Quercetin supplements have been getting attention as a possible treatment for coronavirus. It sounds incredible but legitimate researchers in both Canada and China are investigating this right now. In this review, you'll learn about the quercetin nutrient and the interest researchers have for it is a natural anti-viral supplement. Quercetin seems to work against other viruses so, in theory, there may be something to this. Let's look at the research. Remember, nobody is yet saying this is a cure or vaccine. The best defense is what you already know – washing hands and self-isolating.
What Is Quercetin
Quercetin is a polyphenol plant nutrient called a flavonoid. Quercetin is actually the most abundant flavonoid found in foods. It's a well-known antioxidant and has other effects too such but not limited to:
- raising nitric oxide levels
- lowering LDL bad cholesterol
- reducing inflammation
- helping lower blood pressure
Quercetin in Foods
Foods containing the quercetin nutrient include:
- red onions
- red grapes
- red wine
- broccoli and kale
- Black tea and green tea
How much you get from food would depend on what your diet was like. While there's no RDA for this nutrient, people usually get 10-100 mg per day. If you want to know which foods contain the most, that would be capers and lovage as they some of the highest amounts with 180mg per 3oz. While that's a good amount, to compare, you'd have to eat over 6 pounds of apples to get the amount found in some supplements.
For wine lovers, 25 oz of red wine has just 14 mg, so not very much.
Quercetin Antiviral Effects
In a test tube, quercetin inhibits HIV virus replication. The nutrient also seems to inhibit poliovirus replication too. In addition, other research has noted quercetin may reduce influenza A infection. This means the nutrient may act as a broad-spectrum anti-virtual agent.
Remember, the research on the antiviral effects of quercetin is preliminary at this stage and human studies need to confirm this. Nobody is calling this is a vaccine or cure. The results are mostly based on lab animals and isolated cells. What is not known is whether quercetin supplements reduce viral infection in people. Still, studies like these appear to give hope that this readily available nutrient may be effective against other viruses too.
Can Quercetin Prevent Coronavirus
That is the big question. The man at the head of this is Canadian researcher Dr. Michel Chrétien. He started looking at quercetin after the Ebola outbreak back in 2014. He observed the nutrient appeared to protect mice when given it before infection. His team later found the supplement helped lab animals infected with the Zika virus too. When the coronavirus started to get out of control he started to wonder if quercetin may help slow the spread.
To know for sure, it will take human clinical research. That research is underway now.
Dr. Chrétien is working with doctors in China to see what happens when 1000 people infected with coronavirus are given quercetin supplements. The results of this study are not yet reported. Right now we don't know if it prevents infection or helps the recovery of those who are infected.
How Does It Work?
The antiviral effects of quercetin appear to work in two different ways:
- preventing the coronavirus (and other viruses) from entering cells.
- helping the body be better able to fight off the viral infection
How Much Do You Take?
There is no official dosage yet. In a TV interview, Dr. Chrétien mentioned taking the supplement 4 times a day. But, if it really works, what is the best dosage? That is not yet known.
1 Does it work better with bromalin
Bromalin is a plant enzyme that has anti-inflammatory effects, just as quercetin does. The idea is for both to be better at reducing inflammation than either would alone. When it comes to virus infection, quercetin – by itself – has been used in animal studies.
2 What food has the most?
Lovage and capers have the highest amounts but this is still less than found in a single quercetin supplement.
3 Is it the same thing as CoQ10?
No. Coenzyme 10 (CoQ10) is a different supplement. Some of their effects are similar, however. CoQ10 has not been tested to see if it's a natural antiviral compound.
4 Is it the same as rutin?
They are similar to each other. Rutin is basically quercetin bound to a sugar molecule. Whether rutin supplements would also have antivirus effects needs to be tested.
5 How long does it stay in the body?
It may depend on how much you took. In one human study, a 1000 mg supplement took 17 hours before levels returned to normal.
6 How much do you take?
It is not known how much works against the virus – or even if it does work. Many supplements contain 250-1000 mg per one or two capsules. Its anyone's guess if the best dosage is in that range or more. When taking any new supplement, using less for the first week is usually a wise choice. Right now nobody is saying the supplement is a cure. That's important to remember.
7 The unknowns
There's a lot we still don't know about how the supplement interacts with the virus. For example:
- does it work better in women or men?
- can it cure people who already are infected?
- does it work better when combined with medications?
- what's the best amount to take?
Please DO NOT start taking quercetin supplements and stop washing your hands, disinfecting surfaces, and maintaining a good social distance from others. These other things WILL work.
8 Is it safe?
The supplement has been around for a long time. Most healthy people have no ill effects. Some research, involving isolated cells, has hinted the nutrient may cause cancer in high doses but human studies have not shown this. Ironically, some human investigations hint it may protect against cancer.
Quercetin Side Effects?
The good news is the supplement has been around for many years and has a well-known safety profile. Most people have no or mild side effects. Here is a general list of things to consider. This list is not complete:
- start with less for the first week to see if you have any side effects
- some people have reported headaches.
- the supplement may lower blood sugar and blood pressure
- the supplement may interact with various medications
- stop taking at least 2 weeks before having surgery
- if pregnant or nursing, ask your doctor
- interactions with other dietary supplements may also be possible
How to increase absorption
Quercetin is not well absorbed. Some research suggests bioabsorption is better when it's combined with sugar. Other research suggests bioabsorption increases when it's combined with phytosomes. Phytosome are basically plant fats that are attached to a compound. In this case, the compound would be quercetin.
There are many quercetin phytosome supplements available. Right now there is no best brand to use.
Does It Realy Work?
It's too soon to tell if it's a treatment or not. Previous studies tell that quercetin seems to have antiviral effects against SARS, influenza and other infectious diseases. But, human proof is lacking. At this stage of the game, we don't know if it works but studies are ongoing. Even if it does work, this is not a substitute for social isolation, washing hands, and other important things to stop the pandemic. On the plus side, quercetin is not expensive and has few side effects.