DAO Supplement for Histamine Sensitivity

OmneDiem® produces a family of Diamine Oxidase (DAO) enzyme dietary supplements formulated to support the body's natural histamine breakdown process in the digestive tract.* Each product in the OmneDiem Histamine Digest® family is built around DAOgest® — a naturally derived, porcine-sourced DAO enzyme with an established safety and activity profile in the published scientific literature — and delivered in a designed-release capsule technology formulated to activate in the small intestine, right where dietary histamine is processed.*

Whether you are looking for everyday pre-meal support, a higher-potency formulation, broader histamine coverage that includes seasonal respiratory and sinus support, targeted support during the menopausal transition, or a convenient option to take before consuming alcoholic beverages, OmneDiem offers a DAO enzyme supplement formulated for your specific needs.

What Is Histamine

Histamine is a naturally occurring compound found throughout the human body and in many common foods and beverages. In the body, histamine plays important roles in immune function, digestion, and neurological signaling. It is produced by the body's own cells and is also present in elevated amounts in many fermented, aged, cured, and processed foods. If you would like to learn more, the National Institutes of Health maintains an extensive body of peer-reviewed research on histamine and its physiological effects.

What Is Histamine Sensitivity?

Histamine sensitivity is a term used alongside Histamine Intolerance in the scientific and clinical literature to describe a condition in which the body may have difficulty managing the amount of histamine arriving from dietary sources. It is generally understood as a mismatch between the amount of histamine entering or being produced in the body and the body's capacity to break it down through enzyme activity.* WebMD describes histamine intolerance as distinct from a true histamine allergy, noting that it involves the body's reduced ability to degrade histamine rather than an immune-mediated allergic response.

Histamine sensitivity or intolerance is not classified as a disease and is not a true food allergy. It is a functional condition associated with reduced activity of Diamine Oxidase (DAO), the body's primary enzyme for breaking down dietary histamine in the gut.* Because histamine intolerance shares characteristics with other conditions, including food allergies, irritable bowel syndrome, and seasonal sensitivities, it is frequently misidentified. If you believe you may be experiencing histamine sensitivity, consult a qualified healthcare provider for proper evaluation.

What is the difference between Histamine Sensitivity or Histamine Intolerance and a Histamine Allergy?

A true histamine allergy involves the immune system's IgE-mediated response to a specific allergen and can be life-threatening in severe cases. Histamine intolerance is not an allergy and does not involve an IgE immune response. Instead, it is associated with a reduced capacity of the digestive system to break down histamine from food and drink before it is absorbed into the bloodstream.*

The American Academy of Allergy, Asthma, and Immunology provides foundational public health information on immune responses and the distinction between allergic and non-allergic physiological reactions.

Consult your healthcare provider to discuss your medical history and determine the most appropriate course of evaluation if you suspect food allergies, intolerances, or sensitivities.

What Causes Histamine Intolerance?

Histamine Intolerance, or HIT,  is understood in the published research literature to be primarily associated with reduced activity of the DAO enzyme, which is produced naturally in the lining of the small intestine and is responsible for breaking down histamine from food and drink before it can be absorbed.*

Factors that may be associated with reduced natural DAO enzyme activity include individual genetic variation, advancing age, hormonal changes, including those occurring during perimenopause and menopause, certain medications, including some NSAIDs and antibiotics, alcohol consumption, and alterations in gut health and the gut microbiome.*

A secondary enzyme called Histamine N-Methyltransferase, or HNMT, also plays a role in managing histamine within cells throughout the body, and reduced HNMT activity may also be associated with histamine sensitivity in some individuals.*

What is DAO?

Diamine oxidase, commonly referred to as DAO, is an enzyme the body produces naturally in the lining of the small intestine. Its primary biological role is to support the breakdown of histamine in the foods and beverages you consume before it can be absorbed into the bloodstream. When the body's natural DAO enzyme activity is reduced, dietary histamine may accumulate in the digestive tract and potentially be absorbed into circulation, where it may interact with histamine receptors found throughout the body. 

Foods and beverages high in histamine

Foods and beverages commonly associated with elevated histamine content include aged and fermented cheeses, cured and processed meats, smoked fish, canned fish and seafood, fermented vegetables like pickles, fermented soy products, vinegar-based condiments, alcoholic beverages, particularly red wine and craft beer, and certain fruits, including citrus, strawberries, tomatoes, and avocado. Some foods may also be associated with the release of histamine already stored in the body's cells, known as histamine liberators, potentially adding to the overall histamine load in the gut.*

When the body's natural DAO activity may be insufficient to support the breakdown of histamine from these dietary sources, a range of experiences may occur that vary widely among individuals and are generally dose-dependent in nature.* These experiences are not specific to any single diagnosable condition. If you experience symptoms that concern you, consult a qualified healthcare provider.

