The Situation Right Now
The Omicron variant continues to accelerate the pandemic (with a highest record of 33,406 confirmed COVID-19 cases on the 5th of March, 2022), though previous delay into the Covid-19 endemic phase has since moved forward as the country aims to enter its transition.
With borders announced to be opened on the 1st of April, together with the termination of all restrictions on business operating hours & capacity limits in the workplace and houses of worship, many of us who have experienced the vast spread of Covid-19 cases lately are left feeling both anxious yet hopeful. While we now administer vaccines and 47.4% of the Malaysian population now with boosters (as of 23rd of March, 2022), the solid evidence of an emergence of the new Covid-19 sub-variant Deltacron (recombinant virus that contains elements of both Delta and Omicron) detected in France, the Netherlands, Denmark and in the U.S. serves as another reminder that the Covid-19 pandemic is far from over.
In fact, did you know that complications may arise even after one has recovered from the Covid infection ? — A.K.A Long Covid.
Terms: Long Covid? Long-Haul Covid? Long-Term Covid? Post-Covid conditions? Post-Covid syndrome? Chronic Covid? And finally, post-acute sequelae of Covid-19 infection (PASC). All these names to identify the condition which continues to frustrate the sufferers, the scientist and even adding on fear to those who are concerned of being affected. They are used when a recovered Covid individual experiences persistent symptoms that can range from mild to exhaustive symptoms which may last for weeks, months or longer after the infection.
Long Covid is such a perplexing issue that the US National Institutes of Health (NIH) and the UK National Institute for Health Research (NIHR) had previously announced they would spend US$1.15 billion and £18.5 million (with a second round of funding worth 20million) to fund researches on long Covid.
But what exactly is Long Covid?
The World Health Organization (WHO) defines Long Covid as “ a condition in people who have a history of probable or confirmed SARS-CoV-2 infection usually within three months from the onset of Covid-19, with symptoms that last at least two months.” The symptoms and effects could also not be explained by another diagnosis.
On the other hand, the British National Institute for Health and Care Excellence (NICE) has helpfully divided Long Covid into two categories when signs and symptoms continue or develop after acute Covid-19:
(1) Ongoing symptomatic Covid-19, which includes people with symptoms 4 - 12 weeks following an infection
(2) Post-Covid-19 syndrome, which includes people with symptoms for 12 weeks or more
Based on the latest research, symptoms may persist for weeks, months or even more than a year after a Covid-19 infection. The symptoms can be different from what was experienced during infection and may impact the organs or systems of the body. Sometimes the effect may occur in cycles too, with patients feeling better for a time and then experiencing a relapse of symptoms.
Long Covid can occur even in people who had mild, moderate or even asymptomatic Covid-19 cases. WHO states that anyone who becomes ill with Covid-19 can develop post Covid-19 condition, while current evidence suggests approximately 10-20% of people experience a variety of mid-and long-term effects after they recover from their initial sickness. In fact, according to the Centers for Disease Control and Prevention (CDC) state that “even people who did not have COVID-19 symptoms in the days or weeks after they were infected can have post-COVID conditions”. However, based on National Geographic, the estimated number of people who are susceptible to developing long Covid ranges from 10% to 50% of the cases. This means that in the whole world, tens of millions of people are still struggling with the prolonged effects.
Based on the same report made by National Geographic, long Covid also affects people who only had mild reactions to the virus, including many kids. This can be seen through the report of The UK Office for National Statistics which after surveying half a million children with Covid found that 12.9% (aged 2-11) and 14.5% (aged 12-16) of children were still experiencing symptoms five weeks after their first infection. A Norway study of 300 patients (aged 16 - 30 years) showed that more than 50% of them are still having persisting symptoms for more than 6 months.
A neuroscientist at University College London led a team and found 205 symptoms quantified over time (for 7 months) in a study which comprised more than 3500 people.
Common symptoms of long covid include:
● Fatigue / extreme tiredness
● Shortness of breath / Difficulty breathing
● Cognitive dysfunction
● Brain fog (difficulty thinking or concentrating, poor recall, poor memory etc)
● Post-exertional malaise (symptoms that get worse after physical or mental activities)
Other symptoms described:
● Cough / Dry cough
● Sore throat
● Changes to sense of smell or taste
● Sleep problems (insomnia)
● Muscle, joints and chest pain
● Heart palpitations
● Psychological distress (anxiety, depression, sleep abnormalities)
No clear explanation exists for the diverse symptoms of Long Covid. Studies suggest that it is a multisystem disorder as many people with Long Covid experience problems from multiple organs. Multi-organ effects can affect many, if not all, body systems (such as brain, heart, lung, kidney and skin functions).
