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Can Quercetin Help Heal a Leaky Gut?

by Kelsey Kinney, RD

Last updated on

quercetin leaky gut, quercetin histamine
Quercetin, a nutrient found in foods like these apples, is great for healing leaky gut.

Digestive health is a hot topic these days. Problems in the gut not only play a large part in digestive issues like irritable bowel syndrome or reflux, but the gut has an effect on practically every part of our body.

Imbalances in the gut can create rashes, exacerbate joint pain and even cause depression – it’s no wonder we all want to learn how to keep the gut healthy!

One of the most pressing concerns regarding the gut is something called intestinal permeability, often referred to as “leaky gut”. The barrier of the gut plays an important role in maintaining our health by protecting us from the many things we’re exposed to from the outside world. If you think about it, our digestive tract is technically not “in” our body, it’s outside.

Think about your body as a donut and the digestive tract is the donut hole – technically, not “in” the donut. It’s easy to see now that our gut lining is exposed to everything we swallow – food particles, bacteria, dust, etc – and has to decide what to do with all that material! Think of the gut barrier as the decision-maker: some particles are allowed to pass through, while others are told to move on through.

When functioning normally, the gut barrier keeps us healthy by keeping out potentially hazardous materials and letting nutrients and water in. But when it starts to become more permeable (or “leaky”) than normal, we run into problems.

Of course one of the most important things for preventing excessive intestinal permeability is to eat a Paleo diet that works for you (a la Your Personal Paleo Code; The Paleo Cure in paperback). However, there are definitely other nutritional components that can help, quercetin being one of them!

Mast Cells = Leaky Gut?

Researchers have discovered that mast cells play a part in developing leaky gut. While it’s been known for a long time that severe physical stress (i.e. trauma or surgery) causes intestinal permeability, newer research has shown that chronic stress also has this effect. (1) Interestingly, researchers determined that it is the mast cells in the intestine that are responsible for the increase intestinal permeability in these stressful situations. (2)

You may have heard of mast cells before as the cells responsible for allergy symptoms like congestion, runny nose, etc. This is because when mast cells “degranulate” or become “unstabilized”, they release histamine, the chemical that causes allergy symptoms. But you have mast cells in your gut, too and when they “degranulate” or become “unstabilized” there, they cause leaky gut.

Quercetin for Leaky Gut

Quercetin is one of the most abundant flavonoids present in our food supply, found in high amounts in onions, kale and apples. (3) It is well-known for many things, including its anti-allergy properties, anti-cancer effects, and as an antioxidant. But did you know that it can heal leaky gut, too?

Given that intestinal permeability is caused (at least in part) by unstabilized mast cells in the gut, it makes sense that quercetin would have this effect. This is because quercetin stabilizes mast cells and prevents the release of histamine and other chemicals from these cells. (4) When researchers breed rats to have no mast cells in the gut (thus they are unable to have unstabilized mast cells that release histamine), they no longer develop intestinal permeability. (5)

Quercetin has also been shown to enhance gut barrier function by having a “sealing” effect due to its role in the assembly and expression of tight junction proteins. (6) Tight junctions regulate our intestinal permeability by connecting intestinal cells, thus only allowing the nutrients that we need in and keeping everything else out.

In rats given DSS (a substance that causes colon damage), treatment with quercetin restores barrier integrity and partially heals colitis. (7) Rats given another substance to cause colitis and treated with quercetin preserved normal fluid absorption (which is altered by colitis), counteracted glutathione (our “master antioxidant”) depletion and ameliorated colonic damage at two days. (8)

I’d say that’s some pretty good news for those suffering from leaky gut!

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Quercetin in the Diet

Now that we know quercetin is healing substance for a leaky gut, how do we get enough?

Well, the good news is that on a Paleo diet, you should be getting quercetin by eating your fruits and vegetables. Remember that a Paleo diet can, and for most people, should be a diet high in fruits and vegetables, which naturally contain quercetin. But if you’d like to add some extra quercetin to your diet (or you can’t tolerate many fruits and vegetables), a quercetin supplement is also an option.

There is limited data regarding the amount of quercetin in our food, but below are the estimates available. (9) Your best bet is to just eat a wide variety and a lot of plant matter for optimal intake and consider supplementation if needed.

  • Fruits: 2 – 250 mg/kg
  • Vegetables: 0 – 100 mg/kg (onions are especially high at 200 – 600 mg/kg)
  • Tea: 10 – 25 mg/L
  • Fruit juice: 2 – 23 mg/L
  • Red wine: 4 – 16 mg/L
It’s also important to note that other flavonoids such as naringinen seem to have similar healing effects on leaky gut, so including a wide variety of plant matter to increase your intake of many different polyphenols is a great idea. (10) Not to mention that polyphenols improve your gut bacteria, too!