What is a DAO supplement?

A DAO dietary supplement supplies diamine oxidase enzyme to support the body's natural histamine breakdown process in the digestive tract.* When taken before consuming high-histamine foods or beverages, a DAO supplement may support DAO enzyme activity in the small intestine, where dietary histamine is absorbed, potentially supporting the body's natural histamine management process before histamine enters the bloodstream.* 

Can I take a DAO supplement? 

Some individuals explore DAO supplementation in consultation with their healthcare providers as part of their overall approach to supporting healthy histamine management.* Factors that may be associated with reduced natural DAO activity include advancing age, hormonal changes, including those occurring during perimenopause and menopause, certain medications, alcohol consumption, and alterations in gut health and the gut microbiome.* To learn more, the National Institutes of Health maintains published research on DAO enzyme activity and its relationship to histamine sensitivity.

How do DAO supplements work?

OmneDiem's® Histamine Digest® DAO supplements are designed to be taken before consuming high-histamine foods or beverages. The enzyme acts locally in the digestive tract and is not absorbed into the bloodstream, meaning it supports the body's natural histamine management process within the gut, designed for maximum effectiveness.* A designed-release capsule formulation, such as those used across the OmneDiem Histamine Digest product family, is specifically engineered to protect the delicate DAO enzyme from stomach acid and deliver it intact to the small intestine, where it may support the breakdown of dietary histamine.*

Do not open or crush designed-release DAO capsules, as doing so may reduce their effectiveness.

What is HDU and why does it matter?

HDU stands for Histamine Digesting Units and is the standardized measurement of DAO enzyme activity or potency in a dietary supplement. HDU values reflect the enzyme's capacity to support histamine breakdown under standardized laboratory conditions, making HDU a more meaningful measure of supplement potency than milligram weight alone.* When comparing DAO supplements, the HDU count is the most relevant indicator of enzymatic activity per capsule.*

OmneDiem produces a family of DAOgest® based diamine oxidase dietary supplements formulated to support the body's natural DAO enzyme activity.* DAOgest is a naturally derived, porcine-sourced DAO enzyme with an established safety and activity profile in the published scientific literature. All OmneDiem Histamine Digest products use a designed-release capsule technology formulated to activate in the small intestine, where dietary histamine is processed.*

OmneDiem Histamine Digest ®

60 or 120 capsules with 30,000 HDU (Histamine Digesting Unit) of Histamine Neutralizing Enzyme. Gluten-free, non-GMO, soy-free, non-dairy, food-grade Diamine Oxidase - with no artificial preservatives or sweeteners.

OmneDiem ® Histamine Digest PureMAX ®

60 Capsules supplies 40,000 HDU of pure DAOgest DAO enzyme per designed-release capsule with no added excipients beyond ultra-purified microcrystalline cellulose, formulated for those who may benefit from greater DAO enzyme support per capsule.*

OmneDiem ® Histamine Complete ®

120 or 60 Capsules combines 30,000 HDU of DAOgest DAO enzyme with additional ingredients formulated to support healthy seasonal respiratory and sinus function alongside dietary histamine management, making it the only OmneDiem product designed to support both dietary and environmental histamine pathways in a single capsule.*

OmneDiem ® Histamine Digest Menopause Complete ®

30 Capsules combines 30,000 HDU of DAOgest DAO enzyme with Estro8PN, flaxseed lignan extract, black cohosh, and citicoline to support the body's healthy response to the natural changes occurring during menopause and to support natural histamine levels and processing, which may be associated with hormonal fluctuations during the menopausal transition.*

OmneDiem Drink HD® supplies 30,000 HDU of DAOgest DAO enzyme per designed-release capsule in a portable 20, 60 or 120 count tube formulated to support the body's natural histamine management when taken before consuming alcoholic beverages, which are among the most common high-histamine dietary exposures and which may also be associated with reduced natural DAO activity.*

Histamine Digest product line

Additional Resources

*These statements have not been evaluated by the Food and Drug Administration. OmneDiem dietary supplements are not intended to diagnose, treat, cure, or prevent any disease or health condition. This content is for general educational and informational purposes only and does not constitute medical advice. References to third-party sources including the National Institutes of Health, Centers for Disease Control and Prevention, WebMD, and Cleveland Clinic are provided for informational and educational context only and do not imply endorsement of OmneDiem products by those organizations. Individual results may vary. Consult your healthcare provider before beginning any new supplement regimen, particularly if you are pregnant, nursing, taking prescription medications, or managing a health condition. OmneDiem Histamine Digest products contain a porcine-derived ingredient and are not suitable for individuals with pork allergies or those following vegetarian, vegan, kosher, or halal diets.

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