Doctor's Note

How much D should those who can’t get enough sun take? I now recommend 2,000 IU a day (see Optimum Nutrition Recommendations). That’s not what the Institute of Medicine says, though. I justify my recommendation on a two-week video series that begins with Vitamin D Recommendations Changed, and ends with Resolving the Vitamin D-Bate. What about tanning beds? See Vitamin D Pills vs. Tanning Beds. I also recommend to Take Vitamin D Supplements With Meals. What’s that bit about vitamin D and longevity? See Vitamin D and Mortality May Be a U-shaped Curve. You know I’m averse to mentioning brand names, but please feel free to leave any recommendations in the comments for cheap sources.

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

For additional context, see my blog post Vitamin D from Mushrooms, Sun, or Supplements? And be sure to check out my other videos and posts on mushrooms.

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  • cobalamin

    I’ve read somewhere that the body produces more than one Vitamin D on the skin, as in more than one photoisomer of Vitamin D; Is this true?

    • Dunno, but if you watch the Richard Weller video I cited above, you may notice that Vitamin D supplementation did not have the same effect on the heart as sun exposure.

      • cobalamin

        Thanks for the video.

        It has nothing to do with what I asked.

        The video says.. Sunshine realeases the NO(nitric oxide) from the skin. NO is a vasoladitor… it widens blood vessels and makes blood flow smoothly which is excellent however a person does need to eat leafy greens in the first place to get NO in the skin.

        Next time. Please refrain from answering questions you don’t have the answer to.

        • No need to be contrary. I felt the comment, though not a direct answer, was still pertinent, because…

          “Vitamin D supplementation did not have the same effect on the heart as sun exposure.”

          Be it multiple forms of Vit D, NO, or other processes we have yet to discover, there is plenty of room for an open mind and more research into the many ways sunlight benefits us.

  • John B

    Although I live in southern California and might get adequate vitamin D from exposure to the sun, I’m aware of the dangers of sun exposure such as skin cancer and prematurely aged skin and so I prefer to stay out of the sun and supplement with Vitamin D caps. Eating a plant-based diet just won’t allow you to get adequate vitamin D unless you eat a huge amount of mushrooms every day, so supplementing is much easier and probably cheaper considering the price of two cups of mushrooms each day.

    • Sun exposure: There’s evidently more going on in the body beyond the manufacture of Vitamin D.

      Richard Weller: Could the sun be good for your heart?

      Skin cancer risk versus the nation’s biggest killer. You do the math.

      • HemoDynamic, M.D.

        I agree! I have already seen that Ted presentation and it is fantastic what the evidence is showing. Everyone should watch that presentation. Also there is evidence that a plant based diet can reverse Gorlin Syndrome a Basal Cell Cancer genetic abnormality.
        Recently I heard that a plant based lifestyle can reverse melanoma but I cannot find the research at this time.
        Thanks Mac for your post!

        • I’m sure you caught the mention at the tail end of that talk about diet. If you want the sun to release the nitrates in your skin into your bloodstream, it behooves one to eat a diet rich in nitrate-rich plants so as to put the nitrates there in the first place.

          I expect Dr. G will enjoy reporting on that research ASAP.

    • TMR

      Vitashine D3 is a plant-based D supplement. It works well. I’ve been taking it for some time now and my D levels are excellent. Prior to this, I had a deficiency despite adequate sun exposure.

      Disclaimer: Pls note I have no financial interest or gain from mentioning this product.

    • Dan

      But two cups of mushrooms a day are great for you! LOL! The risk of skin cancer is incredibly low at 15 mins in midday sun, which is all you need is SOCAL ..The mental benefits of being in the sun also cannot be underestimated.

  • GZ

    Correct me if I’m wrong, but isn’t plant-based D3 supplementation a new and minuscule % of the overall D3 supplementation market? If so are we sure that these studies about D3 also pertain to the plant based derivatives? I don’t think I’ve ever seen a plant-based D3 supplement anywhere that wasn’t online.

    • LouiseF

      There is a vegan, Vitamin D 3 at Whole Foods. I think its made by the company, Mega Foods. It is made from mushrooms.
      I used Vitamin D2 to get my levels back to recommended levels. My boyfriend also did well with D2 as well.

