When it comes to immunity, it’s hard to find a supplement with a better resume than olive leaf extract. 

Olive leaves – and the extract made from them – have been shown to have anti-inflammatory, anti-oxidant, and even anti-viral activity.(1,2,3,4) 

Yup, olive leaves – the leaves of the same tree that produce one of the world’s healthiest oils – are actually loaded with the same compounds found in olive oil, the ones that are responsible for so much of olive oil’s benefits. 

They’re called polyphenols. And they offer a big upgrade to your immunity. 

What are polyphenols and why should I care? 

Polyphenols are a group of protective, natural chemicals found throughout the plant kingdom primarily in berries, walnuts, olives, tea, grapes, and other fruits and vegetables. Remember, even a healthy person’s body produces damaged cells that – if not eliminated right away by your immune system – can become a major health threat. 

Polyphenols “deactivate” these time-bomb substances. They support your immune system because they fight off the damaging action of molecules known as oxygen free radicals.  That damage is called oxidative damage – and polyphenols, like the ones in olive leaf, help fight them. That’s why they’re called anti-oxidants.  

Without sufficient antioxidants on hand, free radicals create cellular damage that harms the immune system and slows down its functioning. 

And that’s not all the polyphenols in olive leaf extract do. In an article in the November 2009 issue of Nutrition Reviews, scientists reported that the bioactive compounds in olive leaf have antioxidant, blood pressure-stabilizing, plaque-inhibiting, inflammation-mediating, blood sugar-leveling and cholesterol-balancing effects. (5) 

What about Olive Leaf and Bacteria and Viruses? 

Bacteria are tiny one-celled organisms that have the power to divide and multiply by themselves. While many are not-so-friendly, for the most part they’re pretty harmless, and some of them – like lactobacillus acidophilus, found in yogurt and in our microbiome – are a boon to human health. 

Viruses, on the other hand, are a whole different “animal”. They can’t multiply on their own. Instead, they invade a “host” cell and take over the cellular machinery that allows them to reproduce and make more virus particles. The cells of the mucous membranes are particularly susceptible to virus attacks since they’re not covered by protective skin, and it is those cells – in the upper respiratory system – that are most affected by coronavirus. 

In fact, early research by the drug company Upjohn found extracts from olive leaves to be effective in treating infections from a large number of viruses, bacteria, and parasitic protozoans. (6) 

The Unique Properties of Olive Leaf 

According to Dr. James Privitera, these are some of the unique properties possessed by the olive leaf compound: (7) 

  • Interferes with amino acid production essential for viruses 
  • Controls viral infection and/or spread by inactivating viruses or by preventing virus shedding, budding, or assembly at the cell membrane. 
  • Directly penetrates infected cells and stops viral replication 
  • Stimulates a process called phagocytosis, an immune system response in which cells act like little “PacMen” and ingest harmful microorganisms and foreign matter. 

If you want to upgrade your immunity – and who doesn’t, these days? – olive leaf extract is just the ticket, especially when combined with the other nutrients recommended in the Challenge. 


  1. Cherif, Rahal et al “A Clinical trial of a Titrated Olea Extract in the Treatment of Essential Arterial Hypertension” J Pharm Belg 51 (1996) 69-71 (print) 
  1. Privitera, Jr Olive Leaf Extract: A New/Old Healing Bonanza for Mankind. Covina: NutriScreen, 1996 (print)