LIFESTYLE NEWS - Just the act of eating a meal places a large degree of physiological stress on the immune system.
Only until relatively recently in human evolution have we eaten three meals plus snacks every day.
Breakfast simply didn’t exist for large parts of history. The Romans, for example, didn’t eat it – usually consuming only one meal around midday – breakfast was actively frowned upon.
Regular working hours following the industrial revolution brought structure to mealtimes to sustain labourers. And by the late 18th century the pattern of eating three meals a day in towns and cities emerged.
But these days, people are eating more frequently than they ever have before – and often outside of meal times.
New smartphone app data shows that we now have erratic eating patterns. Many of us are continually snacking rather than eating at defined times – which means we spend up to 16 hours a day in a “fed” state.
The issue with inflammation
Your body has two metabolically different states: fasted (without food) and post-fed. The absorptive post-fed state is a metabolically active time for your body.
But is also a time of immune system activity. When we eat, we do not just take in nutrients – we also trigger our immune system to produce a transient inflammatory response.
Inflammation is a normal response of the body to infection and injury, which provides protection against stressors. This means that just the act of eating each meal imparts a degree of physiological stress on the immune system. And so for people snacking around the clock, their bodies can often end up in a near constant inflammatory state.
For around four hours after each meal, gut microbes and their components leak into our bloodstream – silently triggering inflammation by the immune system. This process is driven largely by the activation of a critical immune sensor of nutrients called the “inflammasome”, which releases an inflammatory molecule known as “interleukin-1β”.
Inflammation is only ever meant to be a short-term protective assault by our immune system. But inflammation after eating – known as “postprandial inflammation” can be exacerbated by our modern lifestyles. This includes calorie dense meals, frequent eating, excessive fructose and fatty foods – particularly saturated fat.