One possibility could be due to the protein molecules (fragments of the virus) which can persist for months in the body might disrupt the body in some way. Another potential reason could be due to a disordered immune system post infection which is now attacking the rest of the body (also known as autoimmune conditions), which causes inflammation (swelling) or tissue damage in the affected parts of the body.
The consequences of lingering inflammatory processes after a Covid-19 infection may keep the immune system being alert and continuously stimulate a response despite confirmation of a negative Covid-test. Some data even showed that remission of symptoms can also be related to genetic variations.
Thus, most researchers suspect that one person’s long Covid might be different from another’s as several mechanisms could be at work.
When will I recover?
If you are wondering how long it will take you to feel back to normal, it’s important to understand that recovery is different for everyone. Some make a full recovery within 12 weeks, but some may last even longer. Some find their symptoms feel better on some days and worse on others.
Nutritional impacts from Post-Covid Syndrome
There are many areas of impact from Long-Covid such as disturbances in the central nervous system (CNS), oral health impacts and psychological impacts. However, we would be discussing mainly the nutritional impacts of Long Covid.
Malnutrition is usually already inevitable in patients with Covid-19 due to its effect on the gastrointestinal system, immune system, infection-induced high metabolic activity, fever and decreased oral intake. As many of the symptoms are likely to present as obstacles to adequate food intake (including the ability to shop and prepare meals), overtime this could lead to persistent malnutrition after Covid-19 as well as the loss of muscle mass and strength.
Malnutrition and Covid-induced biological shifts may contribute to Long-Covid symptoms and further deteriorate nutritional status. Malnutrition is also known to have a significant impact on the immune system where the immunological responses are decreased, inflammatory processes are increased as well as altering the gut microbiome.
Combined, these issues can contribute to a variety of long-Covid symptoms too, such as weight loss, muscle weakness, fatigue, brain fog, weakened immunity and disrupted digestive system.
A. Weight Loss
A study evaluating the impact of Covid-19 after clinical remission on body weight and nutritional status in Covid-19 survivors who were managed at home or as inpatients found that nearly 30% of patients lost more than 5% of their baseline body weight. Do note that a weight loss of > 5% is also the same threshold used to diagnose cancer cachexia.
Due to the alterations of smell and taste, fatigue as well as the lack of appetite, this would affect the food intake of not just older or hospitalized Covid-19 patients but patients with mild Covid-19 managed at home may also suffer from malnutrition.
B. Disrupted / Weakened immunity
Based on the UK research and Innovation Organization (UKRI), alterations in many immune cell types often persisted for weeks or even months after Covid infection. Depending on the type of immune cell, it may recover on its own or remain abnormal / with limited recovery even after inflammation has resolved. It may be that some cell types are slow to regenerate, but for others, including some types of T and B cells, something might continue to direct the activity.
Researchers also detected altered levels of cytokines (molecules that help modulate immune responses) in the blood of Covid-19 infected people, suggesting that their immune system is out of balance.
A significant remaining inflammatory response in all patients even 40-60 days post-viral infection was also observed. Proteins that were still affected were associated with the anti-inflammatory response and mitochondrial stress.
Malnutrition also suggests that long-covid individuals may not be getting sufficient micronutrients or macronutrients that are essential to a normal function of the body including the immune system.
C. Disruption of digestive system
In a study of Covid-19 patients who had been discharged for 90 days, 44% reported gastrointestinal symptoms. 24% reported loss of appetite, 18% reported nausea and acid reflux, 15% reported diarrhea. There were also some who reported symptoms such as abdominal distension, belching, vomiting, abdominal pain as well as bloody stools.
Now, one of the areas that we previously covered are the causes of Long Covid. The exact cause of long Covid is not known however people with a less diverse microbiome in their intestines were more likely to have lingering symptoms post Covid-19 infection. At 6 months, people with long Covid are seen to have fewer ‘friendly’ bacteria and a higher number of ‘unfriendly’ bacteria compared to people who have not contracted Covid-19.
Therefore, researchers have theorized that microbiome profiling might help identify the patients who are most at risk in developing long Covid too.
Things we can do
A. Increase calorie intake
Though the types of food are important, one must consume sufficient quantities as well. Low appetite, lack of hunger signals and faster satiation are reported in Covid-19 and long-Covid, hence proper nutrition intake or strategies are important to aid recovery.
