LOW HISTAMINE DIET

What is a low histamine diet?

A low histamine diet aims to restrict foods that are high in histamine. This typically starts with a two to four-week trial period. High-histamine-content foods can then be slowly reintroduced one at a time to test histamine tolerance. Foods high in histamine include alcohol, cured meat, salmon, tuna, bananas, oranges, grapes, fruit juices, dried fruits, and fermented foods, including yogurt. However, histamine content is highly variable in various food products.¹ Alternatives low in histamine include non-citrus fruits, fresh meat, fresh fish, and dairy substitutes such as almond milk.

How can a low histamine diet help alleviate certain long COVID symptoms?

Histamine is a chemical that is released by mast cells during an infection and leads to an inflammatory response. It is suggested that COVID causes mast cells to over-release histamine, resulting in inflammatory effects that can lead to long COVID symptoms. Histamine is naturally present in various foods, and by ingesting foods with less histamine, it is believed that this can reduce the inflammatory effects from long COVID.² 

What evidence supports the use of a low histamine diet for long COVID?

More research is being done to investigate the benefit of low histamine diets for long COVID symptoms; however, more studies currently need to be supporting its use. Anecdotally, several case reports have noted success and improvement of long COVID symptoms with a low histamine diet.³ It is important to note that this may only be the case for some long COVID patients. Given its difficulty in application, a doctor or dietitian should carefully consider a low histamine diet to weigh the risks and benefits for an individual.

What are some things to watch out for with a low histamine diet?

It is recommended that you have a dietitian provide support while starting a low-histamine diet and ensure that you are safely following it without the risk of nutritional deficiencies. The low-histamine diet is time-consuming and difficult to follow for many; thus, you should not start one if it may cause greater fatigue or negative impacts on your mental health. 

References:

1)      Diet & long COVID recovery: anti-inflammatory vs low histamine. Vitality360. Accessed November 3, 2023. https://www.vitality360.co.uk/blog/2022/04/05/diet-amp-long-covid-recovery-anti-inflammatory-vs-low-histamine

2)      Anderson E. Caution advised with low histamine diets for long COVID. BDA: The Association of UK Dietitians. May 20, 2021. Accessed November 3, 2023. https://www.bda.uk.com/resource/caution-advised-with-low-histamine-diets-for-long-covid.html

3)      Schofield JR. Persistent antiphospholipid antibodies, mast cell activation syndrome, postural orthostatic tachycardia syndrome and post COVID syndrome: 1 year on. EJCRIM 2021;8. doi:10.12890/2021_002378