The People's Perspective on Medicine

Vitamin D Strikes Out Against Heart Attacks and Cancer

In the VITAL trial, vitamin D strikes out for preventing heart disease and cancer. Are such supplements completely useless?

Millions of Americans are low in vitamin D. They are at higher risk for a range of health problems, from asthma to osteoporosis, hypertension, rheumatoid arthritis and cancer. These individuals may be advised to take vitamin D supplements but a new study called VITAL published in the New England Journal of Medicine suggests that vitamin D strikes out.

How Do We Know Vitamin D Strikes Out?

The VITAL study demonstrates conclusively that vitamin D pills do not reduce the risks of cancer or heart disease (NEJM, Nov. 10, 2018). Nearly 26,000 people were randomized to take 2000 international units of vitamin D3 or placebo every day for more than five years.

The Envelope, Please:

Overall, there was no significant difference between the two groups when it came to survival. There were no fewer heart attacks, strokes or other cardiovascular complications in the vitamin D group. They were also equally likely to die from invasive cancer.

Based on this study and other trials, including an investigation that considered cancer prevention, it seems that vitamin D supplements may not be an adequate substitute for sun exposure.

Rate this article
3.7- 34 ratings
About the Author
Terry Graedon, PhD, is a medical anthropologist and co-host of The People’s Pharmacy radio show, co-author of The People’s Pharmacy syndicated newspaper columns and numerous books, and co-founder of The People’s Pharmacy website. Terry taught in the Duke University School of Nursing and was an adjunct assistant professor in the Department of Anthropology. She is a Fellow of the Society of Applied Anthropology. Terry is one of the country's leading authorities on the science behind folk remedies. .
Vitamin D Deficiency

Download 8 pages on symptoms of low vitamin D and ways to overcome deficiency, for children and adults. Information on avoiding vitamin D overdose and which supplements are best, all in 8 pages.

Vitamin D Deficiency
Join over 150,000 Subscribers at The People's Pharmacy

We're empowering you to make wise decisions about your own health, by providing you with essential health information about both medical and alternative treatment options.

Showing 49 comments
Add your comment

To trumpet something like “Vitamin D doesn’t help with cancer or heart attacks!” is very misleading. I get many health and nutrition newsletters, both online and in print, from top colleges and medical schools. I’ve read literally THOUSANDS of studies and articles touting the great and numerous benefits of vitamin D. If it turns out that EVERY SINGLE ONE of those was wrong, then I may as well move to the forest and live under a rock. I am SURE that vitamin D contributes to overall health and wellness, even if it can’t be proven that it diminishes heart attacks, etc. All that’ll do is convince people that vitamin D is worthless, cuz all they’ll remember is “doesn’t help.”

Sounds like a poorly-designed study to me. Should have measured a person’s D blood levels to determine if higher levels correlate with reduced cancer or heart attacks.

I stopped my Vit D3 several years ago & my levels dropped. My doc had me to start back again. I have increased myself to 6000 IUs daily. My HDL is great, cholesterol is good. My doc always does a vit D screen on me when I have my annual blood work. I’m female and 70 and have Polycythemia Vera so my blood is checked often.

The previously mention combination of adding K2 when taking vitamin D3 is correct but you should also add in magnesium. Hippocrates said ‘let food be your medicine’- Big Pharma is only interested in profit. Hope adding this link is allowed as it explains the mechanism very well:

I have 2 whole bottles of vit d to use up. Maybe by then another study will say they help with something.

Uplifting, well thought-out comments for sure. Especially about calcium. I remember some years ago when 1200mg. of calcium was recommended Even 1500 mg. Well now I have calcification in my aortic artery [found on ultrasound for ribs after an accident], and who knows where else.
I too do not get the flu without having the flu shot. Too many good things about taking D3. Unfortunately did not learn about K2 [MK7] until a few years ago.

Thank you to all who share their experiences.

Constantly amazed by the number of people I talk with that do not know to take Vitamin D with fat, as it is a fat-soluble vitamin. No mention if the participants in the study were instructed to take the vitamin D with a fat source.