Proteins are crucial components of our immune system and aid in the repair of bodily tissues during recovery. The immune system uses proteins that are typically drawn from muscles to be broken down into amino acids to make new proteins.
Protein also aids in the production of a number of hormones and neurotransmitters that affect our mood, learning, and memory. As a result, inadequate protein consumption is associated with irritability, brain fog, and unstable swings.
In order to rebuild muscle mass and strength, equally distributed protein consumption in meals has been found to boost muscle protein synthesis during recovery. Small, frequent meals with a focus on protein are beneficial, especially while appetite is still low. If you're eating less than usual owing to breathing problems, fatigue, loss of taste and smell or other symptoms, you might want to explore additional beverages (such as milk or plant based milk like soy and almond) or an oral nutrition supplement (ONS).
+ Healthy Fats
Healthy fats are both required and advantageous to one's health. Fat is a simple method to boost your calorie intake but it also helps to store energy, insulates the body, and encourages cell development. Monounsaturated fat (MUFA) and polyunsaturated fat (PUFA) are good fats to include in your diet. Avocados, peanut butter, olive oil, and almonds are examples of MUFA, whereas sardines, salmon, flaxseed, chia seeds, hemp seeds, and walnuts are examples of PUFA. Polyunsaturated fats, such as Omega-3 and Omega-6 fatty acids (also known as Essential Fatty Acids) form eicosanoids, which mediate inflammation and impact the body's processes, according to the National Institutes of Health.
According to researchers, brain fog develops after Covid as a result of an inflammatory reaction in the body that leads to neuroinflammation in the brain. Fats also assist in the maintenance of brain function, notably in terms of cognition and memory. Essential fatty acids help to keep the brain healthy and nerve cells functioning properly.
Some studies have focused on omega-3 polyunsaturated fatty acids, reported immunomodulation effects and an improvement of mood disorders, and thus may have the potential to enhance our immunity against COVID-19 with a positive mental impact.
+ Mindful Eating
Mindful eating may also help to connect an individual to their hunger and satiation cues during a meal as the sensory perception and palatable state of food among Long Covid is diminished. Do try to:
● Carefully select ingredients to prepare your meal
● Never skip meals
● Sit at the table and focus on eating without distractions (no phone or TV interruption)
● Try to utilize all sense while eating (using eyes to look at meal, smelling your meal with your nose, chewing slowly and listen with your ears as well as using your tongue to savor the texture
● Take a small bite each time and focus on your breath during chewing
● Always showing gratitude for your meals
You can also intentionally include stronger flavours by using herbs, spices, pickles or marinades (eg. mint sauce, lime, cumin etc) to help improve palatability and elevate the flavours of your food.
B. Take care of our immunity and lower the hyper-inflammatory process
+ Plant-Based Diet
As significant inflammatory responses are observed in 40-60 days post-viral infection, adoption of a plant-based diet which often results in a lower consumption of pro-inflammatory mediators may be beneficial. Plant-based diets can include a variety of vegetables, fruits, nuts, seeds and legumes which also provide dietary fiber. Gut microbiomes also use dietary fiber as a source of food. A plant-based diet also has a variety of protein-rich sources (tofu, beans, nuts and seeds) and healthy fats too (olive oil, flaxseed oil, avocado oil). Finally, phytochemicals and antioxidants included in plant foods aid in the reduction of free radicals and the reduction of inflammation. Of course, a predominantly plant-based diet does not need the entire exclusion of meat from your diet. Animal protein sources including fish, poultry, and eggs are also good suppliers of essential amino acids and iron.
According to the European Commission, micronutrients (such as Vitamin C, Vitamin D, Vitamin A, Vitamin Bs, Iron, Zinc, Selenium, and Copper) play an important role in the immune system's optimal function. We'll go through a few of them in more detail below.
+ Vitamin C
Ah, the good old Vitamin C ! Did you know that interest concerning the potential effects of Vitamin C towards respiratory virus infections traces back all the way to the 1940s ? Vitamin C will not prevent anyone from becoming infected with Covid-19, but according to a review, there is substantial evidence that it can help decrease the duration of respiratory virus infections, and its advantages are not limited to a single respiratory virus or viral group.
+ Vitamin D
Low vitamin D levels in the blood have been linked to severe or fatal Covid-19 in several investigations. In individuals with sub-optimal vitamin D status with mild to severe COVID-19 symptoms, daily oral vitamin D3 therapy for two weeks has been demonstrated to shorten the time to recovery for cough and taste sensory loss. Vitamin D3 should be used as an adjuvant treatment for COVID-19 patients with low vitamin D levels, even if just for a short time. On the other hand, 5–30 minutes of sun exposure to the face, arms, legs, or back without sunscreen at least twice a week between 10 a.m. and 3 p.m. has been proposed to create Vitamin D.
