What is the latest on inflammation and histamine, vitamin and mineral supplements?
Inflammation and histamine
The British Dietetic Association (BDA) released a statement – Low histamine diets and post-COVID syndrome [PDF] – after growing reports of people using a low histamine or similar types of diets.
They noted:
- Histamine in the body is high to support and defend our bodies against infections (such as COVID-19), and this can cause a wide range of symptoms including bloating, diarrhoea, nausea, headache, rhinitis, wheezing, hypotension, arrhythmia, urticaria, itching, flushing and fatigue.
- There is a lack of consensus whether foods high in histamine make this situation worse.
- There is a lack of evidence on whether avoiding histamine in the diet works for patients with post-COVID syndrome.
- There are anecdotal reports that it can improve symptoms which may mean some patients may wish to try it.
- Anyone interested in trialling a low histamine diet, should not follow it for more than four weeks without the support of a registered dietitian to minimise any associated risks.
For more information, you can watch Professor Philip Calder's talk, Is there an anti-inflammatory diet?
See also our Supporting COVID-19 recovery: operational challenges page for further information.
Vitamin and mineral supplements
To date, it is unknown if over-the-counter vitamins and supplements in general are helpful, harmful, or have no effect on the treatment of ongoing symptoms of COVID-19 (Cawood et al., 2020; Louca et al., 2021).
For other chronic health conditions similar to post-COVID syndrome and/or for people with underlying conditions affecting vitamin intake, supplements are recommended only when food fortification or food only are not sufficient for the person’s requirements, which should be assessed by a dietitian or appropriately trained healthcare professional (Calder, 2020; NICE, PHE and SACN, 2020)
Several studies have shown a relationship between some nutrients and recovery.
There may be a possible role of vitamin D in the prevention and treatment of COVID-19, however, there is no evidence yet that supplementation is necessary or beneficial, except in those who have a proven vitamin D deficiency.
A serum vitamin D test is required to diagnose vitamin D deficiency.
A supplement of 400IU is recommended for all adults in the UK during the winter months between September and March (NHS, 2020; NICE, PHE and SACN, 2020).
A Korean study found those deficient in vitamin D and Selenium to be at higher risk of severe complications (Benarba and Khaled, 2021).
Vitamin D deficiency however, does not alter the immune system significantly or differently than for other infections (Rodriguez-Leyva and Pierce, 2021).
Achieving vitamin K levels seems particularly relevant for COVID-19 recovery given the use of antibiotic across some patients which may decrease vitamin K pool, which is important for the gut’s microbiota (Segal et al., 2020).
This systematic review provides a range of evidence about the most common phytochemicals, micronutrients and nutraceuticals of interest for the treatment of COVID-19. (Ayseli et al., 2020).
The following herbal and plant components have been studied to assess their benefits to immunity: Curcumin, beta Glucan, Selenium, Astaxanthin, Ceruloplasmin, Myeloperoxidase, Quercetin, Resveratrol, Asplenium montanum (Naidu, Pressman and Clemens, 2021).
There is very little and weak evidence to support the use of these supplements to support COVID-19 recovery.
Supplements can potentially cause harm as well as benefit (Patel, Martindale and McClave, 2020), therefore it is advised to monitor response to any new supplement, take it for a fixed period of time and ideally introduce one supplement at a time.
If you think your patient needs assistance in fortifying their diet, discuss this with a dietitian.