About the Post

Author Information

I am a New Zealand registered nurse and nutritionist (Grad Cert Sci: nutrition, Massey Univ). I am a Certified Zone Instructor, and have worked teaching Zone diet principles to hundreds of clients over the last 10 years. More recently after finding that eating Paleo food choices was the "icing on the cake" health wise, I have become a Paleo enthusiast and teacher. Follow me on twitter @juliannejtaylor

Is garlic a good remedy for colds and flu?

Harvesting Garlic, from the 15th century manuscript of Tacuinum Sanitatis Bibliotheque Nationale, Paris

A recently published study confirms one of our oldest home remedies – garlic improves your immune response to colds and flus.

A long time ago, in my 20’s I lived in London and spent time travelling around Europe. I spent a day with a German woman in Spain, who at the time had a bad cold and ate several cloves of raw garlic between slices of bread. She told me it was a common remedy in Germany for colds. And my Scottish flatmate in London (room-mates for you in USA), used to boil up at least a dozen garlic bulbs and make a thick garlicky soup to treat her colds.

Supplementation with aged garlic extract improves both NK and γδ-T cell function and reduces the severity of cold and flu symptoms: A randomized, double-blind, placebo-controlled nutrition intervention

Aged garlic reduces cold and flu severity: RCT data

Supplements of an aged garlic extract may reduce the number of days a person suffers from cold and ‘flu by 61%, says data from a randomized, double-blind, placebo-controlled study.


Background & aims

Earlier studies show that dietary bioactive compounds can modify proliferation of γδ-T cells. Garlic contains numerous compounds that have this potential and, in addition, has been shown to influence NK cell function. Our primary aim was to demonstrate that aged garlic extract could modify these immune cells.


A randomized, double-blind, placebo-controlled parallel intervention study recruited 120 healthy subjects (60 per group) to determine the effect of aged garlic extract supplementation (2.56 g/d) on immune cell proliferation and cold and flu symptoms.


After 45 d of consuming an encapsulated aged garlic extract, γδ-T cells (p = 0.039, n = 56) and NK cells (p = 0.043, n = 56) were shown to proliferate better compared to placebo. After 90 d of supplementation, illness diary entries showed that the incidence of colds and flu, a secondary outcome, were not statistically different; however, the group consuming the aged garlic extract appeared to have reduced severity as noted by a reduction in the number of symptoms reported (21% fewer, p < 0.001, z-test of proportions), a reduction in the number of days (61% fewer, p < 0.001, z-test) and incidences (58% fewer p < 0.001, z-test) where the subjects functioned sub-optimally and the number of work/school days missed due to illness (58% fewer, p = 0.035, z-test).


These results suggest that supplementation of the diet with aged garlic extract may enhance immune cell function and that this may be responsible, in part, for reduced severity of colds and flu.

Tags: , , , , , ,

6 Responses to “Is garlic a good remedy for colds and flu?”

  1. I will bet it also helps kill the spread of cold. Garlic breath ugh.

    February 2, 2012 at 1:28 am Reply
    • Bad breath jokes abound!
      Well you can always take aged garlic extract, I haven’t noticed bad breath from that.

      February 2, 2012 at 2:50 am Reply
  2. James R #

    Yeah yeah…. But then you have epic bad breath! 🙂

    February 2, 2012 at 2:08 am Reply
  3. thats probably why it works in the first place – noone is coming near you, hence no germs and no flu 🙂

    but seriously – nice find

    February 2, 2012 at 8:09 am Reply
  4. outbreak flu #

    Dear Julianne,
    This might be off topic, however, There is a your home solution for the everyday cold that is made up of eating a clove of garlic a day. I in reality don’t have an appetite, so producing a meal out of it will not likely operate. But I want to try out this out.
    What can I dip this garlic clove in to make it extra nice?
    I look forward to your next post

    February 23, 2012 at 7:15 pm Reply

Leave a Reply