The Blood Sugar Connection to the Loss of Diamine Oxidase, the Body's Natural Anti-Histamine

Diamine Oxidase or DAO is the body's primary enzyme for breaking down histamine. DAO is produced in the intestinal mucosal lining of the digestive tract. A decrease in diamine oxidase reflects intestinal mucosal damage. See: Diamine Oxidase (Histaminase) - A Circulating Marker for Rat Intestinal Mucosal Maturation and Integrity (1980). Diamine Oxidase as a Marker of Intestinal Mucosal Injury and the Effect of Soluble Dietary Fiber on GastroIntestinal Tract Toxicity after Intravenous 5-Fluorouracil Treatment in Rats (2013). Clinical Significance of Serum Diamine Oxidase Activity in Inflammatory Bowel Disease: Importance of Evaluation of Small Intestinal Permeability (2011).

The intestinal mucosal barrier is damaged by hyperglycemia. Per the 2018 study Hyperglycemia Drives Intestinal Barrier Dysfunction and Risk for Enteric Infection: "Our results mechanistically link hyperglycemia and intestinal barrier function with systemic infectious and inflammatory consequenes of obesity and diabetes." See also: Poor Short-Term Glycemic Control in Patients with Type 2 Diabetes Impairs the Intestinal Mucosal Barrier: A Prospective, Single-Center, Observational Study (2019). According to this study, type 2 diabetics incapable of maintaining stable blood glucose levels are at a higher risk of intestinal barrier injury.

Alcohol is a strong inhibitor of diamine oxidase. The 1999 study Alcohol-Histamine Interactions illuminates this. "At the periphery, alcohol and acetaldehyde liberate histamine from its store in mast cells and depress histamine elimination by inhibiting diamine oxidase, resulting in elevated histamine levels in tissues," the study states, adding: "Alcohol provokes food-induced histaminosis and histamine intolerance, which is an epidemiological problem."

Essentially, alcohol and the foods the majority of people are eating expel diamine oxidase from the body quicker than Agatha Trunchbull tosses a javelin.

The more histamine that builds up in the body, the more easily the anti-inflammatory hormones in your adrenals are depleted. The 1986 study H1 Action of Histamine on Aldosterone and Cortisol Secretion by Perfused Dog Adrenal states "histamine at pathophysiological concentrations stimulates the secretion of aldosterone markedly, and those of cortisol and corticosterone slightly." In addition to histamine overload, our ubiquitous "new normal" lifestyle embodiment includes an exuberance of stress and subsequent caffeine dependency, further stimulating adrenal hormone release.

It doesn't take a rocket scientist to see that this is why we treat allergies and allergic disease with corticosteroids. Is everyone with allergies in the midst of an Addisonian crisis, so to speak? Interestingly, a brilliant 1944 paper I came across named A Study of Addison's Disease: An Investigation of the Chemical Pathology, Diagnosis and Treatment of Adrenal Insufficiency stated: "It has been shown that there is an increase of over 100% in the blood histamine of adrenalectoraised rabbits, and that the blood histamine level of these animals is considerably reduced after the administration of cortical extract. In patient's with Addison's disease not only is the blood histamine considerably greater than in normal persons, but the distribution of histamine between plasma and blood cells also differs... These findings afford some evidence of an anti-histamine function of the adrenal cortex."

Corticosteroid eye drops including prednisolone and loteprednol and even nasal sprays such as Flonase may cause glaucoma and cataract formation. This is because the low cortisol state has tipped to the opposite side of the scale. Excess cortisol induces or (more likely) worsens hyperglycemia, which is very much involved in glaucoma and cataract formation. Unfortunately, there's no balance in the adrenals anymore, no natural homeostasis that once existed in the body. You're either high or you're low. It mimics the physiological and psychological whirlwind of attempting to regulate blood sugar in a diabetic state. Many people end up becoming greatly dependent on corticosteroid medications. See the 2010 paper Lost in the Mist: Acute Adrenal Crisis Following Intranasal Fluticasone Propionate Overuse.

Some things I've been trying:

NaturDAO - a vegan DAO enzyme booster made from legumes. Do not buy the porcine-derived DAO supplements. Naturdao.com goes into further details on the benefits of this amazing supplement. See the 2017 study: Diamine Oxidase from White Pea Combines with Catalase Protects the Human Intestinal Caco-2 Cell Line from Histamine Damage.

Salt. Salt increases your anti-inflammatory, anti-stress adrenal hormone production in the case of adrenal insufficiency or Addison's disease. It is also a magnificent antihistamine. See Effect of an Excess of Salt on Resistance to Histamine in Rats and Influence of Salt Concentration on Histamine Formation in Fermented Tuna Viscera. I use a bit of La Baleine's salt/potassium/magnesium blend mixed with some of their regular salt in my water. Redmond Real Sea Salt is another great option, though I find it doesn't dissolve as well in water. I use this salt daily on food.

I was never a big drinker, but I haven't touched alcohol in the three years since I've been diagnosed. I do miss a glass of red wine at dinner or while celebrating Thanksgiving or Christmas. There's a new, smart invention called the PureWine Wand: Rapid-Action Wine Filter that removes histamines and sulfites from wine without affecting the taste. I was considering using these if I do go back to having a glass of wine occasionally.

Enzymedica's Allerase: I just started taking this. Essentially vegan pancreatic enzymes (depleted in many aka exocrine pancreatic insufficiency) that synergize to act much like diamine oxidase, according to their description.

I've eliminated caffeine intake for now; I may introduce it again at some point in small amounts. Swiss Water decaf is great if I crave coffee. Likewise, I am very vigilant about my stress levels. Life is far too fragile to be functioning in or surrounded by hyper-stimulation and anger. Those in the Dead Poet's Society know to Gather Ye Rosebuds While Ye May.

The glorious lamp of heaven, the sun,

The higher he's a-getting,

The sooner will his race be run,

And nearer he's to setting.