      • beccadoggie10

        Vitamin D from mushrooms IS vitamin D2, not D3.

        D3 comes from the sun, and fish oil. My vitamin D3 now comes mostly from fish oil of sock-eye salmon (Vital Choice).

        In decades past, my vitamin D was from the sun and from vitamin D2, which was in comparatively low levels recommended by the American Medical Association of about 400 I.U. per day. That did NOT prevent the osteoporosis, which I have today and was diagnosed with in 2006 after first fracturing my hip. I have now twice fractured my spine.

        • cobalamin

          There is also mushrooms with D3 and lichen also has D3.

          Vitashine is a brand which get their D3 from lichen.

          • beccadoggie10

            Thank you for this information. I stand corrected with my statement.

          • cobalamin

            LOL. No you don’t. Its misleading.

            Lichen is a PLANT which contains D3.
            There is mushrooms with either D2 or D3. You jump to conclusions when you say that mushrooms only contain D2.

            This is a plant-based diet website. Fish-oil contains toxins.

  • ifyoucareenough

    What was that at the end of video? A “vegan D3”? I’ve never seen a product like that. Puzzled.

    • beccadoggie10

      Google vegan D3. A number of products come up. Never used them, but they are advertised as vegan D3. Some are at and may also be in your health food stores.

    • Country Life makes it using Vitashine D3, which is vegan since it is
      sourced from lichen. The spray bottle D3 shown in the early part of the
      video is also Vitashine D3, with the Global Health Trax label (though
      now it is Vibrant Nutraceuticals). These are the current U.S.
      distributors of Vitashine vegan D3. No, I don’t work for the company,
      just researched it since I recently bought some.

  • Expanding this, the research, D3 and Multiple Sclerosis needs to be further explored and — imho — trumpeted. D3 has proven preventative for MS. And more than that, in our personal experience, it’s also curative — as in seeing no lesions on the the last MRI, and this is 4 years out from the last attack. And symptoms are simply gone. Note that the studies done with D2 showed no benefit. But D3 — at mega doses — bears out what I say.

    Advice for MS:

    Hit up hard on mega doses of full spec oils (use pharma grade fish oils).
    Same for vit D3: huge doses, then stay at 16,000 units. (Test blood. Forget the studies of D2. D3 is “food” so pharma will ignore it. Interferon? Um. Please. Read the studies carefully.)
    Keep exercising. MS is like a vandal on a bridge you have to keep painting so it won’t rust. Everyone’s nervous system is breaking down and replacing itself everyday, anyway. You just keep ahead of it.
    Fear not. Being upset helps the vandals.
    Copaxone makes sense. And giving yourself a shot everyday talks to your unconscious: we can do this, buddy!
    Eat REALLY well. Cut sugar and flour and all prepped food.
    Don’t take the steroids.
    Be in your heart. There is no distance between us.

    • chicov

      If one has a problem with gluten but does not recognize it, D3 levels may be very hard to keep up, even with 10,000 units per day. If one is tested for gluten sensitivity it should be done while still on a gluten diet.

    • HemoDynamic, M.D.

      That’s great to hear your story. Here’s a clinical trial ending at OHSU on a very low fat Vegan Diet in March 2013

      I got to work with Dr. McDougall a bit in the initiation of some of the MS patients to a very low fat Plant Based lifestyle.

      The preliminary results I have seen are astounding so you might want to research how a very low fat Vegan diet alone has had great success in Preventing, Arresting and Reversing Multiple Sclerosis.

      • Thanks for this. Will follow it and would like more specifics. What sorts of fats do you use? We’re vegetarian but pretty much vegan, and very careful about organic, etc.,and the particular fats consumed. Keeping Omega 6 balanced, tramped down w abundant 3’s.

        • HemoDynamic, M.D.

          No added fats at all! No Oils at all! Yes no Olive Oil! You want to follow a Varied, Whole Food, Plant Based lifestyle with up to one ounce of Nuts, Seeds or Avocados daily MAX! That’s a shot glass. Dr. McDougall would say, nuts, seeds, olives and avocados only as occasional treats. And since he is the expert I would have to agree! So Flax, Chia and Walnuts are your best choices.

