Vitamin D from Mushrooms, Sun, or Supplements?

Today's Blog--
like
tweet
+1

Years ago, it was shown that vitamin D isn’t just the sunshine vitamin for us, but for mushrooms as well. You take some mushrooms, put them under a sun lamp for an hour, and they’ll make vitamin D just like we do lounging at the pool.

Unfortunately most mushrooms you buy at the store don’t have any vitamin D because they’re grown in the dark, but now there are sun-bathed varieties on the market that boast significant levels. Some mushrooms grown out in the wild have vitamin D as well, but only about 12% of one’s recommended daily allowance per cup.

Is the vitamin D in mushrooms bioavailable? In 2008 there was a case report of a dark skinned individual living in England in the winter who–like the other 9 out of 10 South Asians living in the UK–was vitamin D deficient. His physician prescribed a vitamin D supplement, but after doing his own research this patient decided to self-treat. He bought a UV bulb from a local hardware shop and proceeded to shine it directly onto 2 cups of regular mushrooms a day before stir-frying and consuming them. He repeated this on a daily basis for 3 months, and indeed his vitamin D levels shot up and he was cured.  So it’s reasonable to assume that such mushrooms may be able to provide a source of vitamin D for those at risk for deficiency. This was just one person though, so further studies were necessary, and finally those studies have been done.

In my 5-min video Is Vitamin D3 Better Than D2? I profile a study entitled Bioavailability of Vitamin D from Ultraviolet Light Irradiated Button Mushrooms in Healthy Adults Deficient in Serum 25-Hydroxyvitamin D: A Randomized Controlled Trial. The mushrooms were compared to vitamin D supplements and placebo, and both the mushrooms and the supplements were equally effective in raising vitamin D levels compared to the placebo.

The type of D made by mushrooms is vitamin D2, which is typically derived from yeast and is the form traditionally prescribed by doctors to cure D deficiency. Most supplements, though, are D3, which is the type found in plants and animals, typically derived from sheep’s wool. Back in 2008 it was established that vitamin D2 was as effective as D3 in maintaining one’s vitamin D levels at standard daily dosing levels. As you can see in the video, whether folks were given D3, D2, or a combo of half D3 and D2, it didn’t seem to matter much in terms of improving vitamin D levels in the bloodstream. But that was 5 years ago–what’s the update? Is vitamin D2 better than vitamin D3? It depends how you take it and what your starting levels are. Watch my video Is Vitamin D3 Better Than D2? for the latest details.

Here are my vitamin D recommendations for those in the northern hemisphere:

  • Below approximately 30° latitude (south of Los Angeles/Dallas/Atlanta/Cairo)
    • 15-30 minutes of midday sun (15 for those with lighter skin; 30 for those with darker skin)
    • or 2,000 IU supplemental vitamin D daily
  • Between 30° latitude (sample cities above) & 40°latitude (Portland/Chicago/Boston/Rome/Beijing)
    • From February through November
      • 15-30 minutes of midday sun (15 for those with lighter skin; 30 for those with darker skin)
      • or 2,000 IU supplemental vitamin D daily
    • From December through January
      • 2,000 IU supplemental vitamin D daily
  • Between 40° latitude (sample cities above) & 50° latitude (Edmonton/London/Berlin/Moscow)
    • From March through October
      • 15-30 minutes of midday sun (15 for those with lighter skin; 30 for those with darker skin)
      • or 2,000 IU supplemental vitamin D daily
    • From November through February
      • 2,000 IU supplemental vitamin D daily
  • Above approximately 50° latitude (north of Edmonton/London/Berlin/Moscow)
    • From April through September (or even briefer above 60°latitude (Anchorage/Stockholm)
      • 15-30 minutes of midday sun (15 for those with lighter skin; 30 for those with darker skin)
      • or 2,000 IU supplemental vitamin D daily
    • From October through March (or even longer above 60°latitude (Anchorage/Stockholm)
      • 2,000 IU supplemental vitamin D daily

That’s not what the Institute of Medicine says though. I justify my recommendation in this video series:

What about tanning beds? See Vitamin D Pills vs. Tanning Beds.

I also recommend to Take Vitamin D Supplements With Meals.

I still think people should eat mushrooms though! For starters, see:

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my videos for free by clicking here and watch my full 2012 – 2014 presentations Uprooting the Leading Causes of Death, More than an Apple a Day, and From Table to Able.

Image credit: Vik Nanda/Flickr

Don't miss out on life-saving nutrition information!
Subscribe for free and get the latest in nutrition research delivered straight to your inbox!
  • Mariannick

    What would be your recommendations for children ?

