Adequate nutrition and hydration play an important role in the improvement and rehabilitation of patients with Covid-19[i],[ii],[iii].
My preference is to obtain nutrients from whole foods and if inadequate, to supplement. A nutritionally balanced diet comes from diversified food sources that provide adequate micronutrients for optimal health. As it turns out, ingesting 5 or more serves of fruit and vegetables can improve antibody response to the pneumococcal vaccine.[iv]
Good News! You can get a rough estimate of your nutrient intake with a paid subscription from the Cronometer app. There is also a searchable database of nutrients from food.(see Resources)
Macronutrients are the larger groups of food that we need to eat to produce energy: carbohydrates, proteins and fats.
And while we’ve heard the common phrase to ‘eat everything in moderation,’ have you heard the phrase “companion eating”?
Not surprisingly, excessive intake of highly refined carbohydrates (processed foods) can increase the risk of inflammation and adversely affect health[v],[vi]. With companion eating, having white rice with vinegar (sushi), fermented pickles, dairy (100ml milk) or bean products (fermented soy beans) may reduce the glycaemic index by 20-40%[vii].The glycaemic index measures how fast the sugar spikes in the blood and we want to keep our sugar levels consistent. Keep in mind the body likes things to be in balance or in homeostasis or will fight tooth and nail to reach equilibrium, spending unnecessary energy on this while it could be working on general house-keeping. The key to conserving energy is to keep sugar levels steady by minimising excessive intake and mixing carbohydrates with some fat.
The quantity of macronutrients is crucial. Some of us will need more, others will need less as it boils down to what reserves you have and what you get up to each day. Your reserves are dependent on what you eat, your nutrient status (e.g. how your body breaks down food and absorbs it) and your body stores. Too much carbohydrates end up being stored as fat so a rough measure of whether you’re eating the right amount is your body mass index (BMI); while it is not the most accurate metric (it doesn’t take into account different ethnic groups), it gives a good indicator if you’re overweight or at the right weight. Aim for a BMI between 20-25.
Sufficient protein intake is required for building the immune system (e.g. antibodies). The Australian & New Zealand recommended protein intake is 0.84g/kg/day for men <70 years and 0.75g/kg/day for women <70 years[viii].
Why is this important? The body requires 8 amino acids and 9 different vitamins for optimal health so eat a variety of foods.
On the flipside, too much of a macronutrient is no good either.
Some of us have had our gallbladders removed and one reason could be eating too much fats that overtaxes the body. For myself, I found the BePure Macronutrient Profile Test insightful as to which macronutrient serves me best. My husband and his mother have a high carbohydrate predisposition and can eat as much carbs as they like without putting on weight while I have a mixed predisposition for protein and fats for energy production. Here’s what happened: when I cut down carbs at dinner, I lost 3-4 kg over a month. Moral of the story: each one of us is different and there is no one-size fits all diet and if you add companion eating to the mix, it highlights how we can enhance our current predispositions.
Simply stated, if you’re obese, reduce weight as excess fat can be inflammatory. High body mass index (BMI) or excess adiposity carry risk factors for complications arising from COVID-19 infection[ix].
Omega-3 oils like EPA and DHA may suppress pro-inflammatory pathways and increase pro-resolving mediators that alleviate inflammation[x]. It turns out that we don’t make these essential fatty acids so we need to consume them from our diet. The Australian upper level of intake for EPA and DHA is 3,000 mg/day. I aim to eat fish at least twice a week. One more thing, lower-mercury sources like sardines and anchovies are best.
Choline is an important ingredient for cell membranes and is the building block for acetylcholine, a neurotransmitter crucial for movement and memory[xi]. A rich source of choline are eggs. The Australian recommended adequate intake for adults is 425mg for women and 550mg for men, that is equivalent to about 4 egg yolks/day.
Keep in mind: other foods that strengthen the immune system include herbs, spices, cruciferous vegetables and mushrooms. The best part, eating a variety of nutrient-dense wholefood will provide diverse micronutrients to the body.
