WHAT IS 'HISTAMINE'?
Histamine is a biologically active amine that is involved in immune responses, most well-known for its involvement in allergic reactions. We release extra histamine when the immune system is triggered by a perceived external threat (allergen). Histamine then travels through your blood, causing blood vessels to dilate, resulting in an 'inflammatory response', such as those experienced in hay fever i.e. runny nose, itchy eyes, red, puffy face or hives. However, it also acts as a neurotransmitter like serotonin and dopamine. Histamine is involved in the wake-sleep cycle and is required for arousal, alertness, learning and memory. It also regulates appetite, other neurotransmitters and the perception of pain. Antihistamine medication is typically taken in cases of allergies to calm and reduce this histamine response. In many cases though, this is a temporary fix.
Histamine is not bad. It is essential, and balancing histamine can be the key to managing your symptoms.
Mood disturbance/Neurological: irritability, depression, brain fog, anxiety, vertigo, tinnitus, headaches/migraines, insomnia and unexplained fatigue.
Skin: rashes, flushing, hives, eczema, tissue swelling Inflammation: joint pain and stiffness
Cardiovascular: palpitations, high blood pressure, irregular heartbeat, racing heart.
Gut symptoms: diarrhea/constipation, abdominal pain & cramps, IBS symptoms, nausea, food intolerances, reflux/GORD or heartburn, bloating after meals.
Allergies/Hay fever: nasal congestion, sinusitis, post-nasal drip, chronic cough, sneezing, trouble breathing, asthma.
Reproductive/Hormonal: abnormal menstrual cycle, pre-menstrual symptoms, period pain, oestrogen-driven conditions, hot flushes.
How does Histamine build up?
Histamine is released from specialised immune cells known as mast cells. Histamine can also appear in certain foods, so factors that contribute to elevated levels of histamine production or intake can be:
Allergies or food intolerance Bacterial overgrowth - e.g. SIBO/Dysbiosis Leaky gut or gut bleeding/damage Histamine-rich foods/fermented foods Genetics (issues with DAO enzyme function)
Histamine is naturally broken down by an enzyme: DAO (diamine oxidase). This is produced in a healthy intestinal lining. However, if there is damage to the intestinal lining, DAO activity can be reduced. Damage to the intestinal lining commonly occurs with microbiome imbalance, bacterial or parasitic infection, food intolerances, constipation, poor diet and too much alcohol. DAO also has an interesting relationship with cortisol, one of the hormones we release in response to both acute and chronic stress. As cortisol rises, it can lead to inhibition of the action of DAO.