Understanding and doing the low histamine diet
Histamine is not the enemy. You need histamine, but you don’t need lots of it getting trapped in your body.
The low histamine diet is a histamine-in-histamine-out scenario​​ to reduce incoming histamines from food. You will work with your practitioner to ensure optimal histamine elimination and reduce production, but the diet only deals with significant food sources of histamines.
Ingested histamine in the digestive tract is broken down primarily by diamine oxidase (DAO). If your DAO enzymes are insufficient for the amount of histamine you’re generating (genetic factors or not eliminating effectively), histamine builds up and causes symptoms.
NOTE: Do not go on a low-histamine diet if you are pregnant or breastfeeding without practitioner guidance.
The main objective of the low histamine regime is to tip the histamine balance so it does not build up and cause symptoms. We work on this from a few angles:
- Reduce incoming histamine (low-histamine diet)
- Reduce stored and circulating histamine
- Downgrade mast cell activity to limit histamine production
Things to watch out for that may thwart you
Medication and antibiotics
Some medications stop your ability to break down and eliminate histamines. The main culprits are alcohol, antacids and NSAIDs (painkillers), but some antibiotics block the DAO enzyme, as do many common medications. Most only do it for a short time.
If you’re on long-term medication, check this post for which block the DAO enzyme temporarily​2​.
Probiotics
Do not take any probiotics except those listed as histamine-friendly. This includes vagina-friendly probiotics!
Stress and anxiety
It might seem impossible if you’re super stressed, but make some serious attempts to calm your nervous system using stress-reduction strategies (herbs, massage, meditation, singing, riding your bike) to lower the stress hormone cortisol.
Stress hormones destabilise mast cells which is bad news for histamine levels.
If the diet or supplement regime is just too hard for you at the moment, that’s ok – talk to your practitioner and explain what is challenging for you so alternatives or workarounds can be found.
Gut problems (SIBO, IBS, Crohn’s, colitis, celiac)
If you have a problem with digestion or your intestines, it could contribute to your ability to process histamine. Work with someone (naturopath, functional medicine doctor, gastroenterologist) to get your issues properly diagnosed and controlled.
History of disordered eating/orthoplexia/very low body weight
If the strict diet is not on the menu for you, try the supplement regime by itself. You can learn about the foods and avoid the highest-histamine foods in a pared-down version of the diet if that suits you better. Get in touch for help.
Nutrient deficiencies
Nutrient deficiencies can exacerbate mast cell activation and histamine release/mast-cell destabilisation, so ensure you get what you need here. It is wise to check your multivitamin and other supplements to ensure sufficient intake during this experiment.
People high in histamine often have genetic mutations that thwart detoxification pathways (MTHFR, DAO, COMT, CBA).
– Vitamin D
Vitamin D stabilises mast cells, with deficiency linked with activation of mast cells (more histamine production)​3​. About 2,000IU per day is suitable.
– Zinc
Zinc regulates mast cell function​4​, so ensure adequate intake (15mg zinc picolinate per day with food if you are not already taking any in other supplements – check labels, don’t overdo it).
– Selenium, vitamin C
Selenium​5​ and vitamin C​6​ stabilise mast cells. Vitamin C levels are often directly correlated to blood histamine levels, so even just taking high-dose vitamin C for several days can decrease histamine (3,000-5,000mg in divided doses across the day).
Selenium is in meats, brazil nuts, cottage cheese, rice, brown rice, sunflower seeds. About 55mcg per day is required.
– Quercetin, bromelain
Quercetin and bromelain also have a mast-cell stabilising effect, as you’ll see in many of your supplement ingredients.
– Vitamin B6 (Pyridoxine)
DAO depends on sufficient B6, so ensure this vitamin is somewhere in your vitamin collection. 2mg per day should be sufficient.
– Magnesium
Low magnesium increases histidine decarboxylase activity – the process of converting histidine into histamine. If you don’t eat many leafy green vegetables, get eye twitches or muscle cramps, or are unsure if you’re low, take a good-quality magnesium supplement. About 400mg or 500mg per day is enough.
– Copper
Copper is a cofactor of DAO, required for DAO production, though without a test, we don’t tend to supplement copper. Good sources of copper are nuts, seeds, leafy green vegetables and dark chocolate. We need about 1mg per day.
– Manganese
Manganese inhibits histamine release from mast cells, though we don’t typically need to supplement with manganese. Foods high in manganese include whole grains, nuts, soybeans, legumes, rice, leafy green vegetables, coffee, tea and black pepper.
Herbs that can help
While not nutrients, some herbs can stabilise mast cells and reduce histamine levels – almost all histamine-regulating products contain one or more of these herbs and nutrients.
Herbs like holy basil, peppermint, ginger, thyme and turmeric work well and can be added to foods and drinks. Nigella sativa, nettle and baical skullcap are also used medicinally.
