Is Long Covid due to an immune system that has failed to return to normal after Covid 19 infection? What you need to know from our Specialist Nutrition
Post-Covid illness, or Long Covid, has become part of the new landscape of the pandemic. So much is still unknown and its effects are wide and diverse, but the most common symptom is fatigue. Research is at an early stage, with little on diet.
Is Long Covid due to an immune system that has failed to return to normal after Covid 19 infection? What is the role of inflammation? What about food intolerances, such as histamine?
Having good nutrition, so that your body has all the nutrients and energy it needs, is an important part of recovery from illness. For some, Covid 19 may mean difficulty in eating and significant weight loss. This depletes energy and nutrition stores, causing muscle loss and malnutrition, at a time when you need extra energy and nutrition to recover.
Malnutrition not only happens to those who are underweight but potentially anyone who has had a severe or prolonged illness that affects their eating.
1. Are you suffering from malnutrition?
Check if you are likely to be suffering from malnutrition, and work at improving this. There are some highly-rated self-screening tools, which are widely used by medical, health and social professionals. One is the MUST tool. If you are concerned for yourself, or for a family member or friend, try the Patients Association Nutrition checklist.
Depending on the level of eating problem and weight loss, your doctor may refer you to a dietitian for extra support.
The NHS “Your Covid Recovery” has the advice to help you to boost nutrition and energy when your appetite may be poor or affected by changes to taste and smell. There are tips for nourishing meals and snacks and how to increase your protein and energy intake. Some people may need, and be prescribed, oral nutrition supplement drinks to achieve an adequate intake by their doctors.
2. What is an anti-inflammatory diet?
An anti-inflammatory diet is also known as the Mediterranean type diet. This diet best supports the immune system which, which when working well, controls inflammation in the body. The body’s immune response is highly complex and involves the significant construction of new cells, such as proteins and antibodies. This needs raw ingredients, like protein, fats and energy; also co-enzymes and many different vitamins and minerals. To achieve this wide range of different nutrients this anti-inflammatory or Mediterranean type diet needs a wide range of diverse foods, such as many colourful plant foods, including vegetables, fruit, nuts, pulses and seeds, whole grains. Omega 3-rich foods, such as oily fish or vegetarian alternatives, are recommended. This diet is low in highly processed high sugar fast foods and snacks, and high in fibre. This is also very similar to the “Eatwell Guide” diet recommended in the NHS “Your Covid Recovery”.
3. Is the gut microbiome important?
There is emerging evidence about the importance of healthy gut bacteria for our health and therefore, potentially, for Covid 19 recovery. The gut microbiome consists of trillions of bacteria that live in our gut. The latest research indicates that they may have a far-reaching role in our physical and mental health. To improve our gut microbiome
• Eat a diverse, wide range of different fruit, veg, pulses, beans, nuts, seeds
• Increase fibre intake (aim 30g day)
• Thirty different plant types a week over the full spectrum of colour
• Probiotics and Prebiotics
• Fermented foods, kefir, kombucha
4. What about histamine intolerance?
Histamine is produced by our body to fight off viruses and infections. It also occurs naturally in some foods and there have been some reports of success using a low histamine diet for Long Covid.
The theory proposes that some people with Long Covid may have excess blood levels of histamine, triggered by the Covid 19 virus and dysfunctional MAST cells (MAST Cell Activation syndrome). Histamine intolerance symptoms include headache, asthma, runny or blocked nose, low blood pressure, irregular heartbeat, hives, itching, diarrhoea, flushing and other conditions.
Symptoms can occur after a few hours up to a few days after eating foods high in histamine. These symptoms are similar to those reported by some people living with Long Covid. A small number of doctors have used a low histamine approach for Long Covid and some report success. However, it is not known how many may benefit and certainly will not be helpful for all. More research is needed.
As yet, there is no test that can diagnose histamine intolerance. It is not a food allergy; therefore, food allergy testing is not helpful. The best way to investigate histamine intolerance is to avoid high histamine foods for approximately 2-4 weeks, then to gradually reintroduce to assess tolerance. This should be under the supervision of a registered dietitian to ensure that it is followed safely and to minimise the risk of nutritional deficiencies.
It is also advisable to have a clinical assessment with a medical doctor. Ideally, one who is experienced in histamine intolerance (or Mast Cell Activation Syndrome). They can consider other tests to exclude other conditions.
5. How challenging is the low histamine diet for sufferers?
Most people with Long Covid have significant fatigue and, therefore, it can be very challenging to prepare and cook for a low histamine diet, especially as fresh food is advised in preference to ready-made food. This diet also restricts some foods recommended for the gut microbiome, so, for long-term health, it is important to test toleration of histamine foods rather than avoid them altogether.
6. Why work with a dietitian?
A dietitian can assess your food diary and advise if you may benefit from a trial of a low histamine diet. It is important to work with a dietitian, as the low histamine diet can be limiting and may lead to nutrient deficiencies if followed for long periods.
A dietitian will ensure adequate nutrition during the restriction phase and support when re-introducing foods. Some individuals may be able to tolerate a certain amount of histamine in their diet after a period of time.
7. Want to learn more about Nutrition and Covid recovery?
A series of free talks are available now to share advice on the best nutrition to aid recovery, www.bda.uk.com/resource/free-talks-to-share-how-nutrition-can-aid-covid-19-recovery.html
It is hosted by the University of Plymouth, with funding from the British Dietetic Association. The talks are open to everyone, especially people who have or are living with, the effects of COVID-19, and their carers.
Co-organised by University College London, Bournemouth University, Imperial College London, and NHS Greater Glasgow and Clyde, the talks address questions such as:
Is there an anti-inflammatory diet?
Is there a link between food and my symptoms?
So in summary, taking care of your nutrition and eating well will help your recovery from Covid illness. The basis of a healthy diet for recovery is to have a wide variety of plant-based foods including fruit, veg, pulses, beans, nuts seeds, good fibre intake, regular omega 3 foods and only a few processed foods and snacks.
Sue Luscombe. RD Vitality360 Nutrition and Diet Consultant