          • Thank you. Note — we did use oils, but are very careful with them. Nuts, seeds, important, esp flax seed.

            Early on in the MS puzzle, there was thought to be a link with mad cow. So many avenues have been explored. Scarlet fever, and other sequelae — which happened in our case. There certainly do seem to be environmental factors beyond exposure to sunlight. Pockets of MS occur. And likely it’s a collection of diseases. But arming your body as best you can — always the best defensive posture. :)

            All good wishes for your work.

    • Whatever happened to treating MS with protease inhibitors?

      • Pretty new. Haven’t seen it at the human study level yet. Looks promising, doesn’t it. Being used with HIV so…

  • jylle benson-gauss

    Reading the China Study (the excellent description of the complex vitamin D metabolic process) I noticed that excess calcium can block the release of activated D into the bloodstream. I found it interesting to note that, after Dr’s started recommending calcium supplementation for virtually everyone, within a couple of years everyone was suddenly vitamin D deficient.
    I would love to see a study of the interplay between calcium and vitamin D levels, especially since (as I understand it) calcium is a buffer when our diets are too acidic and (it seems) blood levels of calcium could rise through that mechanism without supplementation.

  • Dr. Bill Misner PhD

    Dr. Greger,

    Thank you for the interesting review on D2/D3 uptake. Apologies if this question has already been addressed…since Vitamin D levels are so important, and so many population groups are sub-normal, why not install a UV-B bulb in the bathroom where skin exposure is highest with often dose applicable? This seems to be such a simple directive that might resolve Vitamin D deficits especially in the elderly and those living in northern latitudes….

    Bill Misner PhD

    • Thea

      Dr. Bill: I’m just a lay person, but your idea sounds brilliant to me. Thanks for sharing.

    • HereHere

      The more I think about this, the more eloquent the UV B bulb seems as a solution. I may to try to find out for my bathroom, even though I’m not in a particularly high risk demographic other than being at a higher latitude (southern Canada). However, the dose seems very important. I have heard of psoriasis patients starting with 30 second treatments, and I have read that reptiles have exposure of 10-12 hours using a mostly full-spectrum bulb, where the UV B component would presumably be small. If you have some expertise in this field, could you suggest what kind of bulb (wide or narrow spectrum, or full-spectrum) and what kind of dose? Should the bulb be on a timer?

  • beccadoggie10

    All that I know is that I just accidentally fractured another spine in my lumbar region over the course of 10.5 months. Most of my calcium and other nutrients come from food, but with some supplementation (through Andrew Weil, M.D.). I take 2,000 IU of vitamin D3 per day, which comes from sock-eye salmon. We have not had much sun this winter –lots of rain or overcast days.

    What should I be doing to amass bone with a spinal fracture? What is missing in my diet. I am 70 years old and had consumed lots of calcium, vegetables and fruit, and received vitamin D from the sun much of my life, until 2006. Now, I tend to exercise indoors more. Is that the problem? Is that the reason I keep breaking bones? Yes! I have been diagnosed with osteoporosis. But why? I thought I was eating right. And, I suppose my exercise of mostly lap swimming was wrong. Should have been walking more.

    • Thea

      Becca: Good for you for doing your best to research and take care of yourself.

      I am not a doctor, but I highly recommend the book: “Building Bone Vitality: A Revolutionary Diet Plan to Prevent Bone Loss and Reverse Osteoporsis” by Amy Joy Lanou, PH.D. and Michael Castleman. It is always easier to prevent rather than reverse a problem, so I don’t know how much mileage this plan will get you despite the cover claims. But what I can say is that I have read the book several times and find it highly credible, a good read, and very helpful. It’s available on Amazon if you are interested.

      Good luck and I hope you get some help.

      • beccadoggie10

        Thank you, Thea, for this information. I’ll order and the book and check what it has to say.

  • Doctor Gregor, thank you so much for sharing . I am both amazed and grateful for your generosity and knowledge.

  • Tommy

    Hi Dr. Gregor

    I recently had a blood test to check my vitamin d levels, and it turns out that it is at 13 ng/ml. It’s been recommended to me by my doctor to take the 50,000 iu once a week for 12 weeks, and then 2000 per day after that to bring my levels up. What are your thoughts on the mega dose once per week? Would it be better just to start taking 2000 iu per day instead? Also would the plant based D3 bring my levels up (I’m vegan). Any info would be great. Thanks!

