Ever wonder why you overeat when you’re stressed rather than under eat? While some of us do under eat (about 30%) the majority overeat (70%) (1). If you’re part of the former group, read on to see why this happens and what you can do to change it.
The Fight or Flight Response: Not Just One Response
The concept “fight or flight” is commonly known as our body’s automatic response to stress. Historically, it’s known to be triggered in response to literal attacks on our survival. Deadly animals and/or other types of deadly predators triggered a cascade of hormones in our bodies designed to strengthen us and protect our lives. Today, the same hormones are triggered in response to our modern day stressors (running late, financial constraints, inter and intrapersonal conflicts) and “chronic stress” necessary for modern day “survival” is unfortunately, the norm for many.
Research has actually identified two separate “systems” that occur within our bodies when we’re exposed to stress. While both are part of the “fight/flight response” one of the two systems tends to predominate and dictate whether we over or under eat in response to it.
Two Automatic Responses: HPA and SAM Systems
Our stressors can either activate a HPA response (hypothalamus-pituitary-adrenal system) or a SAM (sympatho-adrenomedullary) response. Read on to learn the differences between the two and how they influence your eating habits.
NOTE: While the following may be momentarily “hard to chew”, it’s worth taking the time to “digest” since ultimately, understanding what happens in your body in response to stress is the first step in learning how to manage it.
Our HPA system is our “stress responding” central control station and is located in our brain’s hypothalamus and brain stem. When facing stress, it releases corticotrophin (CRH) hormones (hormones that help release other hormones). CRH then stimulates the secretion of ACTH (a regulatory hormone) from the pituitary gland. The circulating ACTH then acts on the adrenals where it stimulates the release of cortisol. Finally, this cortisol feeds back to the brain to shut off further cortisol secretion. This loop protects us from prolonged detrimental cortisol secretion and exposure and is meant to serve as an adaptive response to stress.
photo credit: google images
A SAM activation is somewhat simpler. When stressed, the hypothalamus activates the adrenals and the adrenals then secrete the hormone adrenaline. SAM activation also stimulates the release of hormones like epinephrine and norepinephrine (related to the anti-inflammatory response). The SAM activation is also faster and has a more immediate physiological effect on the body.
How The Two Responses Effect Your Eating Behaviors
Chronic stress means that one of these two systems is constantly active. If your HPA axis is your main stress response, cortisol is the main hormone floating through your body. We’re all familiar with the detrimental effects of chronic cortisol exposure has on overall health. Elevated cortisol due to chronic HPA activation also directly affects our eating habits. Here’s how:
SAM activation: The “better” stress response
Increased heart rate and increased blood flow to muscles induced by a primary SAM activation, actually induces a decrease in digestion along with a decrease in appetite. From an evolutionary perspective this happens because bodily activities such as food intake and digestion are considered physiologically life threatening when encountering stressors. Additional characteristics of the SAM response related to hunger include:
How to change your HPA response to a SAM response
Amazingly, you can actually control your body’s automatic stress response! It all depends on how you perceive your stress. Research shows that if you perceive your stress as uncontrollable, a threat to your well-being and/or self-esteem, feel defeated or fearful, your HPA axis gets triggered. As a result, feelings of distress such as fear of failure and/or embarrassment serve as a “more potent trigger of cortisol release” (1).
On the other hand, if you view your stressor as a challenge (a demanding but controllable situation), you then activate your SAM system as your predominate response. Perceived challenges then inhibit hunger for the sake of overcoming them in addition to decreasing overeating.
Tips on Change
Paying attention to your automatic thoughts induced during stress takes effort, time and practice, but worth it in the long run.
Below are 4 ways that you can start activating your SAM response rather than continuing to use your HPA response. Keep in mind that excess of both systems can have detrimental effects on the body. However, due to our modern day, stressed induced society, “managing” stress is a more realistic and viable solution rather than removing it.
1. Pay attention to your body throughout the day.
Many times we may not even realize that were stressed. One way to identify it is to make an active effort to notice your bodily sensations. Tense muscles, hunched shoulders, tightening of the chest and clenched fists are all examples of elevated stress hormones. Making an active effort to notice this tension can then help you proceed to identify thoughts surrounding it.
2. Learn to take action.
The learned belief that situations in our lives our uncontrollable stem from a multitude of circumstances. However, actively working on first taking responsibility for what you can change, followed by action towards change will allow you to slowly start viewing stressors as challenges with solutions rather than never ending threats.
3. View problems as opportunities for growth.
Many of us fall victim to the mentality that certain stressors “just are” and that there is nothing we can do to change them. However, viewing your stressor as an opportunity for growth and/or an exercise in resiliency is an effective way to access your SAM system rather than HPA system. This induces a sense of control and mastery on a problem that would otherwise feel uncontrollable or threatening.
4. Practice plays on words.
You may not “mean” them in the beginning but actively forcing yourself to replace certain “threatening” words with more empowering ones, may help put you on the right track for change. For example, replace “I’m so stressed” with “I’m so excited.” Or, “I can’t take this” with “I got this.” You can even take it a step further and state “bring it on” for an anticipated highly stressful day. All of these mantras have been shown to ultimately activate the SAM response over the HPA response. Definitely worth practicing.
photo credit: google images
Ultimately, when it comes to stress, identifying how we respond to it, both mentally and physiologically is a must for weight control and/or management. Attempting to lose weight and/or restrict food, for many, is a cortisol inducer on its own. Identifying your predominant stress response along with actively changing your thoughts surrounding it may help you to change your hormones, your eating behaviors and your weight.
Source and Inspiration:
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