NUTRITION

Flashback Friday: Do Vitamin C Supplements Prevent Colds but Cause Kidney Stones?

What are the benefits and risks of taking vitamin C supplements?

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What about intravenous vitamin C? I’ve got a whole video series on that, including:
• Intravenous Vitamin C for Terminal Cancer Patients (
• Vitamin C Supplements for Terminal Cancer Patients (
• The Role of Vitamin C in the Treatment of Terminal Cancer (

If you’re not taking vitamin C supplements for pharmacological effects and just want to know how many vitamin C-rich fruits and vegetables to eat every day, check out my video What Is the Optimal Vitamin C Intake? (

Is there anything we can put into our mouth that really might help prevent colds? These videos will point you in the right direction:
• Can Gargling Prevent the Common Cold? (
• Preventing the Common Cold with Probiotics? (
• Nutritional Yeast to Prevent the Common Cold (
• Kiwifruit for the Common Cold (

And, if you’re interested in learning about the most important steps you can take to prevent kidney stones, look no further than my videos How to Prevent Kidney Stones with Diet ( and How to Treat Kidney Stones with Diet (

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Thanks for watching. I hope you’ll join in the evidence-based nutrition revolution!
-Michael Greger, MD FACLM

Captions for this video are available in several languages. To find yours, click on the settings wheel on the lower-right of the video and then “Subtitles/CC.” Do you have feedback about the translations in this video? Please share it here along with the title of the video and language:

Image credit: Kristina DeMuth.

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