    • It would depend on your clinical situation. Assuming you have no symptoms due to deficiency and no other compelling reason to quickly raise your vitamin D level a more gradual approach is reasonable although you need to work with your physician(s). You might start with Dr. Greger’s series of excellent video’s on Vitamin D beginning with Dec 5, 2011… and going until December 15, 2011… 9 videos in all). We don’t know what optimal levels are or even what are normal for a particular patient. In one study Hawaiian lifeguards had levels in mid 20’s and I wouldn’t recommend supplements for them. When you look at the curve in video… it seems like between 20 and 30 is reasonable. Remember low Vit D actually reflects a “sunlight” deficiency. I recommend sunlight exposure as able. Avoid tanning beds see… There is now evidence that sunlight exposure helps our arterial system via the nitrous oxide system… see talk by dermatologist Richard Weller: Can sun be good for your heart. So there are benefits to sunlight exposure beyond Vitamin D. You also have to remember that Vitamin D is a fat soluble substance and there are cases of Vitamin D toxicity. A somewhat confusing area but keep tuned as we learn more. I think a reasonable goal is to raise your Vit D above 20 but whether that is done via sunlight, supplements or a combo would be for you and your doctor to decide.

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  • Carol

    I’m trying to find certified Vegan D3 and gluten-free drops. What brand was in your video, please?

    • Gabriel

      Look for Vitashine. If you’re in the USA, Rabbit Food Grocery has it for the best price and ships it for a few bucks.

  • Very interesting. I never thought the source mattered. I guess it does. !

    • HereHere

      I generally find it helpful to summarize a study when posting a link. Otherwise, people will pass on it thinking it is spam or marketing. In this case, the link is interesting, a study paid for by a mushroom industry group, clearly showing that supplementing with D3 raised serum levels of Vit D the most; D2 was nonetheless highly effective at raising serum levels of Vit D, and a mushroom concentrate made from white button mushrooms was slightly better than Vit D2 supplement tested. The trial was very small: 25 participants total. The researchers remarked that other research shows that the higher D levels from supplementation could last from 6 months to several years.

      • Thea

        HereHere: Thank you for your summary. As you suggested, I personally never click on a link that does not have a good intro. And so l missed learning about this study/information. Thanks for taking the time to share.

  • Ronald Chavin

    The big picture is that both vitamin D2 supplements and vitamin D3 supplements are equally well-absorbed and have the exact same effect on 25(OH)D at doses under 5,000 IU per day. The only clinical difference is at doses higher than 10,000 IU per day, where vitamin D3 is more effective at increasing 25(OH)D than vitamin D2. In my opinion, this makes vitamin D2 slightly better (safer) than vitamin D3 because the terrible sting from the life-threatening side effects of vitamin D overdose would be less severe with vitamin D2 swallowers. The benefits of keeping our blood 25(OH)D between 24ng/mL and 34ng/mL, which is exactly the same as between 60nmol/L and 85nmol/L, applies to all forms of vitamin D including sunshine. [Mushrooms produce vitamin D1, vitamin D2, and vitamin D4 when exposed to sunshine or artificial UV light]. Because sunshine causes permanent damage to our skin and eyes, it is the WORST way to increase our blood 25(OH)D to optimal levels.

  • Gina

    Can you please share this information with Dr. Joel Fuhrman? He uses non-vegan d3 in most of his vitamins (leaving just a basic formula for vegans). I tried to email him but someone replied saying to just use the basic formula one. Please tell him that it is unnecessary in normal doses.

  • I wish I knew where to get this vegan vitamin D3!!!

  • Beth

    I am Vit D deficient and would like to take a plant based D. However, I was told you can only take D2 and that all D3 are animal based.
    I would so much appreciate direction and a good quality Vit D supplement to take.

    Thanks so much.

  • Nick

    The Vegan D3 is actually made from Lichen (the white stuff the grows on rocks).. not technically a plant.

    • Felicia

      Thank you – the horticultural definition of lichen: A composite organism made up of a fungus, usually an ascomycete, that grows symbiotically with an alga ora cyanobacterium and characteristically forms a crustlike or branching growth on rocks or tree trunks.

