In a World Without Medicine, These Plants Could Save Your Life
Protection when the government has failed.
Things were already getting pretty bad.
Now the Trump administration, via RFK Jr. and his anti-vax crusaders, has halted work on next generation Covid vaccines. They’ve also canceled a crucial meeting to determine this fall’s flu shots. They’ve even started to consider canceling the $500 million allocation for Moderna’s H5N1 bird flu vaccine.
Five years ago, we looked to plants to protect us from pathogens because vaccines and treatments weren't coming anytime soon.
Well, here we are again.
I’ve combined all my work on this topic into one super post that overviews the available research, dose recommendations, and brands—because it’s not just whether they work, it’s who sells them. I’ve done a ton of digging and found many, many plant-based compounds that can help your body fight off infections. Some of these, like star anise, rival Tamiflu when they’re used effectively. Not everyone can use them, and you should always consult a doctor if you’re taking a medication or have a health condition that could impact their use. Some of these supplements aren’t meant to be taken every day all year long. You take them when you think you’ve been exposed to something. You take them for a few weeks. Then you should give your body a rest, because too many supplements are hard on your liver.
So, do they even work?
Yeah, they do.
A 2024 review of studies in Viruses identified 10 different plant compounds with broad antiviral properties and effectiveness specific to Covid—and in many cases several other viruses. As they write, "plant-derived molecules can tackle viruses by acting on different aspects of their infection process" and "inhibit coronavirus/host protein pathways" by blocking them. The authors initially identified 45 different compounds and then narrowed them to the 10 most effective.
Plants work because they contain terpenoids, flavonoids, phenols, and alkaloids that all demonstrate "high anti-viral potential against SARS-CoV-2 particles" as well as other viruses. They do this in a variety of ways that work across variants because they block virus entry while also tamping down replication and essentially "stopping its life cycle." Sounds good to me...
Let's get into it.
Ginkgo
First, ginkgo biloba contains two bioflavonoids called quercetin and rutin that can block Covid's 3CLPro BS PL-pro enzymes, as demonstrated in two different studies that looked at how they bind to parts of the spike protein. According to an article in Nature, 3CLPro plays a central role in virus replication. Ginkgo also contains kaempferol that inhibits Covid's envelope protein E, "consequently suppressing virus activity and proliferation." G. Biloba also brings an anti-inflammatory effect that can help with recovery as well. Ginkgo demonstrates broad antiviral and antibacterial properties, so it’s good to have on hand.
How much should you take?
The clearest study I found used 40 mg of extract three times a day, or 120 mg total for a standard supplement with 24 percent flavonoids and 6 percent terpenes. Basically, you’re getting 36 mg of pathogen-fighting compounds.
Where should you buy it?
According to the supplement watchdog Consumer Lab, you should go with brands like GNC, The Vitamin Shoppe, Nature Made, Nutrilite, or Life Extension. Consumer Lab analyzes these products to make sure they contain what’s advertised. They all made Consumer Lab’s cut.
Reminder: Ginkgo works on viruses largely thanks to quercetin and rutin, which are found in other supplements. If you’re taking Ginkgo to fight an infection, check the polyphenol and flavonoid content on other supplements to make sure you’re not getting too much of a given compound. Be careful when mixing Ginkgo, elderberry, echinacea, and St. John’s Wort. They contain quercetin and other flavonoids. According to Mount Sinai’s page on supplements, if you exceed 1 gram per day, it can cause kidney and liver damage.
Quercetin
Since many of the supplements with antiviral properties contain quercetin as an active compound, it’s worth looking into standalone quercetin supplements—especially if you just want something simple. With the best quercetin supplements, what you see is what you get. There’s no fluff.
The best brands offer roughly 500-600 mg per dose, and you don’t want much more than 1 gram anyway. The brands include Life Extension, Solaray, BulkSupplements.com, and Swanson. Thorne also sells a quercetin supplement, but that one wasn’t evaluated by Consumer Lab.
Star Anise
A 2008 study in the Journal of Medical Virology discusses star anise explicitly as a potential tool for an avian flu pandemic. Here’s the thing: It doesn’t seem to work very well (or at all) when it’s used on its own. But when you combine it with Quercetin, it can work “even at low doses.” A 2020 article in Phytotherapy Research confirms shikimic acid (from star anise) as the primary precursor molecule in Tamiflu—and “several other molecules with numerous biological benefits including the antiviral effects have been reported from the same plant.”
