Anecdotally, it was a game changer for me personally. I got less sick during the winter, and my overall wellbeing improved greatly.
A word of advice, increase Vitamin K intake aswell. Vitamin D helps calcium absorption, but Vitamin K directs it to where it needs to go (skeleton).
I know it sounds downright crazy, but it's possible that someone who's studied medicine and practiced it for years, actually knows better than random anonymous forum users.
As the link in the OP actually denotes, no, that's not always the case.
Bodybuilders and performance trainers - as well as Soviet Union sports scientists - have known for decades that Vitamin D supplementation is vital. This has been rejected by a significant number of general practitioners and other medical experts who are and were anti-supplement simply out of rote thinking.
Yes, people should be tested for their levels. But this simply isn't feasible for poor people, and telling them to get serum tests for Vitamin D before taking a lower-bound amount of the cheap supplement from the grocery store is ridiculous.
http://www.rollingstone.com/sports/news/russia-banned-from-2...
It is always possible to arrive at a correct conclusion through entirely incorrect reasoning.
Or, as the saying goes, a broken clock is right twice a day.
Homeopathy is crap. But bodybuilding/powerlifting/athletic training often finds the answers well ahead of peer-reviewed science.
A fruit or vegetable that have traveled thousand of miles before being delivered to you has almost no vitamins left in it and probably didn't have much to start with considering soil depletion.
I believe (emphasis on believe) that supplementation is necessary even if you "eat right".
Truth be told, doctors still don't know much about IBS and/or Crohn's. Or even conditions like rosacea and/or dermatitis. Mark my words, better gut flora/microbiome will be the cure for these conditions in the near future and doctors will contest this up until the evidence is too loud to ignore.
For instance, overdose quantities may be different among the various vitamers of a specific vitamin. Your physician will advise you not to supplement ADEK because people have overdosed on retinol or ergocalciferol, whereas you can eat carotene until you literally turn orange, and 15-30 minutes of daily midday sunlight can make 10000 to 20000 IU each time.
The danger of vitamin D oversupply (even as cholecalciferol) is calcium related, which is why you have to balance it with vitamin K (as menatetrenone), but it's called vitamin K from the German for "clotting factor", so then your doctor worries about clots. But vitamin E (as RRR-alpha-tocopherol) is also an anticoagulant. It's almost as if you have to consider every vitamin as just one part of a balanced system of nutrition...
So in order to give you good advice, your doctor would have to have detailed and intimate knowledge of your current nutritional state and your physiology, but we only have 15 minutes and I don't want a malpractice suit for giving you the wrong advice, so just f' it and give 'em the boilerplate: "You don't need to supplement. Just eat a balanced diet with plenty of dark green vegetables, and get some exercise."
So there you go. I just saved you a copay, unless your particular physician has an interest in nutrition-based medicine.
Don't get your vitamins from the corner pharmacy or the grocery store. Most of them will use the cheapest chemical that technically qualifies as a particular vitamin. You need specific vitamers if you intend to exceed the general recommendations. Do your own research, and remember that you can damage your own body by doing something stupid with it. If you consult a physician, make sure they have enough training and education to be credible with respect to nutrition and biochemistry before you fork over money for an office visit. You can read the same articles and papers that they read, if you are motivated enough to do so.
If you want to safely increase vitamin K, just eat more dark green vegetables like spinach. There's no need to overdo it with K or it could be a regrettable error.
You may not like the taste, but trying it is an interesting experiment.
Natto is not "normal". It is an acquired taste. The acquisition of said taste is a difficult, nauseating, and extremely stinky path. Besides that, most of the vitamin K from natto is as MK-7.
Animal-sourced vitamin K is mostly menatetrenone (aka menaquinone MK-4) whereas vitamin K from fermentation bacteria is various lengths of menaquinone, of which only MK-4 and MK-7 have good vitamin K activity in humans, and the MK-4 form is usually nearly absent. Plant-sourced K is as phylloquinone, which has to be converted to menatetrenone in the body.
So also-good sources are egg yolks from free-ranging, pastured laying hens and butter from free-ranging, pastured dairy cows. Basically, you need to eat parts of animals that were raised by traditional, non-battery farming, particularly the livers and adipose tissue. Poultry animals such as geese, chickens, and ducks are good for this. Apparently, the oil from rendered emu fat is also high in vitamin K.
Cheeses have some MK-4 from the milk and some MK-7 from the bacteria, but a lot of their K is in less easily assimilated forms. That's probably good enough unless you have some rare and nigh-undetectable enzymatic deficiency that interferes with conversion of MK-9 to MK-4, or something.