I agree about the study being set up to fail. 2000 mg is too low. I also wonder about the quality of the D they used. I am part of the Grassroots Health Vitamin D Study. You MUST test your levels with a reliable test. Sometimes you need more D based upon the season, your weight, and a variety of other issues. Grassroots Health has great statistics to back up their recommendations, and they have recently added Omega 3 testing and other tests to their initiative.

As a scientific research student, I would think that the researchers would have tried to construct a control group with a placebo, an experimental group with 2,000 unit, 4,000 units, and 6,000 units of vit D to discern the therapeutic and or toxic dosages. With the opportunity to create such a large study, I am disheartened the construction was very limited in dosage testing.

Your site has so many different and changing opinions in both your articles and the replies on all topics you cover that it is usually impossible for the reader to come to any helpful conclusion with peace of mind on any of the covered material. It just makes folks more confused! You’re almost better off not knowing much about any of your topics, using basic common sense, and of course having a good doctor and possibly a current Merck Manual at home. Just pretend for a moment you’re a layman and re-read this D3 report and replies. Are D3 supplements good or bad?. I REST MY CASE.

Mike, Vitamin D3 supplements don’t seem to prevent cancer or heart attacks, but they probably have other benefits not addressed by this study.

My doctor suggested a year ago that I take 3000 IU of vitamin D daily. In the past 12 months I have not had a single cold or virus. Could be a coincidence, or perhaps the D is responsible. I was getting one or two colds every year. I’ll keep taking it.

What did they really expect at 2000 IU’s/day? Not enough intake to optimize levels.

Always feels like these types of studies are specifically set up to fail.

I’m surprised that this conclusion is being drawn without anyone questioning whether perhaps the dose (2000 iu’s) is inadequate. A much more effective study would have measured blood levels of Vitamin D, and dosed variably in order to achieve certain levels. Many people can take even amounts as high as 5000 iu’s a day and still not have optimal blood levels of Vitamin D.

A further question is ‘what is an optimal blood level of Vitamin D?’ We’re told that ‘normal’ blood levels are between 35 and 65. However, some physicians want their patients’ blood levels closer to 50, and consider 35 too low. There is one rheumatologist I know of who wants his patients’ blood levels at 90! Several of these patients report being able to get out of bed, out of pain, and back to work. How can a study that just gives 2000 iu’s a day to everyone come to the conclusion that ‘Vitamin D doesn’t work for…’ ?

Perhaps he amount of Vitamin D in the study was insufficient to do good. My doctor prescribed 5,000 units and almost immediately I noticed a reduction in the generalized anxiety I had been experiencing. I wasn’t expecting this or anticipating any noticeable benefits at all. I took it because he suggested it. Let’s have another study or two with a higher dosage.

I so agree!

I don’t take Vit D as a preventive measure for Heart attacks nor Cancer. I take vitamin for my immune system, to keep healthy. I chose not to stand in the sun, taking a chance of getting Skin Cancer. I’ll take my chances with Vitamin D thank you very much. This was a poor study..

For years I was always proned to getting every bug that came down the pike. Of course, having a husband who was a teacher & 4 kids in school, I was exposed to lots of bugs. Three years ago the allergist as well as the rheumatologist thought I should get my D levels checked out & they were in the basement. I started taking vitamin D 2x daily & dramatically increased my levels to where the docs wanted them & I no longer got sick from everything that was around: so, I think that I am living proof that vitamin D levels are concern & when they are where they are supposed to be, we stay well & our own immune systems kick in & help us fight these germs.

I’ve read that the higher the Vitamin d, the higher the HDL cholesterol & that HDL helps lower glucose. I don’t think 2000 IU is enough “if” you don’t go in the sun which I sure don’t. I’ve been taking 5000 IU for several years. My HDL is around 75 and glucose normal. Whatever, I’ll keep taking it. I had the Vitamin D test done two or three times so I know what I take works. At first I was taking 10,000 a day and had it tested at 100 so I cut back. That 10,000 was overkill. I bet I’m around 50 if tested now.