+ Vitamin E
Vitamin E is an antioxidant that aids immune function by boosting antibody synthesis, lymphocyte proliferation, and natural killer cell activity, as well as maintaining cell membrane integrity. Vitamin E also suppresses the synthesis of pro-inflammatory cytokines, which helps to control inflammation.
+ Vitamin B
Vitamin B aids in the appropriate activation of both innate and adaptive immune responses, as well as the reduction of pro-inflammatory cytokine levels, improved respiratory function, and endothelium integrity. Vitamin B has also been demonstrated to aid in energy generation, which may be beneficial for persons suffering from malnutrition or prolonged fatigue. Vitamin B is essential for the body's regular physiological functioning since it aids the body in the utilisation of nutrients such as carbohydrates, proteins, and fats.
+ Vitamin A
Vitamin A plays a unique role in the respiratory system, reducing harmful inflammation and assisting in the healing of the respiratory epithelium. Vitamin A regulates a number of genes involved in our immune system's reactions. Many studies have concluded the protective nature of Vitamin A on the effects of viruses.
+ Manuka Honey
Honey, which includes a variety of potentially beneficial compounds, has been shown in research to have special qualities that may help fight and ease the symptoms of Covid-19 infection. Honey coats the inside lining of the throat and, thanks to its antiviral, antibacterial, antioxidant, and anti-inflammatory qualities, eliminates dangerous germs while also soothing the throat.
Manuka Honey, on the other hand, has been proven in studies to have the capacity to fight lung infections caused by antimicrobial-resistant respiratory bacteria. Similarly, honey flavonoids have antiviral activity and have been shown to be effective against SARS-CoV-2. Honey (particularly manuka honey) has a strong therapeutic benefit in general.
C. Gastrointestinal Health
Because the gut contains 70% of immune cells, a healthy gut microbiota is critical for the development of a healthy immune system. Patients with long-term Covid-19 problems, on the other hand, may develop changes in their gut microbiota. Even six months after recovery, the rich intestinal microbiota of individuals infected with Covid-19 may not return to normal levels, but probiotics have been proven to restore gut homeostasis.
As an adjuvant treatment, probiotics have been proven to considerably alleviate illness symptoms, along with a reduction in inflammation and healing from gut microbiota abnormalities.
Cough, fatigue, and subjective well-being ratings improved considerably in both the early and chronic phase (Long-Covid) groups over the course of 30 days. Participants who were more likely to have gut dysbiosis at the start of the experiment (sedentary, hospitalised, older males with GI symptoms) responded to the probiotics considerably better statistically. Participants experienced a substantial improvement in GI and non-GI symptoms after this dietary intervention, as well as a significant increase in overall well-being.
Specific studies conducted on the gut microbiome of patients with post acute Covid-19 syndrome were shown to have increased numbers of Ruminococcus gnavus, Bacteroides vulgatus and lower levels of Faecalibacterium prausnitzii (F.prau). The presence of gut pathogens were correlated to occurrence of persistent respiratory symptoms, neuropsychiatric symptoms and fatigue. Butyrate is known to produce beneficial adaptations in brain plasticity and function, and butyrate-producing microorganisms such as such as R. inulinivorans and F. prausnitzii may protect the host from many negative effects of stress, including hair loss and anxiety-like behaviours.
Bifidobacterium pseudocatenulatum, F.prausnitzii, R.inluinivorans, and Roseburia hominis, which are known to boost immunological function, were shown to be decreased in those with long-Covid at 6 months. As a result of the findings, there may be a significant motivation to manage the gut flora in order to aid recovery and lessen the burden of Long-Covid.
To date, Malaysia has had a total of 4.15 million Covid-19 positive cases, how many of those who survived are going through Long Covid? With public health measures and strategies established by the government, the impact of Covid-19 on people has been decreasing as indicated by a lower number of hospitalizations, ICU admissions and mortality rate. However as the world continues to grapple with the pandemic and the after effects of it, whereby Long-Covid, a significant post-viral complication that is being more and more commonly reported in patients, there is a need to highlight the need for nutritional education and support for individuals that are experiencing lingering symptoms in order to best optimize recovery post Covid-19 infection.
Kimberly Ling S.A, Dietitian
BSc (Hons) in Dietetics with Nutrition
International Medical University
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