Calorie Restriction Reduces Sympathetic Nervous System Similar to Beta Blockers
What if you walked into a high pressure work situation without a pounding heart or sweaty palms? What if you were about to give a talk to a room full of 5,000 people, all eyes on you, without feeling nervous? What if your kids never got on your last nerve, because you’re completely in control?
A recent study found that calorie restriction, which is a practice of reducing calories without malnourishment, could reduce the “fight or flight” stress response as well as prescription medication.
Stress is a part of life, especially these days. Your response to stress is what makes all the difference. While a racing heart and a shaky voice might be part of big events, sometimes, people experience these types of physical reactions to everyday events.
The sympathetic nervous system and the fight or flight response
As humans, we have a built-in stress response so that we can outrun danger, fight off predators – to save ourselves from actual threats. When a stressor is present, your body releases stress hormones that elevate your heart rate, release glucose (sugar) into your bloodstream for energy, and tense your muscles, among other things. You may have heard of this response referred to as the “fight or flight” response. This is controlled by the sympathetic nervous system.
At the same time, body processes that require energy and would interfere with your ability to fight or flee, like digestion and other processes.
Stress hormones are there to help us
Our stress response is a good thing. If a threat is present, we want to be on high alert and ready to do what we need to do. But when there’s no threat, we want to be able to return to a relaxed state quickly.
Situational stress vs. chronic stress
We are built for occasional stress. It’s chronic stress that causes problems. When your stress response is triggered time after time without ample time to recover, it takes a toll on your body. If you feel hot under the collar because you’re sitting in traffic, because you have a big project at work, or because your neighbor’s kids rode their bikes on your grass, your stress response might be getting the best of you. Modern life doesn’t present us with frequent serious threats.
Since stress works directly on your heart, your cardiovascular health is of particular concern when you’re under chronic stress. Heart disease is the leading killer among Americans, and frequent bursts of stress may be making your heart work harder than it should.
Beta blockers and stress
Beta blockers block stress hormones like adrenaline from reaching the heart, so that your heart rate doesn’t increase too steeply. Doctors prescribe beta blockers to patients after heart attacks or when patients have irregular heartbeats. Sometimes, beta blockers are prescribed for anxiety to prevent the fight or flight response from triggering.
That’s why the study that found that calorie restriction calms sympathetic nervous system activity similar to beta blockers is so interesting. Researchers found that not only does calorie restriction reduce the fight or flight response, but the practice also has protective effects on the heart muscle.
Keep in mind that the study was conducted on rats, and further research is necessary to determine whether the same or a similar effect would be observed in humans.
Plus, there are limits. If your calorie consumption is so low that the body thinks it’s starving, that would trigger a stress response, which would have the opposite effect.