A 2011 lab study found that star anise reduced infections of herpes simplex virus by more than 99 percent. As this article explains, star anise is a fruit that grows in Vietnam and China. It’s used as a spice in many parts of the world. During the height of anxiety about bird flu in the 2010s, the companies that made Tamiflu (Gilead and Roche) were outright hoarding star anise, consuming nearly 90 percent of the world’s supply, and making a billion a year.
So, are you wrong to buy some and try it?
Hardly…
How much should you take, and where should you buy it?
Consumer Lab hasn’t evaluated star anise supplements, but a 2023 article in Biotechnology Advances indicates that you need .13 grams of shikimic acid to make one 75 mg dose of Tamiflu, from 2.6 grams of star anise. Various online sources say it’s okay to consume 3 grams of ground star anise a day. You would need about 5.2 grams to get enough shikimic acid to emulate two doses of Tamiflu per day, which is what doctors tend to prescribe for flu infections.
Combine that with a quercetin supplement.
Buy Chinese star anise. Don’t buy Japanese (it’s poisonous). You shouldn’t even be able to get Japanese star anise, but ya never know…
So, there you go.
Curcumin & Turmeric
Second, turmeric and curcumin "can either bind directly to the receptor binding domain of the viral S-proteins or secure ACE2 receptors of the hosted cell." Basically, they stop viral entry into your cells. As the authors write, a curcumin derivative called bi-demethoxycurcumin "displayed the best binding affinity" to spike proteins. It works on a range of viruses, including SARS-1. Turmeric is the plant, and curcumin is the compound found in its roots. Curcumin has demonstrated potent antiviral activity, and remarkably it has shown the ability to reduce viral loads of HIV to “undetectable” levels while also improving CD4 counts.
How much should you take?
The dose runs at 450 mg capsules three times a day, with a concentration of 80 percent curcumin or better. You have to watch out. A number of curcumin supplements are just turmeric power—not strong enough.
Where should you buy it?
Root2 and Kirkland’s turmeric supplements offer the highest concentration I could find, at 960 mg and 1,056 mg of curcuminoids per daily dose. GNC and Puritan’s Pride came in second, with roughly 500 mg.
Several other brands contained the right stuff, but more in the neighborhood of 50-100 mg—just not enough.
Echinacea and/or St. John’s Wort
A 2022 study in Nature found that a mixture of St. John's Wort (hypericum perforatum) and Echinacea showed significant antiviral activity against Covid. Specifically capsules with .9 mg of St. John's "can significantly reduce SARS-CoV-2 viral load," peaking at 36 hours after the start of treatment.
St. John's Wort works fine on its own, on a range of viruses. The authors stress the importance of maintaining its concentration if you add other compounds like echinacea.
How much St. John’s Wort and where do you buy it?
An older 2016 review from Consumer Lab recommends 900 mg of a concentrated extract with .3 percent hypericin and 1-3 percent hyperforin. They recommend Gaia Herbs, Perika, and Medi Herb. They don’t recommend other brands, not even popular ones like Now, the Vitamine Shoppe, or Swanson.
How much echinacea should you take?
For echinacea, the clearest study I found cites 4,000 mg a day of Echinaforce as the effective dose. Strangely enough, Consumer Lab didn’t approve Echinaforce because it only contained .18 mg of polyphenols per capsule. You generally want double digits, at least for this supplement.
Where should you buy it?
Vital Nutrients, Nutrilite Immunity, or BulkSupplements.com.
These brands contain roughly 18-50 mg of actual echinacea per daily dose. Vital Nutrients did the best, with about 25 mg per 500 mg capsule, or 50 mg per daily dose. Some brands don’t stack up very well. For example, Nature’s Bounty only contained 4.7 mg per 400 mg capsule. Don’t even bother with brands like Herb Pharm or Gummiology.
If participants in studies have to take 4,000 mg of a weak supplement like Echinaforce to squeeze out a few mg of echinacea, then you probably wouldn’t have to pop higher quality pills all day long. With the standard daily dose, you’re getting as much or more than described in the studies.
You might even do okay with Nature’s Bounty.
