According to a report on Nature, obesity correlates with a dulled immune response to Covid-19. And vaccines for a handful of other conditions often don't work as well in obese people, suggesting that a shot for Covid-19 might not provide as much protection as researchers would like.
"The severity of Covid-19 is potentially high in obese or diabetic people. The fact is that the immunity and the process of healing may be slower in an obese person than a healthy person," Navneet Sood, Pulmonary Consultant, Dharamshila Narayana Superspeciality Hospital, told IANS.
"Such conditions also influence the immune system's response to vaccines. Same is applied on Covid-19 vaccine. But there is no study yet which strongly confirms the direct relation between Covid-19 vaccines' effectiveness and obesity," Sood added.
Obesity can cause chronic, low-grade inflammation, which is thought to contribute to the increased risk of conditions such as diabetes and heart disease. As a result, people who are obese might have higher levels of a variety of immune-regulating proteins, including cytokines.
The immune responses unleashed by cytokines can damage healthy tissue in some cases of severe Covid-19, according to the report.
According to a recently released study, published in the journal Perspectives on Psychological Science, suggests that depression, stress, loneliness and poor health behaviours can weaken the body's immune system and lower the effectiveness of new Covid-19 vaccines.
The researchers emphasise that environmental factors, as well as an individual's genetics and physical and mental health can weaken the body's immune system, slowing the response to a vaccine.
"In addition to the physical toll of COVID-19, the pandemic has an equally troubling mental health component, causing anxiety and depression, among many other related problems. Emotional stressors like these can affect a person's immune system, impairing their ability to ward off infections," said the researcher of the study Annelise Madison from the Ohio State University in the US.
Health experts also suggest that there are several factors that may lower the effectiveness of new Covid-19 vaccines and therefore it should be avoided.
"Immune system of people with severe health conditions and low immunity may influence the response to the vaccine," said Jyoti Mutta, Senior Consultant, Microbiology, Sri Balaji Action Medical Institute, New Delhi.
"People on steroids, severe liver diseases, uncontrolled diabetes or with immunosuppressed conditions like cancer patients, severe kidney patients may come in this category. Also alcohol consumption should be avoided. If one is leading a healthy lifestyle there is no apparent contra indication," Mutta added.