  • steff

    Does anyone else feel uncomfortably amped up when supplementing with vitamin D–either form? Anecdotally some friends tell me they also feel “caffeinated” on vitamin D, but several doctors I’ve consulted say it’s unlikely. I get a weird “head feeling” and totally wired when taking any significant amount of D.

    • Thea

      steff: I don’t have any problems taking vitamin D, nor does anyone I know.

      However, I wanted to address this part of your post:”…but several doctors I’ve consulted say it’s unlikely.” I have a situation where a close family member consistently experiences some terrible site effects while using a family of eye drop medications. The doctors keep telling her that the shaky feeling could have nothing to do with the eye drops. But the side effects go away when she stops the eye drops. The problems come back when she starts the eye drops again.

      My point is: Despite how much all of us are the same, every person’s body is different. When it comes to medications, our reactions can be real and yet very different from the norm. Don’t let the doctors make you feel like you are crazy. If you experience problems on vitamin D, then you do. Start from that point, and then you can figure out what you want to do about it.

      I know this isn’t that helpful from an advice or data perspective, but I thought you might appreciate the moral support. Your story brought back what my family member is experiencing and it makes me angry that the doctors won’t listen to her.

      Best of luck to you.

    • Did you get this side-effect with different brands of vitamin D? Maybe it is the brand you are using, but that would not explain why some of your friends report the same occurrence.

      Do you take the pill w/ or w/o food? For example, if I drink coffee on an empty stomach it can throw me into a full on panic attack at times, but if I drink it w/ a meal it seems to be okay. Perhaps vitamin D is the same way?

      Another thought I had is do you need to supplement w/ VD? Maybe you are not VD insufficient or deficient and the reaction you get might be your body saying, “Hey, enough already. We’ve got what we need right here.”

      • Thea

        WholeFoodChomper: Wow. Now *that’s* a really helpful reply. Great questions and thoughts.

    • HereHere

      I haven’t observed any effects, cognitive or otherwise, from supplementation of D2. I only supplement Sept-April, due to a low sun angle in my region.

    • Susan

      If my vitamin D level is low as from the ridiculously low level recommended by the American Medical Association, I do not heal or make bone properly.

      Before I was diagnosed with osteoporosis in 2006, I had been supplementing with 1000 mg calcium, magnesium, and 400 IU vitamin D. The calcium was too high and the vitamin D way to low, as I learned when I had the level tested years later.

      Now, eating a plant based diet with careful selections of plant foods high in calcium, magnesium, boron, and supplementing with vitamin D3, I receive most of my calcium and magnesium from plants, and vitamin D3 from whatever source Andrew Weil, M.D. has.

      It does not bother me as to the source because I know the repercussions of a level too low. And, before I was diagnosed with osteoporosis, I swam in the sun for 2 hours every day. (Swimming alike dairy does not make strong bones and does not prevent osteoporosis. Only weight bearing exercise does, I learned afterwards.)

  • TMR

    I would not promote animal sources of Vitamin D because I’m an ethical vegan. There are a couple of plant-based vegan D3 supplements available. One is Vitashine D3. I’ve been taking it for some time now as I was D deficient despite getting enough sun (apparently D deficiency is widespread today) and it has worked very well in keeping up my levels. I have my D blood levels checked each year.

  • Evelyn

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  • AlwaysWorking

    To me it sounds like vitamin D2 might be BETTER than D3.


    As Dr. Greger said, if you already have enough vitamin D in your blood (from sunshine or whatever), vitamin D2 won’t increase your vitamin D blood levels (look at 3:23 of the video, they mostly stay at the 70-80 nmol/L range). And too much vitamin D is associated with a decreased lifespan.

    In the doctor’s other video about Vitamin D, Morality, and the U-shaped curve, we want to be a little above 70 nmol/L (i.e. 30 ng/mL) measurement to best ensure a long life. Check out the 1:30 mark of this other video.

    But with vitamin D3 supplementation, it might get you into the unhealthy levels if you are already at healthy levels.

    For those of us not wanting to get our vitamin D levels tested all the time, isn’t it just easier to consume vitamin D2 everyday and not worry about it?