Warning:
Supplement sites mention side effects with extended use beyond eight weeks—especially on your liver. So echinacea might be something you use during high-risk times and then give yourself a break.
Elderberry
A 2022 study reviews available research on elderberry (sambucus nigra), confirming antiviral activity against HIV, flu, and coronaviruses. As the researchers write, adults in clinical trials "showed a significant reduction in symptoms, averaging 50 percent." Elderberry has also shown the ability to stimulate the production of immune cells. A 2019 study confirms that elderberry works against flu via "multiple modes of therapeutic action," including the inhibition of replication and host cell entry. An extensive 2021 study looking at prior research found that high-quality elderberry extracts enriched with anthocyanin work especially well.
How much should you take?
Things get complicated with elderberry. You can test any given supplement for anthocyanins, the specific compounds like quercetin and rutin found in elderberry. But when you add other nutrients like zinc or Vitamin C, it muddles things a little by upping the total polyphenol count. So it’s hard to know exactly what you’re getting. The clearest study I found on elderberry identifies BerryPharma as the brand used. One 300 mg capsule contained 22 percent polyphenols and 15 percent anthocyanins. The rest was rice flour. So when you take 300 mg of elderberry, you don’t need 300 mg of anthocyanins to get the job done.
At 15 percent, you need about 45 mg.
Where should you buy it?
Popular brands like Sambucol or Whole Foods 365 advertise 150 mg of elderberry but they only contain .2—.3 mg of anthocyanins per tablet. Sambucol at least shows 58 mg of polyphenols, so you’re getting something antiviral.
If you want the best, brands like New Chapter’s Elderberry Force offer the most actual anthocyanins, at 69.3 mg per dose.
The rest barely crack 1 mg.
Olive Leaf Extract (Oleuropein)
A 2024 study found that oleuropein, found in olive leaf extract, demonstrates high antibacterial activity at 130 mg/ml and high antifungal activity at 65 mg/ml. Another 2022 study found that oleuropein showed significant effectiveness against Covid in hospitalized patients when they were given 250-500 mg every 12 hours for five days. (No real difference between 250 and 500 mg.) The study also reviews previous research that oleuropein has shown effectiveness against other viruses, including HIV and influenza. It works the same way as other flavonoids, lectins, secoiridoids, and polyphenols, by blocking ACE2 receptors.
How much should you take?
For olive leaf extract, the clearest study I found used 98 percent pure oleuropein developed by the Department of Veterinary Medicine at the University of Tehran, at 500-1000 mg per day. So when you buy olive leaf supplements, you want the highest concentration you can get.
Where should you buy it?
So go with Swanson, Solaray, GNC, or Nature’s Way.
Swanson’s 250 mg capsules contain 100 mg of actual extract—the best I could find. The other brands hover around 40-50 mg, which ain’t too shabby (all things considered). To achieve the doses described in studies, you’d need to take at least three Swanson capsules and five or six capsules of other brands like Solaray.
That might feel… dicey.
Agencies like Consumer Lab aren’t shy that you often have to take charge of doses to see the intended effects. Still, we’re sort of on our own here, and that can get dangerous. If you’re going to experiment, you might want to do it before you fall desperately ill with avian flu—to see what your body can tolerate during normal operating conditions.
Oregano
Oregano (origanum vulgare) extract demonstrates antiviral activity against many DNA and RNA viruses, including Covid and HIV. As researchers have found, oregano extracts "showed remarkable efficacy against equine influenza virus, canine coronavirus, RS, and H1N1. In fact, it can inhibit up to 74 percent of viral activity at certain sites. Again, carvacrol does the heavy lifting.
Consumer Lab hasn’t evaluated oregano oil capsules as far as I can tell, but this article reviews several studies endorsing its use as a broad antibiotic and antiviral. It recommends 600 mg per day. When you’re looking at brands, pay attention to how much carvacrol it offers.
Warning: Oregano oils and supplements are potent. Like some of the others listed here, pay attention to duration and taper off after 2-3 weeks. This one can also interfere with medications.
So, talk to a doctor first if you’re already taking something.
(Honestly, good advice in general.)
Cinnamon
According to the clearest study I could find, two tablespoons of cinnamon get the job done. It needs to be Ceylon cinnamon. With so many brands out there, it’s easy to pick something that’s adulterated or even toxic. Even Simply Organic cinnamon contains higher amounts of coumarin, a toxin.
