Chronic vs. Acute Stressors 

We've been talking about the nuances of this topic as a team lately and I think the subject deserves a bit more attention than it currently receives. Let's first define a stressor. 

"A stressor can be defined as anything that disturbs allostatic balance, and the stress response is the body’s attempt to reestablish allostasis."

- Timothy A.Storlie PhD

Basically, we have a baseline (normal) state of existence known as homeostasis. We encounter stressors (stimuli) that challenge us and bring us away from our baseline. We then rest and recover and establish a higher baseline level of tolerance over time. The key here is that this movement is pulsatile in nature. We experience an acute stressor (stimuli), adapt, recover, and return to our baseline. Rinse and repeat. We build resilience and elevate our tolerance to stressors. This is a simple overview of our stress adaptation cycle and the key is that it involves the pulsatile introduction of ACUTE stressors. 

Many of us understand and have heard that chronic stress is bad. The famous example from Robert Sapolsky, Ph.D. references the evolutionary adaptation for us to be able to perceive and adapt to threats in the wild but he also states

"If you turn on the stress response chronically for purely psychological reasons, you increase your risk of adult-onset diabetes and high blood pressure. If you're chronically shutting down the digestive system, there's a bunch of gastrointestinal disorders you're more at risk for as well."

Get to the Point! 

Many individuals, including some extremely intelligent people, forget to ask themselves if the stressor that they are examining is chronic or acute in nature. Here are two health-related examples to help you see what I'm talking about. 

Short Term Stressors with Positive Long Term Impact on Health 

Exercise- Actually breaks down the body in the short term, elevates inflammatory markers like CRP (among others) and it is actually the recovery process that follows to repair the tissue and reduce inflammatory markers that build our baseline and provide long-term benefits. 

Nutrition- I'll provide two examples here to illustrate the same point from two perspectives.  

Plant-Based- You eat a salad full of wonderful veggies. These provide fiber among vitamins, minerals, and these fun things called phytochemicals. These phyto or (plant) chemicals provide a short-term stressor to the body that comes from the natural defense system that plants have developed through evolution. Our body's response to and recovery from this stress provides us with long-term health benefits. Example- Sulfurophane is a phytochemical from broccoli that has been shown to exhibit anti-cancer effects when consumed by humans. 

Animal-Based- You ingest a whey protein shake or eat a grass-fed steak after a training session. The proteins from this meal trigger the activation of mTOR and help promote muscle protein synthesis (or the building of new muscle) to repair the area you just worked out and "damaged". As I've written about in the past, chronic elevation of mTOR is often associated with a decrease in lifespan or longevity. However, the key point here is we are pulsing this activation in response to a training stimulus and subsequent nutrient intake to enhance recovery. 

This last point above is where many get caught up in the weeds and miss the overall view of the forest while staring at a single tree. These examples both exhibit a short-term (acute) stressor via exercise and nutrition that helps support recovery, establish a higher tolerance to stress in the future, and promote health over the long term. 

Key Takeaway

When evaluating a health habit, challenge yourself to look at the big picture and not just the current action.