Gut Health for Diabetic People During the COVID-19 Pandemic

 Written by: Hamza Alvi, SLU Dietetic Intern

The unwanted effects of COVID

Nowadays, it feels impossible to live our lives without a mention of COVID-19, the contagious disease caused by the virus – SARS-CoV-2. This microscopic virus has crept into every corner of our lives and has infected our bodies, our communities, our relationships, and our lifestyles. But, SARS-CoV-2 does not pose the same threat for everyone equally. The elderly is placed at a disadvantage from COVID-19 outcomes, especially if they present with underlying chronic diseases such as diabetes, lung disease, cardiovascular disease, and cancer. [1]. Majority of the people infected with COVID-19 display mild flu-like symptoms or don’t develop symptoms at all, while others rapidly degenerate with viral pneumonia. The novel coronavirus can result deleterious effects for seniors (65+ years old), including higher rates of hospitalizations, increased ICU admissions, and deaths [2]. On April 21, 2021, AARP reported 32.1% deaths seen in people aged 65 and up. Comparatively, only 0.5% deaths were seen in a person aged below 24 [3].

While the disease has contributed with unwanted consequences in the senior population, it also developed undeniable challenges for the diabetics. Type 2 diabetes acts as a prime comorbid factor of COVID-19. According to The Centers for Disease Prevention and Infections (CDC), preliminary data enabled the scientists and physicians to postulate diabetes to be the most prevailing medical condition existing in COVID-19 patients [4]. Poor glycemic control may be a potential reasoning for this finding which leads to higher mortality rate from COVID-19 [5]. Hence, glycemic management is essential for diabetic patients and a plant-rich diet — high in fermentable fibers (soluble and insoluble), pasture-raised animal proteins, and low in sugars — can help improve glycemic control and help strengthen the immune system among patients with type 2 diabetes [6,7].

Using nutrition to strengthen our immune system

Concentrating on lifestyle factors, such as dietary regimen, can enable an individual to modulate their immune system. The immune system is home to trillions of microbes- bacteria, fungi, and viruses – which inhabit inside the human body called the gut microbiome. Most of these microbes reside in our lower digestive tract and some in the colon. The human body is remarkable at metabolizing proteins, carbohydrates, and fats to its constituents, but can’t digest fiber due to the absence of enzymes that degrade fiber. Fiber travels through the digestive tract unaltered until it arrives to the colon. As alluded earlier, the gut microbiota is home to trillions of symbionts – good or bad bacteria that exists in symbiosis with us. We could generate space for pathogenic bacteria through an inflammatory diet (i.e., SAD – standard American diet) and they direct us to the path of disease. On the contrary, we can choose to consume a diet – full of fermentable fibers (insoluble & soluble) – and beneficial bacteria help us by fermenting it and producing short-chain fatty acids (SCFAs). SCFAs are generated during the fermentation of the fiber, which play as the main source of energy for enterocytes (gut cells) and keep our gut happy and healthy. SCFAs – produced as a by-product of the bacterial feast – can enter the blood circulation and can exert advantageous effects on the immune system [8] and alleviate inflammation in the gut and other organs [9]. 

The effects of fiber on our body

So, what happens to our health in the absence of fiber? typical western diet – high in processed foods, meats, sugar, and low in fermentable fibers (soluble & insoluble) – can decimate the beneficial microbial communities in the gut microbiota. Numerous studies have verified the fiber intake for many average Americans is half of the amount recommended by the American Dietetic Association (25g for women and 38 grams for men) [10]. Contrasted with other countries with high-fiber diets, such as Ghana and Jamaica, the microbiome of many Americans is less diverse in microbial communities and may be posed a higher susceptibility to disproportions in advantageous vs. pathogenic bacteria [11]. This toxic environment triggered in the gut by the consumption of processed foods and lack of fiber — a trademark of the western diet — is a breeding ground for pathogenic microbes, which carry the potential to initiate various forms of inflammatory diseases such as obesity, colorectal cancer, autoimmune disorders, and type 2 diabetes [12]. 

