Histamine, Zonulin, And DAO: A Complete Guide
- Josh Boughton
- Jun 12
- 9 min read
Histamine, Zonulin, and DAO are becoming more well-known because an increasing number of people are finding out that histamines are more than just a problem with seasonal allergies. They can affect everything from gut and skin health to immune function and more.
What are Histamine, Zonulin, and DAO?
Histamine is a chemical that helps to communicate messages to your brain, triggers the release of stomach acid for digestion, and is released after injury or allergies as a part of your body's immune response.
Some histamine is beneficial, but excessive amounts can lead to problems.
Too much histamine can cause a number of unpleasant effects, such as headaches, nausea, congestion, and watery eyes. It can lead to more serious conditions, such as ulcers.
Excess histamine also causes a number of gut health issues and can make certain conditions, such as IBS, much worse.
DAO, diamine oxidase, is an enzyme produced in your kidneys, thymus, and intestinal lining that helps to break down histamine. Without enough DAO, histamine can begin to accumulate in the body.
Zonulin is a protein that regulates intestinal permeability. Zonulin modulates the permeability of tight junctions between cells of the wall of the digestive tract. Our bodies need some zonulin, but excessive amounts can lead to problems.
"Leaky Gut" is a term commonly used to describe problems with the gut lining. What it really is is a symptom of a larger problem in the gut. It happens when the tight junctions in the gut lining start to come apart, allowing things to leak into the bloodstream that should not be there. We believe a more accurate term for this is tight junction dysfunction. Zonulin plays a huge role in this process. Elevated zonulin levels contribute to a loosening of the tight junctions.
The small intestinal villi help to absorb nutrients and provide digestive secretions. If there are problems with your gut lining, the villi will be negatively affected. Zonulin plays a vital role in the health of your villi.
What is Histamine Intolerance?
Histamine Intolerance is a condition that can affect the ability to metabolize histamine, and often, there is overproduction of histamine. People with this disorder tend to have much lower levels of DAO in the body. DAO plays a big role in regulating the amount of histamine in the body. It’s essential for people with histamine intolerance to follow a low-histamine diet. It can be a challenging diet to follow, so working with a dietitian who understands histamine intolerance is important.
Foods that support healthy histamine, DAO, and Zonulin levels
To ensure optimal DAO levels, the following nutrients are especially beneficial:
Vitamin C
Copper
Vitamin B6
Phosphorous
Magnesium
Zinc
Iron
B12
Eating lots of whole foods rich in these nutrients is a great way to support healthy DAO levels.
Beef and lamb liver is an incredibly nutrient-dense food and is rich in so many nutrients that support healthy DAO levels, including:
B-12
Zinc
Iron
Copper
Phosphorous
Ensure you obtain grass-fed liver that was processed and frozen shortly after harvest. Here is a great source. If eating liver is not for you, grass-fed liver capsules are an easy option. As with making sure your liver was processed and frozen soon after harvest to prevent it from being high in histamine, your beef liver capsules should be quickly processed and freeze-dried. Unfortunately, most companies don’t make their own raw materials or beef liver capsules, so they are often quite old when you get them, leading many people to think they cannot tolerate liver capsules, when in reality, it is just poorly made liver capsules causing problems for them.
Vitamin C is so important for healthy DAO levels and histamine metabolism. While many foods rich in vitamin C are high in histamine, there are a number of options that are low in histamine and high in vitamin C:
Mangos
Broccoli
Apples
Bell Peppers
Blueberries
Apricots
Cranberries
Peaches
If you are not getting enough vitamin C rich foods in your diet, a real, low-histamine, whole food vitamin C supplement is a great option. Unfortunately, many vitamin C supplements labeled as whole food are not. Check out our blog to learn more about how to choose a whole food vitamin C and spot the fake ones.
Magnesium is very important for healthy DAO function in the body. Most people do not get enough magnesium in their diet. Here are some low-histamine, magnesium-rich foods:
Sprouted pumpkin seeds
Sprouted almonds
Sprouted chia seeds
Macadamia nuts
Cooked kale
Wild-caught salmon
Buy frozen seafood, not from the seafood counter or canned, to ensure it is low in histamine.
