Exposure to social stress was associated with accelerated aging of the immune system, according to an NIA-funded study recently published in PNAS. The body’s immune system changes as people age, and there’s large variability in these changes. The study, led by researchers at UCLA, investigated whether social stressors added to immune system decline.
The researchers analyzed data from more than 5,500 people enrolled in the Health and Retirement Study, a long-term, nationally representative study of Americans over age 50. The researchers measured stress by analyzing responses to questions about exposure to various types of social stress, including discrimination, trauma, and other life events, such as unemployment. They also analyzed the participants’ immune profiles — a snapshot of immune system function — by drawing blood and measuring white blood cell levels, specifically T lymphocytes (also called T cells). T cells are an essential part of the immune system and help the body fight off infection.
Months after recovering from mild cases of COVID-19, people still have immune cells in their body pumping out antibodies against the virus that causes COVID-19, according to a study from researchers at Washington University School of Medicine in St. Louis. Such cells could persist for a lifetime, churning out antibodies all the while.
The findings, published May 24 in the journal Nature, suggest that mild cases of COVID-19 leave those infected with lasting antibody protection and that repeated bouts of illness are likely to be uncommon.
“Last fall, there were reports that antibodies wane quickly after infection with the virus that causes COVID-19, and mainstream media interpreted that to mean that immunity was not long-lived,” said senior author Ali Ellebedy, PhD, an associate professor of pathology & immunology, of medicine and of molecular microbiology. “But that’s a misinterpretation of the data. It’s normal for antibody levels to go down after acute infection, but they don’t go down to zero; they plateau. Here, we found antibody-producing cells in people 11 months after first symptoms. These cells will live and produce antibodies for the rest of people’s lives. That’s strong evidence for long-lasting immunity.”
There seems to be no limit to the promises on the Internet for foods and dietary supplements that allegedly “boost” or “support” your immune function. There’s more than a grain of scientific truth in it, and the prospect of enhancing immune function with nutrition is a busy area of research—some of it by scientists at Tufts’ Human Nutrition Research Center on Aging (HNRCA) and Friedman School of Nutrition Science and Policy.
We know that nutrient deficiencies weaken the immune system and leave people vulnerable to illness. But if your nutrient intakes are adequate, can certain foods and nutritional supplements still improve immune function?
There is no definitive answer yet to this question—although there is reason for optimism. “I would not say it’s entirely an open question,” says Simin Nikbin Meydani, PhD, senior scientist and director of the Tufts’ HNRCA Nutritional Immunology Laboratory. “We do have promising evidence from animal studies and some human clinical trials that specific nutrients might be able to help strengthen an aging immune system. But we need additional research.”
“Our data suggest vitamin D may be involved in maintaining the health of the immune system as well as the skeletal system,” said one of the study’s authors, Mary Ward, PhD, of the University of Ulster in Coleraine, U.K. “This study is the first to find a connection between vitamin D levels and inflammation in a large sample of older individuals.”
Vitamin-deficient seniors more likely to have biomarkers for heart disease, inflammation
Older individuals who are vitamin D deficient also tend to have compromised immune function, according to new research accepted for publication in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).
Vitamin D plays an important role in helping the body absorb calcium needed for healthy bones. The skin naturally produces vitamin D when it is exposed to sunlight. People also obtain smaller amounts of the vitamin through foods, such as milk fortified with vitamin D. More than 1 billion people worldwide are estimated to have deficient levels of vitamin D due to limited sunshine exposure.
“Our data suggest vitamin D may be involved in maintaining the health of the immune system as well as the skeletal system,” said one of the study’s authors, Mary Ward, PhD, of the University of Ulster in Coleraine, U.K. “This study is…