Say yes to plants

The positive news is that it is practical to increase your fiber intake throughout the day. It starts with simple changes, like eating an apple and a cup of oatmeal with almonds for breakfast, or adding legumes (e.g., beans, lentils, etc.) or quinoa to a salad for lunch. Since plants (e.g., vegetables, nuts, and fruits) present with distinct types of fibers resulting in unique health benefits, and some microbes may selectively prefer one type of fiber over another, consuming an assorted diet with various fruits and vegetables is the cornerstone for enhancing the health span of the gut and improving diabetes-related complications. Few of the primary tactics in increasing fiber in your diet include the following: consume a nutritious and diverse diet with a wide range of different plant-based foods, across all six food groups – fruits, vegetables, wholegrains, legumes (beans & lentils), nuts and seeds. Strive to get as many different types as you can. Canned, frozen, fresh, it all counts. Eating the rainbow allows us to flourish heterogeneous microbial communities in our gut. If we eat well, the microbes eat well, therefore, we are more likely to feel well.

References

1.      How Coronavirus Affects Older   Adults. health.usnews.com/conditions/articles/how-  coronavirus-affects-older-adults.

2.      CDC COVID-19 Response Team. “Severe Outcomes Among Patients with      Coronavirus Disease 2019 (COVID-19) – United States, February 12-March 16,      2020.” MMWR. Morbidity and mortality weekly report vol. 69,12 343-346. 27        Mar. 2020, doi:10.15585/mmwr.mm6912e2

3.      Nania, R. (n.d.). 95 percent of Americans killed by Covid were 50+. AARP.    Retrieved September 13, 2021, from https://www.aarp.org/health/conditions-       treatments/info-2020/coronavirus-deaths-older-adults.html.

4.      Preliminary Estimates of the Prevalence of Selected Underlying Health            Conditions Among Patients with Coronavirus Disease 2019 — United States,          February 12–March 28, 2020. MMWR Morb Mortal Wkly Rep 2020;69:382–386.       DOI: http://dx.doi.org/10.15585/mmwr.mm6913e2

5.      Zhu, Lihua, et al. Association of Blood Glucose Control and Outcomes in         Patients with COVID-19 and Pre-Existing Type 2 Diabetes. 1 May       2020, www.sciencedirect.com/science/article/pii/S1550413120302382?ca      sa_token=Z62_Kb0zrqQAAAAA%3AYoK9OnCK2T3rHDULwhCYmLA4uF      8PZGoCFbzYpK4qcYYC7ZQ_JhUvDT-OU_YzFNCjBJVnNT_SihvQ.

6.      Mcintosh, et al. “Diet Containing Food Rich in Soluble and Insoluble Fiber     Improves Glycemic Control and Reduces Hyperlipidemia among Patients with         Type 2 Diabetes Mellitus.” OUP Academic, Oxford University Press, 1 Feb.       2001, academic.oup.com/nutritionreviews/article/59/2/52/1826089.

7.      Yokoyama, Yoko et al. “Vegetarian diets and glycemic control in diabetes: a   systematic review and meta-analysis.” Cardiovascular diagnosis and         therapyvol. 4,5 (2014): 373-82. doi:10.3978/j.issn.2223-3652.2014.10.04

8.      Arnolds, Kathleen L, and Catherine A Lozupone. “Striking a Balance with Help from             our Little Friends – How the Gut Microbiota Contributes to Immune           Homeostasis.” The Yale journal of biology and medicine vol. 89,3 389-395. 30   Sep. 2016

9.      Sivaprakasam S, Prasad PD, Singh N. Benefits of short-chain fatty acids and their       receptors in inflammation and carcinogenesis. Pharmacol Ther. 2016;164:144‐        151. doi:10.1016/j.pharmthera.2016.04.007

10.  UCSF Health. “Increasing Fiber Intake.” Ucsfhealth.org, UCSF Health, 31 Oct.       2019, http://www.ucsfhealth.org/education/increasing-fiber-intake.

11.  Yatsunenko, Tanya et al. “Human gut microbiome viewed across age and       geography.” Nature vol. 486,7402 222-7. 9 May. 2012,        doi:10.1038/nature11053

12.  Graham, Catherine et al. “Obesity and the gastrointestinal microbiota: a review of       associations and mechanisms.” Nutrition reviews vol. 73,6 (2015): 376-85.   doi:10.1093/nutrit/nuv00413.Wen, Li, and Andrew Duffy. “Factors Influencing       the Gut Microbiota, Inflammation, and Type 2 Diabetes.” The Journal of             nutritionvol. 147,7 (2017): 1468S-1475S. doi:10.3945/jn.116.240754