Posted by: Pamela Mason2 JUL 2014
The Western diet, which tends to be high in sugar, salt and saturated fat and low in some unsaturates, is associated with a variety of health issues from obesity and diabetes to cardiovascular disease and cancer but US researchers say that it is also a potential contributor to immune dysfunction. In their review of the literature, they point to in vitro evidence linking intake of simple sugars with reduced white blood cell phagocytosis and increased inflammatory markers in the blood while complex carbohydrates found in fruits and vegetables reduce inflammation. Preliminary evidence suggests that a high salt diet increases interleukin-7 (IL-7) mediated inflammation although how this affects humans is as yet unclear.
Strong evidence exists for an effect of saturated fat on inflammation as it feeds into pro-inflammatory prostaglandin pathways while omega-3 fatty acids are generally associated with anti-inflammatory effects. Dietary fats also alter the lipids of membranes of immune cells, potentially disrupting immune function. Saturated fats can also interact with bacterial receptors and may alter outcomes from infections. This research also found evidence that simple dietary sugars could facilitate the growth of harmful gut bacteria over beneficial ones. Most critically, our poor dietary behaviors are encoded into both our DNA and gut microbial population, and thus these harmful immune modifications are passed to our offspring during their most critical developmental window in the womb. If these impacts of diet on immune function are translatable to humans, they could provide further evidence that the inflammatory nature of many common long term conditions such as CVD is related to the modern diet.