    One possible problem would be the study at the end that didn’t associate D2 with a longer life, but that is probably due to the megadoses of D2 used instead of daily doses.

    I think the megadose explanation is correct. I found this information related to a single oral doses of 50,000 IU for a 28 day period. “Both ergocalciferol [vitamin D2] and cholecalciferol [vitamin D3] produced similar initial increases in serum levels of 25-hydroxyvitamin D [made in the liver] over the first 3 days, indicating equivalent absorption. However, levels continued to increase with cholecalciferol [D3] and peaked at day 14, whereas levels decreased rapidly with ergocalciferol and were no different from baseline at day 14.” link

    This means you probably won’t have optimal vitamin D levels everyday if you just do a megadose of D2 once a month. And, thus, probably won’t get the lower mortality benefit.

    One should also note there are two types of 25-hydroxyvitamin (a D2 and D3 version, 25(OH)D2 and 25(OH)D3, respectively), the chemical we test in the blood to calculate vitamin D levels, that is made in the liver, and from there the kidneys convert both types to the active form of vitamin D (which also has a D2 and D3 version, 1,25-dihydroxyvitamin D2 a.k.a 1,25(OH)2D2 and 1,25-dihydroxyvitamin D3 a.k.a 1,25(OH)2D3).

    Here is a great website showing a simple image of the different D vitamins but they refer to them with different, longer chemical names.

    Since the final, active form of vitamin D from D2 and D3 are two different chemicals, I have to agree with Dr. Greger that we need to wait for more studies before we can say D2 is just as good or better than D3 when it comes to morality (maybe after two years a study like that is out by now?).

    However, given the evidence above and since, as far as we know, the two active forms function the same, I think D2 is going to be proven the better vitamin (if taken daily).

    (Sorry for the long rant, I originally disagreed with the video above and tried to prove it wrong, but ended up pretty much agreeing in the end. However, I figured some of my fellow nutrition nerds would like the info I found.)

    • Vitamin D3 supplementation made my blood levels higher than I wanted so I’ve bought D2 again to take when my current bottle of D3 runs out. Vitamin D2 is cheaper, too.

  • Teresa

    Thank you for the information, Dr. Greger. However, I’m disappointed about the presentation of supplements made from sheep’s wool without any comment/hint about the disturbing exploitation involved of these gentle creatures.

  • Tia Haenni

    What about the use of UV-B sun lamps during the winter months? I’ve heard good and bad about D supplementation. Looking for the most natural solution to dangerously low D levels besides moving south. :)

  • Jeff Remas

    Here is another study that is now going to potentially cause some confusion or require additional studies unless they already exist. I hope there is a video covering both ends of the spectrum on this one in the near future.
    Thank you,


  • At 3:08 he says “and if you’re not vitamin D deficient…. D2 from mushrooms or supplements doesn’t appear to raise your levels (of serum 25 (OH)D) further”

    Does this mean that vitamin D2 is less likely to cause toxicity? Since once you reach a healthy level its harder for more doses of D2 to keep raising levels like D3 does?

    I would love Dr.Michael Greger to answer this.

  • At 3:08 he says “and if you’re not vitamin D deficient…. D2 from mushrooms or supplements doesn’t appear to raise your levels (of serum 25 (OH)D) further”

    Does this mean that vitamin D2 is less likely to cause toxicity? Since once you reach a healthy level its harder for more doses of D2 to keep raising levels like D3 does?

    I would love Dr.Michael Greger to answer this.

  • Wade Patton

    As it appears that this is the latest Vitamin D (isn’t it really a hormone?) video, I’ll comment/request here. Of course “vitamin D” never comes naturally from food sources but can be a health issue.

    Dr. Popper reviews a new study that shows 5-fold buildup in sub-cutaneous fat of study subjects where blood levels only increased 60%. Is there a level where this buildup in the fat will become toxic or affect other biological processes negatively?

    I’m getting plenty from the sun yet this year but wonder if I should continue with the D3 supplements I have on hand. I know what your current recommendations are, but I haven’t seen the latest issues addressed or anything less than two years old here.

    Her video:

  • 1hopefulman

    What about eating sardines once a week for our vitamin D?