I take up to 10.000 IU D VITAMIN a day because it helps me have less fibromyalgia and arthritic pain.

Isn’t vitamin D3 also supposed to be helpful for depression and as a preventative for osteoporosis?

For me, the key question is the level of Vitamin D3 in the blood, which has earlier, been shown to help strengthen the immune system and those who take supplements plus get adequate sun exposure have lower incidences of prostate cancer. I believe these studies helped to confirm the reasons for higher incidence of prostate cancer in dark-skinned (African-American) men when compared to fair-skinned/white men. My understanding is that dark skin reduces Vitamin D3 uptake; where-as fair skinned men get higher levels with less sun exposure. Supplementing with Vitamin D3 seemed to reduce the disparity between the races over time. I recall some of these studies were published in British journals.

2000 IU’s assured no positive results

Well, there is a simple explanation as to why the supplement didn’t work in the study, they weren’t taking enough and or they weren’t optimized. That study is totally flawed!

I am naturally severely deficient in Vitamin D and so about 8 years ago my doctor recommended that I take 10,000 iu’s of D3 every day. Since then my bone density has INCREASED. I cannot be in the sun because I had a melanoma removed several years ago. I don’t know if D has had any effect on my odds for having a heart attack or stroke, but it certainly is benefitting my bones. I do wonder if the fact that the study only gave the participants 2000 iu’s of D might have something to do with it seeming to have no effect on heart attacks and cancer. Perhaps taking more that 2000 iu’s would make a difference.

why not mention the Vit.D calcium absorption factor?

Fake study. Totally unsufficient doses!

My Dr told me to take 10,000 units of Vitamin D3 daily after doing bloodwork on me
I am fair skinned and do not do not enjoy the sun, so my levels of vitamin D were way too low
Avoiding the sun has helped me a lot by not aging my face, so I would rather take Vitamin D3 supplements than sitting in the sun
I notice I feel better when I take my D3
Since I am not taking it for for other reasons other than I don’t get enough sun I don’t think the study affects me
I also agree with another persons comments that big pharma seems to be being studies saying that things are not beneficial when I have seen myself that they are
Big pharma wants us to get in as bad health as possible because it means billions of profits for big pharma
If we take supplements they don’t manufacture that benefit our health big pharma makes less profits

Problem I have with this study is no Vit. D blood levels were taken to determine the proper dose and to monitor compliance of people actually taking the Vit. D. They have everyone the same dose of 2000 units.
Where is the science of pharmacy like everyone takes the same dose of all drugs. Sorry but this study is flawed big time.
So I rate this study as questionable. Seems they really did not want to prove Vit. D was effective otherwise Big Pharma cannot sell their medications which claim to increase bone density.

Having read the study, I am struck by two things. When the first two years of the study are excluded, there in fact appears to be a significant preventative effect on cancer. Here is the quote: “In both an analysis that excluded 1 year of follow-up and an analysis that excluded 2 years of follow-up, neither of which was specified in the protocol, the rate of death from cancer was significantly lower with vitamin D than with placebo.” I take it that by including the 1st and 2nd year of follow up the lack of results pulled down the overall benefit to be insignificant. Someone please correct me if I am misunderstanding something but it would appear that overall test results were manipulated.

Then there is the issue of why 2000 mgs. was selected. More than a few holistic doctors recommend 5000 mg. and even considerably more. And while the study carefully adjusted for age and race, I do not see any measurement of the obesity of the study subjects. Obesity hinders the absorption of D. I do not see that any test was made for absorption. This would be important given the 67 avg. age of participants as seniors frequently have absorption challenges with any nutrient.

In conclusion, I find the study inadequate to resolve the stated concerns of the study.

How unfortunate the researchers did not include a sample test group that took both Vitamin D3 and K2. Why are we so quick to say a supplement doesn’t work, when it’s just as plausible that the results were unsatisfactory because of the study design.

