High blood sugar weakens immune health

It was known already before COVID-19 that high blood sugar levels alter the innate immune response to infections. Previous viral pandemics showed that diabetes worsened the progress of viral infections resulting in higher mortality rates. Read here about further findings from the COVID-19 pandemic regarding the impact of high blood sugar on immune health.

Some years ago, Jafar and coworkers (2016) reported that an acute rise in blood sugar levels significantly alters the innate immune response to infections. Accordingly, previous viral pandemics showed that diabetes worsened the progress of the viral infection and resulted in a higher mortality rate. (Singh et al. 2020) For COVID-19, more and more data around the globe became available confirming that the severity of COVID-19 intensifies with elevated blood sugar levels and the death rate seems to be 2-3 fold higher in the case of patients with diabetes. However, the increased risk affects not only patients with diabetes: data from Europe and China confirm that elevated blood sugar levels are a risk factor for severe COVID-19 progress and death, independent of diabetes. (Das et al. 2020; Singh et al. 2020, Richardson et al. 2020; Meyers et al. 2020; Gude-Sampedro et al. 2020, Zhu B. et al. 2020; Zhu L. et al. 2020 ; Zhang et al. 2020; Huang et al. 2020, Carrasco-Sanchez et al. 2020)

The question that arises is, why has a high blood sugar concentration such a tremendous impact? Several factors contribute to this: a high blood sugar is associated with disorders such as obesity, which is another risk factor for a severe COVID-19 progress. In addition, high blood sugar levels impair the innate immune response and cause a state of chronic inflammation with high levels of the so-called angiotensin-converting-enzyme-2 (ACE-2). The SARS-CoV-2 virus uses ACE-2 in the lung as an entry into the body and causes an additional increase of inflammatory processes that can even result in an overreaction of the immune system, a so-called “cytokine storm”. The reduced immune response allows the virus to replicate and spread without restrictions. Moreover, negative effects of the virus have also been seen on cells in the pancreas, that secrete hormones to regulate blood sugar. ACE-2 is abundant in the pancreas where the SARS-CoV-2 virus again finds entry and can damage those cells. This bring blood sugar even more out-of-control. (Cuschieri & Grech et al. 2020; Rajpal et al. 2020)

Therefore a healthy blood sugar is not only relevant to reduce the risk for non-communicable diseases such as diabetes mellitus type 2 or cardiovascular disease. Keeping the blood sugar in a healthy range plays a crucial role for immune health as the data for COVID-19 drastically shows. Isomaltulose can help to keep the blood sugar low and stable and thereby supports overall health.


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