Here’s what you need to know: fill up on a variety of nutrient-dense food (e.g. shop in the fresh fruit and veggie section of your favourite supermarket/grocery store and limit food in packaging). Eat enough protein to feel full. Buy the best quality you can afford and:
Eat seafood at least twice a week
Eat 2-3 eggs daily, ideally poached to boost choline intake
Include different types of salts to diversify mineral intake (I mix local salt with Celtic salt etc)
Herbs are full of antioxidants so use them generously
Eat mushrooms regularly, they can strengthen the immune system
Stimulate the phase 2 detoxification pathway with broccoli sprouts
Practise mindful eating: chew 32x per bite if you have 32 teeth!
[i] Fernández-Quintela A, Milton-Laskibar I, Trepiana J, Gómez-Zorita S, Kajarabille N, Léniz A, González M, Portillo MP. Key Aspects in Nutritional Management of COVID-19 Patients. Journal of Clinical Medicine. 2020; https://doi.org/10.3390/jcm908 , 9(8):2589
[ii] Ali Gorji, Maryam Khaleghi Ghadiri, Potential roles of micronutrient deficiency and immune system dysfunction in the coronavirus disease 2019 (COVID-19) pandemic. Nutrition 2021(82)https://doi.org/10.1016/j.nut.2020.111047
[iii] Calder PC, Carr AC, Gombart AF, Eggersdorfer M. Optimal Nutritional Status for a Well-Functioning Immune System Is an Important Factor to Protect against Viral Infections. Nutrients. 2020; https://doi.org/10.3390/nu12041181 , 12(4):1181
[iv] Andrew Gibson, J David Edgar, Charlotte E Neville, Sarah ECM Gilchrist, Michelle C McKinley, Chris C Patterson, Ian S Young, Jayne V Woodside, Effect of fruit and vegetable consumption on immune function in older people: a randomized controlled trial, The American Journal of Clinical Nutrition, Volume 96, Issue 6, December 2012, Pages 1429–1436, https://doi.org/10.3945/ajcn.112.039057
[v] O’Keefe, J. H., Gheewala, N. M., & O’Keefe, J. O. (2008). Dietary strategies for improving post-prandial glucose, lipids, inflammation, and cardiovascular health. Journal of the American College of Cardiology, 51(3), 249–255. https://doi.org/10.1016/j.jacc.2007.10.016
[vi] Cooper ID, Crofts CAP, DiNicolantonio JJ, et al. Relationships between hyperinsulinaemia, magnesium, vitamin D, thrombosis and COVID-19: rationale for clinical management. Open Heart. 2020; doi:10.1136/openhrt-2020-001356, 7(2):e001356.
[vii]Sugiyama, M., Tang, A., Wakaki, Y. et al. Glycemic index of single and mixed meal foods among common Japanese foods with white rice as a reference food. Eur J Clin Nutr 57, 743–752 (2003). https://doi.org/10.1038/sj.ejcn.1601606
[viii] Australian National Health and Medical Research Council (NHMRC), Australian Government Department of Health and Ageing and the New Zealand Ministry of Health (NZ MoH).
[ix] Steenblock, C., Schwarz, P. E. H., Ludwig, B., Linkermann, A., Zimmet, P., Kulebyakin, K., Tkachuk, V. A., Markov, A. G., Lehnert, H., de Angelis, M. H., Rietzsch, H., Rodionov, R. N., Khunti, K., Hopkins, D., Birkenfeld, A. L., Boehm, B., Holt, R. I. G., Skyler, J. S., DeVries, J. H., Bornstein, S. R. (2021). COVID-19 and metabolic disease: mechanisms and clinical management. The Lancet Diabetes and Endocrinology, 9(11), 786-798. https://doi.org/10.1016/S2213-8587 (21)00244-8
[x] 2010, Calder PC. Omega-3 Fatty Acids and Inflammatory Processes. Nutrients.; https://doi.org/10.3390/nu2030355 , 2(3):355-374.
[xi] Sanders LM, Zeisel SH. Choline: Dietary Requirements and Role in Brain Development. Nutr Today. 2007; doi:10.1097/01.NT.0000286155.55343.fa, 42(4):181-186.