(Stay away from Badia.)
Store brands like Whole Foods 365 made the cut for quality and safety. So did McCormick’s (It’s Cassia, not Ceylon, but still okay). As for supplements, go with Swanson, Nature’s Bounty, or Puritan’s Pride. If you’re shopping for cinnamon, I would buy something clearly labeled Ceylon.
Consumer Reports has also identified brands of cinnamon to stay away from, and which ones are okay. They’ve said store brands like Good & Gather, 365, Kirkland, Trader Joe’s, and Great Value are okay.
Garlic
According to studies, you need 600 mg of garlic for 150 days to fight viral persistence, and you need 300 mg for another 150 days. So, that pretty much means garlic every day to benefit from any antiviral properties. Lab tests look for the presence of allicin, with one gram of garlic delivering 1,000 mg of virus-fighting compounds. One gram of garlic looks like a grain of rice.
So, it doesn’t take much.
Where should you buy it?
Brands like Nature’s Way, Life Extension, and even Garlique all deliver on their promises. You can also just eat garlic.
The same goes for ginger.
Kudzu Root & Radix Bupleuri
Studies have found antiviral potential in kudzu root. Even before the pandemic, a study in Retrovirology found that kudzu root extract fought HIV infection by inhibiting cell entry and could be added to a patient’s existing medicines. Kudzu contains puerarin, a compound that’s already used to treat diabetes, Parkinson’s, and cancer. A 2022 study in Frontiers in Immunology found that puerarin offers potential for Covid patients not only through its antiviral properties but also by moderating the immune system’s inflammatory response.
A 2020 study identified puerarin, along with quercetin and kaempferol, as very effective antiviral and immune system treatments. A standard dose of puerarin lands at 200-400 mg per day, but one study on kudzu root for heart problems used 400-600 mg per day for up to 15 days.
The traditional Chinese herb Radix Bupleuri contains puerarin, quercetin, and kaempferol. It has shown strong antiviral effects against a range of diseases, and it’s been used for thousands of years.
The standard dose comes in at 3-10 grams per day. You don’t want to go over that amount, because like goat’s rue, it’s toxic in higher doses.
It’s hard to find brand recommendations here.
Let me know if you have info.
Vitamins & Minerals
The best vitamins and minerals to fight pathogens include B, C, D+K2, and zinc. The best vitamin brands in general include Thorne, GNC, New Chapter, Life Extension, Kirkland, Now, Solaray, and Doctor’s Best. Common store brands like Swanson, Now, and Nature’s Bounty also generally do very well. Swanson routinely shows up as a top pick. My family also uses Mary Ruth’s liquid vitamin drops, and Consumer Lab has given them a thumbs up on zinc and vitamin C.
These brands don’t always outperform every time on everything, but it’s good to have a list of contenders to start with instead of just cruising through the internet without any sense of what’s trusted and what’s not.
Metformin & Goat’s Rue
A 2024 study at the University of Minnesota found that metformin (derived from goat’s rue) significantly reduces viral load in patients while lowering the risk of rebound and Long Covid. That study confirms another one in 2023 that saw metformin reduce the risk of Long Covid by 41 percent.
Here’s the dosage they describe:
500 mg on day 1, 500 mg twice daily on days 2–5, then 500 mg in the morning and 1000 mg in the evening up to day 14.
It’s worth noting that metformin was originally developed in the search for antivirals against malaria and flu, so the recent studies make sense.
So, it’s a flu medicine.
You can’t get metformin without a prescription, but you can buy goat’s rue, also known as galega (after the scientific name galega officinalis). It’s been used for centuries as a medicine, much the same way doctors prescribe metformin now. The recent studies on galega’s antiviral potential focus on guanidine, a compound found in plants that works like polyphenols and flavonoids.
Warning: Goat’s rue can be fatally toxic if you take too much. Metformin replaced early compounds like buformin and phenformin for this exact reason. So you’ll want to be careful with that one. A study in Molecules explains that goat’s rue becomes toxic in foraging animals at .8 grams per 1 kilogram of body weight. The standard dose in alternative medicine comes in at 4 grams per day. In order to reach toxic doses found in livestock, a 140 lb person would need to take around 50 grams. A little math shows that the average recommended goat’s rue dose (4g) exceeds the amount of metformin used to treat Covid patients.
