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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.