Having adequate B12 levels helps to support healthy DAO activity. These foods are rich in B12, while being low in histamine:
Eggs
Milk
Beef
Lamb
Buffalo
Elk
Venison
Beef Kidney
Wild-caught frozen fish
Ensure meats are quickly frozen after butchering and not aged, to minimize histamine levels. White Oak Pastures is a great source of low-histamine meats.
Copper is crucial for maintaining healthy DAO function. Here are some great low-histamine copper-rich foods:
Beef liver
Sprouted pumpkin seeds
Sweet Potatoes
Wild-caught frozen salmon
Getting enough zinc in your diet will help a lot to improve DAO function in your body. It is also very important for a healthy gut lining. Here are some great low-histamine, zinc-rich foods:
Sprouted pumpkin seeds
Beef liver
Beef
Elk
Venison
Bison
Buffalo
Lamb
Goat
Mutton
Vitamin B6 helps to support the healthy production of DAO in the body. Here are some great low-histamine B6-rich foods:
Sprouted oats
Milk
Ricotta
Eggs
Beef liver
Kidney
Sweet potato
DAO Rich Foods
There are only a few foods that are rich in DAO.
Pea shoots are one of them. These little guys are an excellent way for those who are low in DAO to get some from their diet. You can grow your own pretty easily. We don’t recommend buying them at the store because they often sit for too long or are grown in conditions that are too warm, which can significantly reduce the levels of DAO.
Beef kidney is packed with DAO. It is also rich in vitamin A, B12, B6, and selenium, which are important nutrients for healthy histamine metabolism. Here is a great source for it. If eating kidney is not for you, grass-fed kidney capsules are a great option.
Foods that reduce histamine
Having excess levels of histamine in the body is a miserable experience, as anyone who has allergies can tell you. There are some foods that can help support healthy histamine degradation.
Onions, garlic, shallots, and leeks not only make food taste delicious, but they are also some of the best foods for histamine metabolism. Onions are especially rich in quercetin. Quercetin is a flavonoid found in certain plants with a variety of helpful properties.
While they may be famous for a not-so-great reason, fava beans are one of the richest food sources of quercetin.
Watercress is a potent antioxidant, rich in vitamin C, and a natural antihistamine. This food is one of the most potent histamine-fighting foods.
Apples are rich in quercetin and other flavonoids that help to reduce histamine levels. The peel is especially rich, so don't throw it away. Red and golden delicious apples have lower levels, so it would be best to choose other varieties.
Pomegranates are another great choice for healthy histamine levels. Eat the seeds, not the juice. You can buy the seeds frozen if you don't want to fight with the whole fruit.
Ginger and turmeric help to support healthy cytokine and histamine levels. Cook them with some fat like ghee for the best effect. It's best to use fresh ginger and turmeric if possible. Grate them for maximum benefit. As a base for sautes, cook onions, garlic, ginger, and turmeric together in ghee for a powerful punch.
Peppermint is an excellent herb for supporting healthy histamine levels. Make a tea using fresh peppermint for the most potent effect. Steep it covered for ten minutes before drinking.
Foods that support healthy zonulin levels
Maintaining zonulin levels within a healthy range is crucial for supporting gut lining health. Some foods shine in supporting this goal.
Bone marrow is rich in collagen, healthy fats, and much more. This is one of the most nourishing foods for your gut lining. Make sure to use bones from grass-fed animals. If you're having trouble finding them near you, here's a great source. This incredibly delicious and nourishing food is fast and easy to make. If eating bone marrow is not for you, then properly made grass-fed bone marrow capsules are a great option.
Tripe and intestines are rich in protein, collagen, the amino acid glutamine, and many other important nutrients for gut health. Some of these, cooked in some low-histamine bone broth, will provide potent nourishment for your gut. If you cannot find grass-fed tripe and intestines near you, here is a great source. If eating tripe and intestines is not for you, grass-fed intestines and tripe capsules are a great option.
Homemade applesauce is rich in pectin. This pectin helps to soothe and hydrate an irritated gut lining. Here is an easy recipe:
Slice apples, leaving the peel on.
Just cover with water and simmer until the apple peels get very shiny.
Strain the apples.
Mash or puree until it reaches the desired consistency.
Place in single-serving jars and freeze.
Just two tablespoons per day is all you need, but you can have more, of course. This simple food is one of the best for supporting a healthy gut lining.
