What Your Sleep Tracker isn’t Telling You
While wearable sleep trackers can provide valuable insight into some of the vital signs that indicate how well you’ve slept, they don’t give you the whole story of all the health factors that can come into play to affect your body’s recovery.
Here are 3 of the most influential factors in determining sleep quality that wearable trackers miss:
Hormone Levels
3 of the key hormones that are thought to affect your body’s sensation of tiredness are adenosine, melatonin, and cortisol.
Adenosine builds up in your body throughout the day and creates what we call “sleep pressure” when levels get too high. This “pressure” lets your body know that you’ve been awake too long and that it’s time to go to sleep.
Melatonin analyzes your environment and, if it concludes that your headspace is calm enough and your room is dark enough, it will switch your body into “sleep mode.”
Cortisol is a steroid hormone that increases your alertness and heartrate, released by the adrenal glands in response to stress. This is a very important hormone, of course, especially when you’re in a situation where your “fight or flight” response is necessary. But, as you can imagine, cortisol can be very detrimental if overactive. Cortisol is supposed to back off when it’s time to rest and relax. But if this does not happen, winding down and achieving restorative sleep will be almost impossible.
To better regulate these 3 hormones, we suggest:
Avoiding caffeine later in the day, as that can inhibit adenosine production
Taking steps to ensure that your place of sleep is cool and dark, to promote melatonin release
Practicing deep breathing exercises before bed to ease your mind and lower cortisol levels
Metabolism
The timing and size of your meals relative to bedtime can play a large part in how restful your sleep is. Eating heavy meals late in the evening increases core body temperature and insulin levels, which delays the onset of your body’s “sleep mode.” This can also cause blood sugar crashes after you’ve fallen asleep, which can trigger cortisol spikes and wake you up. In addition, eating high-fat or spicy foods in particular may trigger GERD (gastroesophageal reflux disease) or indigestion.
To avoid any of these sleep inhibitors, we suggest that you finish large meals at least 2–3 hours before bed. Evening snacks (if needed) should be low-glycemic and contain complex carbs, magnesium, or tryptophan. (An example of a healthy evening snack would be a banana with almond butter.) We also suggest that you limit your alcohol consumption close to bedtime, as alcohol is known to disrupt REM and cause early awakening. You also might want to consider using a Continuous Glucose Monitor to track overnight glucose patterns and adjust meal habits based on the results.
Gut Health
Your gut microbiota influence key neurotransmitters (e.g., GABA, serotonin), which affect sleep regulation. Gut inflammation or dysbiosis may alter your melatonin production, and has been linked to insomnia and disturbed circadian rhythms.
We suggest you eat a fiber-rich, plant-diverse diet. Limit artificial sweeteners, alcohol, and ultra-processed food. It may be beneficial to take prebiotics and probiotics, as well (if tolerated). It’s also important to address gut infections, SIBO (small intestinal bacterial overgrowth), or chronic bloating with professional support.
One final note
While your hormone levels, metabolic processes, and gut health are always good to keep in mind in relation to your sleep, every body is unique, and certain stimuli or meal times that negatively impact one person may not be a problem at all for someone else. Some people may also experience “orthosomnia”—anxiety from trying too hard to optimize sleep—from all of these do’s and don’ts, which paradoxically worsens sleep quality.
So, our final suggestion is to implement the strategies covered in this blog post only in ways that work for your individual needs and comfort.
