For the first time, Australian scientists have demonstrated that moderate weight loss stops many of the harmful changes that occur in the immune systems of people with obesity, especially those with Type 2 Diabetes Mellitus.
The immune system contains a wide variety of cells that act to protect us from and thwart infections caused by organisms including, bacteria, viruses, and fungi. The immune system’s cells maintain a balance that impacts our health in a positive way. Numerous lifestyle factors, can impact this delicate balance, such as obesity (too much body fat) and diet, and can alter the balance, causing the increased production of certain immune cells that can harm, rather than help our organs.
Scientists have recognized for many years that extra body fat, abdominal in particular, can cause the creations of immune cells that increase inflammation, an underlying process that contributes to numerous disease processes. Also, fat tissue activates macrophages, another inflammatory immune cell.
Australian researchers at the Garvan Institute of Medical Research, evaluated obese people with Type 2 diabetes or prediabetes (also known as Metabolic syndrome). The participants were maintained on a restricted diet between 1000 and 1600 calories a day for 6 months. Gastric banding surgery was performed 33 months into the study to further decrease food consumption.
Dr Alex Viardot and Associate Professor Katherine Samara, were the lead researchers. The results found showed an 80% reduction of pro-inflammatory T-helper cells, and smaller levels of other circulating immune cells (T cells, monocytes and neutrophils) and decreased levels of macrophages in fat tissue. Their results were published in the prestigious Journal of Clinical Endocrinology Metabolism.
Dr. Samaras noted, “Excess weight disorders now affect 50% of adult Australians, with obesity being the major cause of Type 2 diabetes and some cancers.
“The situation has reached crisis point, and people must be made aware that excess fat will affect their immune systems and therefore their survival.
“We have found that a modest weight loss of about 6 kg is enough to bring the pro- inflammatory nature of circulating immune cells back to that found in lean people.
“These inflammatory cells are involved in promoting coronary artery disease and other illnesses associated with obesity.
“This is the first time it has been shown that modest weight reduction reverses some of the very adverse inflammatory changes we see in obese people with diabetes.
“We also showed that the activation status of immune cells found in fat predicted how much weight people would lose following a calorie restricted diet and bariatric surgery. Those with more activated immune cells lost less weight.
“It’s the first time this has been described and is important because it helps us understand why some people lose weight more easily than others, and that inflammation is involved in regulating the response to bariatric surgery.”
Source: Research Australia