Bone broth is excellent for gut lining health, but most of it is very high in histamine due to how it is made and stored. It is rich in collagen, gelatin, and a host of other beneficial compounds. Here is a great recipe for low-histamine bone broth. Freeze it in single-serving glass containers for a warm, nourishing broth whenever you need it. If making bone broth is not for you, you can use low-histamine bone broth powder.
Hydration and Histamine
Being dehydrated will significantly increase the levels of histamine in your body. Make sure you are drinking plenty of water or eating lots of water-rich, low-histamine fruits and vegetables.
Stress and histamine
Stress plays a significant role in the metabolism of histamine. Chronic uncontrolled stress can lead to an increase in histamine levels. Check out our blog for lots of great tips on how to manage stress.
Sleep and histamine
Poor sleep quality can drastically affect histamine levels. Check out our blog for lots of great tips to help you sleep well.
Supplements that support healthy zonulin, DAO, and histamine levels
There are a number of supplements that can help support healthy histamine levels. Keep in mind that it can take time for them to kick in and start working at their full potential. Just like with other supplements, ensure you take these daily for at least three months and at the correct dosage to yield the best results. Consistency is key. As with other supplements, it’s a good idea to speak with your healthcare practitioner before starting them.
First up is IGY. IGY are immunoglobulins that are derived from special chicken eggs.
They work to support the entire gut environment, making it more hospitable to beneficial bacteria and promoting the healthy production of DAO and maintaining healthy zonulin levels. IGY works gradually, with the effects building over time. So make sure to take it every day. It can be mixed with any cold food or beverage.
Next up is Beef Kidney. Beef Kidney is one of the richest food sources of DAO. DAO is the enzyme that helps to break down histamine in the gut. It is also rich in selenium and B6, which are important nutrients for supporting healthy DAO levels. Beef kidney is packed with nutrients, including:
Vitamins A, B2, B3, B5, B6, B9, B12
Phosphorus
Selenium
Zinc
Iron
Copper
It is best taken before meals and snacks.
Histamine and Immune is made with grass-fed grass-finished regenerative farmed beef thymus, beef lung, beef spleen, beef liver, and beef kidney. It contains a unique combination of nutrients, peptides, and compounds, including:
Thymopoietin and Thymulin from Thymus.
Thymosin fraction five and thymosin alpha-1 peptides
Thymosin beta-4
Thymic humoral factor
Diamine Oxidase (DAO) from kidney
Kidney-Specific Peptides
LEAP-2 peptide from liver.
Hepcidin Peptide Splenin, Tuftsin and Splenopentin from spleen
Ergothioneine Peptide
Vitamins and Minerals:
A, D ,E, K2 (as mk-4)
B2, B9. B12, B3, and choline
Copper, heme iron, selenium, and zinc
CoQ10
Gut and Digestion is made with grass-fed bovine liver, pancreas, spleen, intestine, and stomach (tripe). It contains a blend of important nutrients and compounds that help to nourish and support the gut.
Vitamins
A, D, E, K2 (as mk-4), b12, and niacin
Minerals
Heme iron, selenium, and zinc
Tripe
Collagen, enzymes,
BP-157 peptide
Intestines
Collagen and glutamine
Spleen
Hepcidin Peptide, Splenin, Tuftsin, and Splenopentin
Alkylglycerols
Pancreas
The richest food source of pancreatic enzymes.
Amylase - Starch digestion
Protease - Protein digestion
Lipase - Fat digestion
Liver
Leap-2 peptide
Choline
A nutrient most people don’t get enough of, which plays a crucial role in digestion. Choline helps the body utilize and transport lipids, is an important food source for gut bacteria, and supports healthy gut motility.
Think of Gut and Digestion as a whole food multivitamin for your gut.
It’s crucial to know that when using beef organ supplements that you choose those are made from fresh organs that the company gets directly from the farms and processes right away, because many beef organ supplements are made from bulk powders that have been sitting in warehouses for long periods of time, which can lead them to be high in histamine, which is the last thing you want if you are dealing with histamine issues.
Check out our blog to learn more about what to look for when choosing a beef organ supplement.
Histamine, DAO, and Zonulin Questions and Support
If you have questions about our DAO, histamine, and zonulin supporting supplements, please email us at info@rooted-nutrition.com, and we will be happy to answer them!
