At first glance, the immune system and thyroid disease may not seem to have much in common. However, research suggests that an important element of immune activity, histamine, and a thyroid condition called Hashimoto’s thyroiditis may be related.
What is Histamine?
The immune system is composed of many elements. One widely employed component being a chemical called histamine.
Histamine is released as part of the body’s reaction to allergens. Histamine promotes better circulation, digestion, neurological communication, and initiates protective inflammation. Additionally, histamine encourages smooth muscle contraction and blood vessel dilation, which eases white blood cell transport to the impacted area. These are all beneficial in managing an allergen assault. However, excess histamine may result in various issues including the development of histamine intolerance.
Histamine intolerance occurs when histamine production outpaces the body’s ability to remove it. This can be caused by chronic exposure to allergens or histamine buildup. A key component of histamine intolerance is diamine oxidase (DAO). DAO is an enzyme produced in the digestive tract that helps metabolize and breakdown histamine. Increased histamine production in conjunction with depressed DAO values or activity results in DAO-histamine imbalance and subsequent histamine intolerance.
Histamine intolerance causes vague, non-specific symptoms similar to those experienced during an allergic reaction. Symptoms may include:
- Reduced blood pressure
- Runny nose
- Stomach cramping
Perhaps the most damaging quality of histamine intolerance is that it demands sustained immune activation. Chronic activation of the immune system makes it more prone to malfunction. Such errors can result in a wide range of health issues including chronic disorders like Hashimoto’s thyroiditis.
The Link Between Immunity and Hashimoto’s
When working properly, the immune system is highly effective at keeping the body safe. It accomplishes this through a process of identification and elimination. However, if the immune system is overworked, stressed, or malfunctioning it may begin to target healthy cells and tissue. In the case of Hashimoto’s, the immune system wrongfully identifies thyroid tissue as dangerous.
As the body’s own defenses begin to attack the thyroid, its function declines. The decrease in thyroid activity results in a condition called hypothyroidism. Hypothyroidism is accompanied by a general slowing of bodily function and symptoms including fatigue, weight gain, and difficulty thinking clearly – get a full list of thyroid disease symptoms here. Hashimoto’s patients may also experience symptoms associated with hyperthyroidism, or excess thyroid activity, such as anxiety, heart palpitations, shakiness, and diarrhea. This occurrence, known as Hashitoxicosis, is caused by the release of thyroid hormones when thyroid tissue is destroyed.
Any sort of stress placed upon the immune system can result in a worsening of Hashimoto’s. Because histamine intolerance encourages overactivation and exhaustion of the immune system, it is considered by some to be a major contributor to Hashimoto’s.
The Shared Contributors of Histamine Intolerance and Hashimoto’s
When it comes to treating disorders relating to immune dysfunction, such as histamine intolerance and Hashimoto’s, identifying and resolving contributing factors is critical. If an underlying contributor remains undiscovered or unresolved, the existing disorder is almost assured to remain. Some of the most common underlying causes of histamine intolerance and Hashimoto’s are discussed below.
Gluten is a protein found in grains that can damage the intestine, trigger immune activity, and prompt the release of histamine. Each of these elements encourage histamine intolerance and contribute to Hashimoto’s.
Intestinal permeability, also known as leaky gut, is a condition that allows allergens to escape the intestine and enter the bloodstream. This results in a sustained allergic response and extended release of histamine.
Small intestinal bacteria overgrowth (SIBO) is a condition wherein bacteria from the large intestine migrate and colonize the small intestine. Certain bacteria commonly seen in SIBO are histamine producers. As these bacteria increase in number so too does the amount of histamine in the gut. SIBO is also commonly seen among those with Hashimoto’s.
IgE food allergies are what most people imagine when they think of serious allergic reactions. Peanuts, shellfish, and tree nuts are examples of IgE food allergies. Those with IgE allergies often have difficulty breaking down histamine, meaning they are more likely to experience histamine intolerance. Furthermore, if a person has an IgE allergy, eating or coming into contact with the allergen can dramatically increase histamine production.
Certain medications can promote histamine intolerance by inhibiting DAO production or encouraging the release of histamine. Possible problem medications include muscle relaxants, narcotics, NSAIDs, antihypertensives, antiarrhythmics, diuretics, laxatives, antibiotics, histamine (H2) blockers, and antidepressants.
Alleviating Dysfunction Through Diet
In addition to attending to the contributors mentioned above, patients may be able to improve overall immune function, limit histamine irregularities, and reduce Hashimoto’s severity by making specific dietary changes.
The first component of a histamine diet is to reduce eliminate foods that trigger immune activity, contain histamine, or encourage histamine production. If you are suffering from histamine intolerance try to reduce or completely avoid consumption of the following foods:
- Bone broth or other products containing collagen
- Canned, smoked, or fired seafoods
- Certain histamine heavy vegetables including eggplant
- Citrus fruits, tomatoes, avocados, and strawberries
- Cured meats
- Dried fruits like apricots, prunes, dates, figs, and raisins
- Fermented foods
- Nuts including walnuts, cashews, and peanuts
- Pickled foods
- Processed foods containing dyes or artificial sweeteners
- Soured and fermented foods
- Specific teas including black, green, and mate varieties
- Wheat germ
The second portion of a histamine-focused diet is to nourish the body with immune-regulating hypoallergenic foods. To support healthy immune function and histamine balance consider including the freshest versions of the following foods in your diet plan:
- Beef, poultry, and seafood
- Coconut oil
- Coconut, hemp, or almond milks
- Foods rich in quercetin
- Fresh fruits like apples, pears, cantaloupe, grapes, watermelon, and mango
- Fresh vegetables like kale, onions, excepting those mentioned above
- Gluten free grains like quinoa, millet, corn, and rice
- Herbal teas
- Leafy herbs
- Olive oil
- Raw cocoa powder
It is important to keep in mind that dietary requirements are different for every patient. To create an optimized immune-balancing diet plan, speak with a knowledgeable doctor or dietician who is familiar with your specific needs.
Healing Hashimoto’s through Histamine Regulation
Histamine is an important part of immune function. Interestingly, research suggests that irregular histamine activity such as histamine intolerance may play a significant role in the development and continuation of autoimmune disorders; specifically, Hashimoto’s thyroiditis. Resolving histamine intolerance, Hashimoto’s, or other immune-related disorder, requires identification and resolution of any and all underlying contributors.
In addition to attending to common contributors, you can support histamine balance and immune function by adopting a hypoallergenic histamine-reducing diet. Take control of your wellness and combat Hashimoto’s by restoring healthy histamine activity and immune function.
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