One of the most disruptive things to glucose homeostasis can be travel.
Fundamentally this can be boiled down to the fact that glucose is controlled by the endocrine system and this is a relatively slow adaptive system, with the nervous system functioning more for quicker adaptation. Disruptions such as timezone shifts, loss of sleep and changes to diet can all impact glucose metabolism.
Let’s look at some of the key factors that play a role and how to mitigate some of their impact.
The importance of sleep is undeniable and this extends to glucose control. As discussed in this blog, lack of sleep or disrupted sleep can significantly impact glucose metabolism. This means that the same foods will have a more significant impact on glucose levels, what may normally not cause much change can increase glucose quite significantly in the context of poor sleep.
Sleep is often impacted when flying for obvious reasons. The non-obvious reason that can cause sleep disruption is a lack of physical activity. Sufficient physical activity is important for good quality sleep.
There is significant scientific evidence suggesting that a critical amount of sleep is needed to benefit metabolic outcomes. It should be noted though, that sleep is not sedation and thus the use of some sleeping medications and substances like alcohol does not necessarily aid restorative sleep, despite them perhaps aiding in one falling asleep.
Whilst related to sleep, this itself is slightly different. Some of the impacts of disturbed circadian rhythms were covered in the above-linked blog article, but this fundamentally boils down to the misalignment of eating times to body clock. The body’s ability to digest food will be different and this may play a role in some of the bloating many people experience whilst traveling.
Both insulin and glucose sensitivity vary across a day, and this misalignment can be a big driver in impaired glucose control whilst traveling.
Interestingly, one of the more significant zeitgebers (environmental signals that align circadian rhythms) is actually food. So this relationship is somewhat bidirectional.
Highly Processed Foods
Many new Supersapiens are surprised to realize that glucose control is not just about sugar and other carbohydrates. There is a significant role of food processing in the glycemic impact of foods. The more processed a food is, usually the more of an impact it will have on glucose, even if it’s not particularly high in carbohydrates. A good example of this is something like Oat milk which is often the cause of a significant glucose rush.
When traveling, especially by plane, food options are usually quite processed unfortunately and this can be a major factor in poor glucose control.
Most users and non-users alike would know that activity positively impacts glucose control. More activity generally means more stable glucose. This poses a glucose stability challenge when it comes to travel as, unfortunately, a lot of travel is about sitting and being sedentary.
This often dovetails into other factors above too; eating processed foods and disrupted sleep for example.
Additionally, in people without diabetes, sedentary behavior has been independently linked to increased risk of abnormal glucose metabolism, including increased insulin secretion and decreased insulin sensitivity. Exercise is known to increase insulin sensitivity over time as well as support better glucose regulation.
So How Do You Mitigate the Negative Impacts of Travel on Glucose?
First and foremost do your best to adjust time zones as quickly as possible, and prioritize getting enough sleep.
Try to get as much movement as possible during travel and maybe even bump up exercise in the days leading into your travel. During travel, getting up periodically and using the ‘Soleus Pushup’ are two great ways to help.
Do your best to order your macronutrients as discussed here, potentially also bringing along healthier snacks such as nuts which will help from a glucose standpoint given their protein, fat and fiber content. Some people also find fasting helps, specifically with bloating and timezone shifts.
Finally, don’t forget to hydrate! Travel, especially air travel can dehydrate you and given glucose is a concentration, glucose will naturally be higher when there is less volume of fluid.
- Hamilton MT, Hamilton DG, Zderic TW. A potent physiological method to magnify and sustain soleus oxidative metabolism improves glucose and lipid regulation. iScience. 2022 Aug 5;25(9):104869. doi: 10.1016/j.isci.2022.104869. PMID: 36034224; PMCID: PMC9404652.