  • Celeste Yarnall

    I am using an FDA registered class one medical device twice daily that makes everything I take more effective including of course my organic whole food supplements (vitamin d included with K2) as well as my own nutrition and my own oxygen, because using it daily enhances blood flow, cardiac function, etc., on a microcirculatory level by up to 30%. It’s from Europe and has 17 years of solid testing behind it and full FDA approval is pending and due in the next 3-4 months. I would love to share this with you privately, if you are open to chatting about it my email is

  • Sacred Sounds

    Vitamin D drops were prescribed to my baby since he is exclusively breastfed. Discovering that these drops were not vegan i went about looking for a version that i could give him and found D2 drops. Are those as good?

  • sustainability

    I was curious, there is a blog that says Garden of Life’s certified vegan D3 is actually derived from lanolin (
    and that Garden of Life told them that there is no known plant source
    of Vitamin D3. Garden of Life says on their site that the only 2
    sources of D3 are the sun and animal derived (
    they actually feed lanolin to the yeast to make it certified vegan D3.
    I know that alot of the organic food I buy in the store was grown with
    animal derived fertilizer. There are a few foods that are both organic
    and “veganic” (no animal fertilizer) like from the company One Degree.
    Regardless I would like a truly vegan source of D for the winter months.
    Is Garden of Life right? Your video ( says there are non-animal sources of D3? I would like to learn more.

    Also, Your book says to take D3 but does not mention D2 at all. Your video (
    seems to imply, if I understood correctly, that D3 might be preferable
    but there needs to be more data as this evidence was found only using
    mega dose studies. So does that mean that taking D2 in the winter months
    as long as my starting levels are ok could be equally beneficial?

    I am considering taking D2 instead of “vegan” D3 because of Garden iof Life’s claim, and wanted to run it by you first.

  • sustainability

    Garden of Life says on their site that the only 2 sources of D3 are the sun and animal derived (
    they actually feed lanolin to the yeast to make it certified vegan D3. Thoughts? I realize that alot of the organic food I buy in the store was grown with animal derived fertilizer. There are a few foods though that are both vegan and “veganic” ( grown with no animal fertilizer) like from the company One Degree which I definitely buy when it’s available. So I would like a truly vegan source of D for the winter months. I am going to try vitamin D2 so I know for sure it’s vegan. I understand that it can raise low levels yes? How large of a dose of vitamin d2 is still effective? I have heard up to 4,000 IU and 5,000 IU is still effective. Is D2 effective at doses any higher than 5,000?

  • FreeWilly

    How about vit. D synthesis/absorption and cholesterol? Since I am on a WFPB diet with extremely limited animal product intake (cheese once weekly, about 2 tbsp.), how can I make sure that I absorb the vit. D2 I get from mushrooms or the vit. D supplement I take?

  • KatiM

    I take Garden of Life Vitamin D3 5000IU, which is a whole food product.

    Vitamin Code RAW D3 is the only RAW, vegetarian, whole food vitamin D3 formulated with RAW Food-Created Nutrients™. Cultivated with live probiotics, antioxidants, enzymes and nutrient-specific peptides, RAW Food-Created Nutrients provide natural recognition of nutrients by your body. RAW Vitamin D3 is a whole food vitamin D complex that is gluten AND dairy-free, with no binders or fillers.

  • KatiM

    In approximately 6 months, my levels went from the extremely low 8ng/mL to 30ng/mL.

  • Alex

    Excellent video, Dr G. Thank you. I’m a ghostly redhead who avoids the sun (except when I don’t :D ) and lives much of the year between 50-70 degrees N. Do I understand correctly that supplementing daily with D2 would be perfectly reasonable? Also, were the UV experiments on growing mushrooms or picked store bought mushrooms? Is this something we could reliably, reasonably, experimentatly, try at home?

  • Michael
  • matchbox555

    At 3:08 he says “and if you’re not vitamin D deficient…. D2 from mushrooms or supplements doesn’t appear to raise your levels (of serum 25 (OH)D) further”

    Does this mean that vitamin D2 is less likely to cause toxicity? Since once you reach a healthy level its harder for more doses of D2 to keep raising levels like D3 does?

    I would love Dr. Michael Greger to answer this.