my understanding of the subject the only real downside from eliminating meat or reducing it substantially is the reduction in essential B vitamins provided. This is widely recognized by those who promote a plant-based diet and the solution is to simply supplement with a super B vitamin supplement.

So what are you smoking?

Thanks for chiming in.

> the only real downside from eliminating meat or reducing it substantially is the reduction in essential B vitamins provided.

Only the B12 actually. And omnis are also often deficient. Even industrially farmed animals were deficient until they started to supplement their feed (so when eating industrial meat, you indirectly eat supplement).

The B12 deficiency in those eating plant-based is a hygiene issue: before settling in villages we ate a lot of "soil" with our food, and drank a lot of soil-run-off surface water. As the soil contains a lot of B12 and the microbes that create it (which probably can even live in our intestines).