I’m sorry I can’t find the original research source article explaining the need to consume K2, along with D3, but I believe the advice women were given to increase their calcium consumption without the D3 and K2 most likely resulted in increased calcification of the arteries and calcium deposits around joints. Then doctors slowly started advising folks to take D3 to increase the absorption of the calcium. But without the K2 component, I believe that advice just made the problem worse. If K2 is the “traffic cop” that directs your body to put calcium where it is needed (strong bones and teeth), the lack of K2 in our diets may be the reason for the increase in heart disease linked to higher calcium. I live in Spokane, WA so I can only get D3 from sun exposure from June through August. The rest of the year, I plan to supplement to stay healthy.

Your introduction to this piece is grossly overstated. The study suggests that 2000 i.u. of vitamin D was not effective for the intended purpose. It says nothing about first determining what a person’s vitamin D status is, and then dosing according to actual need.

I have given up on “studies” simply because they contradict one another frequently or leave large
gaps in information and equally large questions. I read widely in medical and herbal and other
literature, current and not so current. So, I still take Vitamin D in moderate doses along with
my one-a-day, a probiotic, gelatin for my thin nails, hibiscus tea mixed with my regular tea which, along with blood pressure meds, helps keep my uncertain blood pressure at good levels ( 135/80} and am working to adjust my diet toward more fruits and vegetables.
I am 76 and have a neuromuscular condition that doesn’t keep me down. I also lead two very
active community ( activist ) organizations.

I took 1000 units daily for a month of Vitamin D and ended up with terrible bone and muscle pain in arms and hands. So bad in the end I was not able to sleep. What are the side effects of Vitamin D

To Barbara Grossart; I read last week that D3 taken too late in the day will interfere with Melatonin (which ushers you into slumber). So, that night I didn’t take my D3 with PM supplements and went right to sleep instead of gazing at the ceiling for an hour or more, while waiting and waiting to fall asleep. Now I take ALL my D3 with my AM supplements and conk right out at night. Yay!! Also, L-tryptophan (also found in turkey(!)) or chamomile tea is supposed to help you fall asleep. What the heck– try them ALL!! And, I use Malic Acid for my fibromyalgia and arthritis pain. Baylor Univ. did a study on Malic, and (hooray!!) it WORKS!! I use the Magnesium Malate Form.

I hesitate to believe any more studies….I will continue my Vit D and Omega fish oil supplements.

I’m with you on this..

Quite frankly I wasn’t aware that avoiding cancer was the primary, or even a lesser reason for taking Vitamin D. It would seem to me that it should have been mentioned in the article that the other reasons for taking Vitamin D were unaffected by the results regarding cancer and that one shouldn’t stop taking Vitamin D as a result of the cancer findings.


Same year there will be a study reporting the opposite!

I think ‘Big Pharma’ underwrites a lot of these ‘negative’ studies and we all know why. I figure this way: If it’s not going to hurt me and may possibly help me, it’s my money I may or may not be wasting. But as long as we have the greedy, money-hungry ‘Big Pharma’ in the mix, I’ll stick to natural substances insofar as I can.

I couldn’t agree more! Every time “Big Pharma” says a supplement or vitamin doesn’t help, I KNOW I should be taking it. Meanwhile , They keep recalling drugs all the time , Just saw HBP meds recalled for having jet fuel component in it!

If I can’t be out in the sun too much then how can I get a recommended amount of vitamin D?

I couldn’t agree more. Since I started taking Vitamin D , I do not catch colds or flu. I’ll be my own “study” on Vitamin D.

Heart attack and stroke prevention are not the reasons I recommend Vitamin D. Do a study on immune system modulation in auto immune people, that is a better question to ask about Vitamin D.

I take vitamin D to protect me from the flu, not for the reasons in the article. So far, it seems to be working. I haven’t had the flu in 20 years, even though I teach in a university and am surrounded by people who apparently are carrying the flu (since they miss class with that excuse), and I don’t take flu shots.

Good point . My Dr. Has me taking 5000 a day. My question now is about k2 and its role in absorption.

I’m with Judy!! I used to have the flu every winter. It’s now been more than a decade since I’ve been down and out with the flu. I don’t do flu shots.

Judy, That is amazing. How much vitamin D do you take per day to protect yourself from the flu?

* Be nice, and don't over share. View comment policy^