I suppose that if you force-fed some geese a bunch of natto, and then mashed up their livers into a paste, that would be a great vitamin K pate. I think I'd rather just swallow a pill.
Most pills/drops you would prefer over foie gras are mostly made from Natto (MK-7) btw.. there are some supplements with MK-4 but those are rare and quite expensive.
Foie gras is nauseating for a completely different reason than natto. As actual food goes, I'd rather eat the pastured eggs and butter, even though they are also rare and expensive in US supermarkets.
It doesn't help that the supplement industry is loaded to the rafters with hucksters and scammers, but you can get a year's supply of pills labeled as 5 mg MK-4 for $90. It'd be hard to tell whether that's really what's in them without engaging a testing lab at additional expense.
Just out of curiosity, did you work out regularly in a gym before taking those pills?
I think I will talk to my doctor about trying some Vitamin D supplementation in the next months. Generally I try to avoid supplements, but in this case I don't know what else to try.
Remember to keep them on during the _daytime_ only, though, to keep your body clock on the appropriate schedule!
Some people (including me) find that they stay indoors most of the time in the winter. Doing your workout outside gets you out there, which gives you not only sunlight (speaking of Vitamin D) but also a change of scenery that can cut down on cabin fever.
With the proper gear, the cold is tolerable (except maybe in extreme climates). And, especially if the exercise is vigorous, it's more tolerable being outdoors in the cold than it would be if you just went stood or sat around outside.
Just take half a pound of spinach and boil it, when you eat it, it'll be about the size of a medium bowl. That will be about 50 calories and contain 1200% of your daily vitamin K needed!!
It really isn't that simple. One issue is that it doesn't matter how much is in spinach if you don't absorb it.
>...Circulating phylloquinone levels after spinach with and without butter were substantially lower (7.5- and 24.3-fold respectively) than those after taking the pharmaceutical concentrate. Moreover, the absorption of phylloquinone from the vegetables was 1.5 times slower than from Konakion.
https://www.ncbi.nlm.nih.gov/pubmed/8813897
And while those vegetables will get you some K1, they won't get you K2 which is important for how calcium is handled in the body.
>...We examined whether dietary intake of phylloquinone (vitamin K-1) and menaquinone (vitamin K-2) were related to aortic calcification and coronary heart disease (CHD) in the population-based Rotterdam Study.
>...The relative risk (RR) of CHD mortality was reduced in the mid and upper tertiles of dietary menaquinone compared to the lower tertile [RR = 0.73 (95% CI: 0.45, 1.17) and 0.43 (0.24, 0.77), respectively]. Intake of menaquinone was also inversely related to all-cause mortality [RR = 0.91 (0.75, 1.09) and 0.74 (0.59, 0.92), respectively] and severe aortic calcification [odds ratio of 0.71 (0.50, 1.00) and 0.48 (0.32, 0.71), respectively]. Phylloquinone intake was not related to any of the outcomes. These findings suggest that an adequate intake of menaquinone could be important for CHD prevention.
Just a counter-point. Vitamin D didn't help me with SAD. SAD seems only addressed for me by a proper full spectrum lamp for 30 minutes a day in the winter.
They are important cofactor for many proteins, including one called osteocalcin, needed for bone calcification.
Search on that page for: "Skeleton and Bone Metabolism". K1 and K2 work differently. We know a lot but there is still a lot more we don't know. Hell, looks like even different versions of K2 (from MK-4 to MK-13) works for different stuff in body. Only because MK-7 stays in blood for longer than MK-4 doesn't mean that it better. It could also mean that body is better in utilizing MK-4, or even that it's using it for different stuff.
More here: https://chrismasterjohnphd.com/2016/12/03/start-here-for-vit...
Here is a university page with information:
http://www.umm.edu/health/medical/altmed/supplement/vitamin-...
They collect and analyze available research, and the result of that process is their product (in the form of guides etc).
Personally I don't know better source with information about different supplements than examine.com, more how they are working here: https://examine.com/about/ If you know better source point it to me, please. This university page you provided is short and old.
Just one question: what's wrong with using dotcom domain?
i guess to respond to your question: most biomedical research today is eminating from universities and university-affiliated entites. page for page, i generally wouldn't expect a .com web site -- the majority of which are probably just attempting to generate advertising revenue -- to be on par in terms of accuracy etc with a .edu site. generally, I've found one of the best ways to improve the signal-to-noise ratio is to filter to a specific set of domains (e.g., ,edu, .gov) when searching online.