  • Steve

    Hi Doc,

    For those of us with Sarcoidosis and that have Vitamin D dysregulation, supplementing could be a big problem – as I am now finding out. Symptoms get worse.

    Steve

  • Barbara

    what about those of us who have had skin cancers – do you think we should still be in the sun every day?

  • PGYx

    Literature and clinical experience demonstrate that vitamins D2 and D3 raise serum levels equally well. However, with D2 levels quickly drop once supplementation ceases. Levels raised with Vitamin D3 supplementation remain in the normal range longer. In addition vitamins D2 and D3 have *slightly* different metabolic pathway end points and D2 binds less well to vitamin D receptors. On balance, I recommend D3 to my patients. If they must use D2 (for financial reasons — it’s covered by insurance since it’s a drug) I switch them to lower dose D3 after the D2 course and emphasize the need for them to keep taking it with their largest meal of the day to facilitate absorption (see Cleveland Clinic osteoarthritis clinic study published ~2 years ago). During the sunny season I recommend limb exposure to sunlight (hat/sunscreen for more chronically exposed face and shoulders).

  • Markus

    Midday sun is the strongest/most dangerous. Wouldn’t it be safer to get exposure earlier/later in the day, maybe for longer then, or is the sun not producing the required spectrum at those times? You did not specify how many days/week or did you mean daily?

    • df g

      You can only make vitamin D when your shadow is shorter than you are. This has to do with the ultraviolet spectrum. PLM

  • Ben

    Hi Doc,

    What percentage of the skin should be exposed to sun in these recommendations? Is short sleeves enough?
    Thanks!

  • BPCveg

    Can you please write an article justifying your recommendation that we take DHA oil? Please.

    • Thea

      I second this! I share Dr. Greger’s nutrition recommendations with lots of people. I understand all of them except the DHA oil one. It just doesn’t seem like there is enough evidence to support such a recommendation. I was taken by a talk I saw not too long ago by (I think) Dr. McDougall who said something like: it is true that our bodies don’t convert much omega 3 from flaxseed and other plant sources, but it does make all that we need. *If* that is so, then I don’t understand Dr. Greger’s recommendation.

      Thanks BPCveg for being the first to voice my interest too.

      • nc54

        Dr. Gregor’s recommendation to my knowledge is, take DHA as an insurance policy if you have the means, and if one is pregnant he then highly recommends supplementation. A lot of it depends on how good one’s diet is. If one is consuming a lot of Omega 6 rich foods, like peanut butter and nuts and such, then they would most likely benefit from DHA oil in their diet. But if one had an ideal diet, with a 1 -1 ratio of 6 and 3 omegas, then DHA oil would probably be unnecessary. But in the case of pregnancy, probably best to err on the side of caution and take the oil no matter how good your diet is.

  • Tony

    I was just reading an article on diatomaceous earth and it seems too good to be true, and wondered what your views were on this?

    http://www.naturalnews.com/039326_diatomaceous_earth_detox_mercury.html

    • jp

      Hi Tony,
      Reading the article..interesting..Hey just stumbled on something so interesting i made a website:
      http://www.joynewearth.com
      jp

  • Daniel

    Hi!
    I live in France and I’d like to know if you could recommend me a website where I can purchase safe, good Vitamin D supplements?
    Thanks in advance,
    Daniel

  • Butterflies Katz

    I don’t like to get midday sun, but morning and evening because the sun is too burning during the midday in summer, you don’t really say how long for non-midday sun exposure.

    • imdhreeves

      The midday sun is recommended because the atmosphere at other times will block the rays that we need to make Vit D. The sunburn rays will get through though so morning and evening sun will only burn not make D for us.

  • http://www.dietkart.com/ ✪ DietKart.com ✪

    Unfortunately most mushrooms you buy at the store don’t have any vitamin D Some mushrooms grown out in the wild have vitamin D as well, but only about 12% of one’s recommended daily allowance per cup. i am unable to understand the fact that —-You can only make vitamin D when your shadow is shorter than you are…is it true ?

    Thanks,
    http://www.dietkart.com

    • Thea

      DietKart: “i am unable to understand the fact that —-You can only make vitamin D when your shadow is shorter than you are…is it true ?”

      I am guessing that this bit of advice came from the issue that you can only make enough vitamin D to satisfy your needs in say 20 minutes of time if you are in the noon day sun. (At which point you would have a shorter shadow.)

      There are several videos on this site about vitamin D. Dr. Greger also addresses how much sun and at what time of day for creating vitamin D by where you live in the world on the following page:

      http://nutritionfacts.org/2011/09/12/dr-gregers-2011-optimum-nutrition-recommendations/