Here’s the take-home message: eat your fruits and veggies for your daily dose of quercetin, or consider a supplement if you can’t tolerate much plant matter or if you’ve got a severely leaky gut. If you’d like to go the supplement route, aim for 800 mg twice a day or 400 mg three times a day for a total of 1,200 – 1600 mg per day. It’s very difficult to get these levels from food, so a supplement is a good choice.

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Chris Kresser in kitchen
Kelsey Marksteiner
Kelsey Kinney, RD

Kelsey Kinney, RD, is devoted to helping the world achieve great digestive health through her blog, private practice, and prebiotic & probiotic drink mix company Gut Power Drinks. Check out her blog, Gut Power Drinks website, or visit her on Facebook for more.

Kelsey is a registered dietitian specializing in digestive and hormonal health. She graduated from New York University with a Bachelor of Science degree in Nutrition and Dietetics and went on to complete her dietetic internship at Milford Regional Medical Center in Milford, Massachusetts. She also has a Master of Science degree in Human Nutrition and Functional Medicine from the University of Western States.

Kelsey loves helping people find their unique, personalized diet that will help them heal, not anyone else. She has always been interested in nutrition and health, and is honored to now help people find a diet that brings them happiness and longevity.

Professional website: https://kelseykinney.com

Gut Power Drinks website: https://gutpowerdrinks.com

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Join the conversation

  1. Just wanted to say that it’s my understanding that oral quercetin supplements largely have horrible bioavailability issues. There are some new forms on the market using isoquercetin and isoquercitrin that are trying to help address this.

    All that said, there are some rich food sources, notably capers, that could go a long way in boosting levels with an all natural form of this promising compound. Think capers have something like 180mg quercetin per 100g, plus they’ve get a load of other stuff in them, including rutin.

    • I’m having success with isoquercitrin. No comparison to the standard quercetin. And since the absorption rate is much higher, the supplemental has less overall mg per capsule.

  2. It would seem after a little while of using Quercetin with Vitamin C, that the Quercetin is cuasing a flush like reaction, similar to Niacin. Why would this be? I mix my vitamin c and quercetin in a water bottle and drink it off/on during the day. I noticed this flush when I had both vitamin c and quercetin together. Next day only Vitamin C, no flush. Today I added quercetin and I’m getting some minor flush like reaction.

    • I read a study yesterday showing that quercetin when used in conjunction with Vitamin C acted as an MAO inhibitor, but when taken alone, it did not. So maybe the flushing is due to elevated serotonin.

    • I also experience flushing symptoms from Quercetin- no vitamin C or other ingredients added…

  3. Hi everyone,
    If you have allergies, you may want to seek out Bioset/N.A.E.T. These are allergy treatments that are holistic and work very well. My family and I had suffered for many years with allergies. The polyphenols that are naturally in food, you can be allergic too, including quercetin. For years I would wake up and have a stuffy runny nose, cleared the a certain phenol that relates to the sinuses, now I do not have that issue anymore! Polyphenols are the first things that the therapists clear(make sure they clear each one by name, not as a group), then moving onto vitamins and minerals(again, make sure they clear each one by name not as a group), then they can clear you of other things. If you decide to take quercetin supplements, and you feel worse, you could have an allergy to it. (It could also be the way they processed it or the other ingredients they use).

  4. I want to reduce or eliminate my osteoarthtitic pain and overall health.
    Also, the way I get more fruits and veg (especially) veg in my diet is by reducing or eliminating grains, dairy, and sugar. That leaves me with meat and veg or starve!

  5. On histamine issues of Mast Cell Activation Syndrome, onions is one of the primary triggers for some folks. I love onions and garlic, but, def have symptoms of a leaky gut which started/was caused by emotional trauma. My sense tells me that healing the lining would relieve the sensitivities, histamine reactions I now experience.

    If the effect is modest I would think the benefit outweighs the negative. Any input or thoughts?

    • Hi the only issue I had with quercetin when I tried it is that it extends adrenaline in the body and lowers blood sugar, and for Me, that’s not good. I didn’t sleep well and I got a lot of heat from the adrenaline insulin sea saw. I have since developed chronic gastritis (1 year later) and excess histamine issues and so am trying to find a solution, and am considering trying quercetin again. Perhaps a lower dose might help, or else taking it with progesterone cream, which inhibits adrenaline I believe? Anyway I’ll let you know how I go.

      • I was reading recently about histamine and the article suggested using the enzyme DAO that breaks down histamine. I think it is called DAO Histame. Hope this info helps you.

  6. Hi, For years i took zyrtec anti-histamines to stabalise mast cells. It turns out that they also, and rather alarmingly, reduced stomach acid. I then ended up with significant digestive issues and then SIBO. I know that the effect of antihistaines on stomach acid has been researched and documented. I have just purchased TwinLabs Quercetin thinking this ‘natural’ alternative would be better. However, now i am wondering if even natural anti-histamines/mast cell stabalisers will have the same impact on stomach/digestive acids and enzymes? Thanks so much. Sonia