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The Flu Shot: Helpful or Harmful

The Flu Shot: Helpful or Harmful

The government says everybody should get the flu shot every year.  But does it work?  Is it safe?  And do we really need it?

One very reliable way to determine the effectiveness of the flu shot is to look at the database analysis presented by The Cochrane Collaboration, an independent group of scientists who have no link to any industry or government agencies.  After analyzing all of the data on the flu shot, they have concluded that it really doesn’t work well.  It doesn’t even cover most of the influenza infections that people get.

For certain populations, I do think a flu shot is necessary.  For people who are debilitated, people with respiratory or developmental problems, and for people who are prone to getting very sick and could die from the flu, I think it’s worth getting the shot.  It may not work that well, but it provide some benefit to those populations.

But for anyone else, I don’t think the flu shot is necessary.  I know this goes against government recommendations, and I know there’s a lot of controversy about it.  But I encourage you to do your own homework.  Read the blog that I wrote that extensively documents the science behind why the flu shots don’t work as well as we think they do, and why they might be harmful.

Here’s one dirty little secret about the flu shot: it contains mercury.  Most of the flu shots that are administered in the US are from multi-dose vials, which contain multiple flu shots in one little vial.  To preserve it, they add mercury or Thimerosal.  A cumulative dose of Thimerosal over your lifetime could have a negative impact on your health, because mercury is a known toxin.  It causes immune problems and neurologic problems like dementia, memory issues, and other issues. So, if you’re going to get the flu shot, make sure it comes from a single-dose vial, which doesn’t have Thimerosal in it.


  1. The flu shot doesn’t work well, and there are many other things you can do to stay healthy.
  2. It may contain mercury, so if you do get the shot, be sure avoid the kind that comes in a multi-dose vial with Thimerosal added.

So, how do you prevent the flu without getting the flu shot? 

I’ve written a blog on this subject that explains exactly how to build up your immune system, what supplements to take, and what foods to eat to make sure you don’t get the flu.  There are simple but highly effective things you can do, like taking vitamin D.  When you have adequate vitamin D levels, you can dramatically reduce your risk of flu.  And there are many other suggestions that I provide in the blog.  So, check it out and learn what you can do to prevent the flu.

I encourage you to share this House Call with your friends and family on Twitter and Facebook.  Sign up for the newsletter, and submit your questions, so that, next week, I may make a House Call to you.

Learn more:

Should I Get the Flu Shot?

Supporting Your Immune System When You May Need It Most

Supplements to Support Your Health in the New Year

Wintertime Immune Support

Mark Hyman MD is the Medical Director at Cleveland Clinic’s Center for Functional Medicine, the Founder of The UltraWellness Center, and a ten-time #1 New York Times Bestselling author.

Comments (9)

  • I was in the “high risk” category you mentioned, because I have asthma, so I got talked into a flu jab about a decade ago. I then fell seriously ill, could barely walk, was practically bed bound for months, and kept getting the flu and other viruses every winter making my health, that had gradually improved slightly in the warmer months, once again plunge into serious illness. I was in a huge amount of pain, exhausted from the moment I woke, and worse through each day, my brain barely functioning. I’ve since been diagnosed with Fibromyalgia.

    I have, in recent years, been reading up on a lot to do with my health, and have started taking supplements, vitamin D, (because even after high dose for two months my level was 6.8), magnesium – which has taken away my asthmatic wheezing (it comes back when I forget to take it), multi mineral (includes iodine and boron amongst other things), and vitamin C, which, along with the zinc in the multi min, is helping me to stave off colds.

    I disagree that the people at high risk should have the flu jab. I think those people are just at the further end of the scale that the “normal” people you mention are on, those who can do “other things” to avoid the flu. I believe us “high risk” folk are just in way more need of the things that help. We are more deficient in essential vitamins and minerals, and at a far higher risk of being damaged by vaccines, whether they contain Thimerosal or not (as they contain other dangerous things.)

    If I could go back and not have that flu jab, I would. It’s given me ten years of living hell, excruciating pain at times, it’s restricted my life, taken away all of my 30s, leaving me stuck indoors barely functioning for a large portion of that time. And I’m far from being the only one this has happened to – there are MILLIONS like me with “ME” and “Fibro”.

    I believe people like me have been malnourished by our standard diets and poisoned with injected toxins or environmental toxins such as mould, and even mercury (“silver”) fillings. What we need isn’t more toxins, what we need is more nutrition. More than the average person needs.

  • I have a synthetic Mitral valve and was told by my doctors (cardiologist) I need to have flu shot yearly before winter flus start. So I have done so for over 2 decades.
    I am very conscious of what I feed my famiky and yes I cook daily. My in laws grow a lot of their own vegetables

  • My husband takes medicine which compromise his ammune system. He recently has developed fibromyalgia. He gets a flu shot every year and every year, he gets horribly sick with the flu. I don’t get the flu shot and I do not get the flu. He eats dairy like crazy. I try not to eat corn, wheat, dairy or sugar. I supplement with Vit C all year. Can it really be that easy to prevent the flu?


  • I wonder if the “risk” category recommended for vaccination here is something dr Hyman *must* mention as a legality. Because it seems that people with low immune system might get momentary benefit, but it also might be a contributing factor to the low immune system to begin with (I know that was the case for me). And as for neurotoxins and developmental disorders, I think the regressive risk is starting to get clear.

    However, I thank you for walking the line and saying something.

  • My college freshman daughter refuses to get the flu shot. She is going to a very difficult, very expensive college and lives almost 4 hours from home. She cannot afford to miss a week of school due to illness. She has low blood pressure, requires a lot of sleep and is not very energetic overall. She takes vitamin D. What can she do to stay healthy and avoid the flu aside from hand washing?

  • I realize that this is anecdotal but five years ago my 83 year old mother had a flu vaccine administered at a local drug store. My mother’s doctor insisted that mother get the flu vaccine because of her age. Two weeks later she came down with the worst flu that she ever had. My mother was not prone to having colds or the flu, and even in her advanced years she was quite energetic and very independent. Anyway, this flu virus my mother suffered caused my mother to be bedridden for nearly two weeks. I took care of her and thankfully she still had an appetite and was taking in fluids. When my mother’s flu had subsided she was very weak. A month later my mother had a serious fall in her living room. Less than a year later she died. My mother was a healthy, active and jovial lady before she contracted the flu, became very weak, then fell and later died. My mother’s doctor “assured” me that my mother’s flu vaccine had nothing with her getting so ill. He said she was likely contagious when she got the flu shot. I don’t know what to think.

  • My experiences with the flu vaccine have been helpful not harmful. The vaccine helps prevent getting the flu for me anyway. My brother on the other hand, has not had the best experience with the vaccination. When he received the shot from my mother he said he was going to pass out. My mom and I didn’t think he was serious, but he was. However, he did not faint because of the vaccine itself, but because he is not a fan of getting shots.