Other Supplements
We have other supplements that need more exploration:
A common spice called artemesia annua demonstrated antiviral activity in clinical trials. The group who took an artemisia compound called artemisinin-piperaquine "took significantly less time to reach undetectable levels of SARS-CoV-2 than the controls." In fact, artemisinins "are known for their extended-spectrum antiviral activity." An artemisia derivative called artesunate has shown effectiveness against both DNA and RNA viruses including hepatitis and HIV.
So it works on a range of viruses.
Artemesia compounds work similar to ginkgo by latching on to five different parts of the spike protein "which might explain its remarkable binding affinity." In addition to flavonoids like quercetin, researchers have identified di-caffeoylquinic acid as doing a lot of the heavy lifting here. Like curcumin, these flavonoids also bind to ACE2 receptors on your cells and protect them. Medical researchers are working on refining these compounds into artenimol, a single high-potency compound for giving to patients.
There’s also nigella sativa (black cumin seeds) have shown antiviral activity by disrupting viral RNA transcription. Carvacrol and nigellidine extracted from these seeds "can block ACE2 receptors, thus inhibiting the SARS-CoV-2 entry into the host cells." Then there’s ginger (6-gingerol, 8-gingerol, 10-gingerol), which can inhibit parts of the Covid spike protein. Specifically, it's the bioactive compounds geraniol, shogaol, zingiberene, and zingiberenol that do the blocking.
Dandelion extract has shown to be "effective against influenza virus infection" and in higher concentrations "showed efficacy against spike proteins... and its different mutants" in human lung and kidney cells, while also helping to prevent the cytokine storm that's often so deadly in the acute stage.
So, that’s four more antivirals on the list.
Final Thoughts
So, that’s a lot of information to keep straight.
Here's a chart:
The studies linked in the sheet provide the most detailed dose information I can find. Duration runs around two weeks for an acute illness and 3-4 months for chronic infections. It's important to talk with a doctor if you're skeptical or not sure about interactions with other drugs, or you can look at the studies on your own. Supplements in general can be hard on your liver and kidneys, especially if you take them for prolonged periods.
You can also look at Stephen Harrod Buhner’s Herbal Antivirals and Herbal Antibiotics. These plant compounds work the same way as many of the antivirals on the market. Medical researchers have been researching the antiviral properties of plants for decades, and cultures have used them for thousands of years. Given our current outlook, they're worth taking seriously.
If you plan on diving into supplements, it’s worth signing up with Consumer Lab for their full data. You can also look for a certificate of analysis (COA), awarded by NSF or USP, who provide similar types of testing and approval. I’ve been combing these websites for the last day and they’re pretty amazing. You can look up most of these supplements and extracts on Mount Sinai's health library. You can also visit sites like Drugs.com to start gathering information. Both sites give excellent information on possible side effects and drug interactions. In particular, some Long Covid survivors have noted that supplements with quercetin lower blood pressure, so if you’re already taking treatments related to blood pressure or cardiac issues, you definitely want to talk to a doctor first.
The US Pharmacopeia (USP) has a long history that predates the FDA. Unfortunately, the 1994 Dietary Supplement Health and Education Act essentially made quality and safety standards voluntary. Since then, companies can basically do whatever they want as long as they don’t put “USP” on their labels. Fortunately, the USP still offers a verification program. So if you’re not sure about a supplement, then at least you have these safeguards. You’ll also want to become friends with the FDA’s page on supplements, while it’s still up.
Do I think it's sustainable to take high amounts of supplements all year long to ward off all kinds of airborne diseases, for the rest of our lives? Not really. But with public health frozen and a fascist regime breathing down our necks, we need all the help we can get. You can find all the studies here.
Use what you can. It’s not magic.
It’s science.
Thanks for the post and the chart. It's exciting that people are getting back to what was once known and valued. Many of us in UK have been using andographis and also UK traditional herbal bitters to good effect for a while. Turmeric is my fave all-round powerhouse. Chuck garlic and ginger in and that's dinner sorted - curry is king! It's great to be building our knowledge together. Thanks for this hard work.
That looks interesting. I used to forage wild edibles so this definitely looks like something I should check out, especially given that I have grave concerns about the integrity of our healthcare system under MAGA. Thanks for posting.