Night Shift Meals Create Eating Jet Lag

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Night shift doesn't only disrupt your sleep, it can completely change when you actually eat. Now, a meal at six in the evening before your first night shift, dinner at two in the morning the next night, breakfast at seven in the morning when you're finished, then it's back to normal daytime meals on your days off. Now, researchers have a name for this constant change, and it's called eating jet load. And a new study involving more than 100,000 people suggests that it may be associated with a higher risk of cardiovascular disease. Does this answer why we as shift workers suffer so badly with cardiovascular disease? So, what does this mean for someone who actually is working nights? It doesn't have to be this way. Whether you're a shift worker, trying to feel better, or a leader responsible for the people who keep your organisation running around the clock, you're in the right place.

Working With Your Biology

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Welcome to a healthy shift. I'm Roger Sutherland, and after more than four decades of working 24-7 shifts with Victoria Plus, followed by years of studying nutrition, circadian biology, human performance, and working with literally thousands of shift workers, I've made it my mission to change the conversation around shift work. Because healthier people create stronger teams, and stronger teams build better organizations. And it all starts by understanding how to work with your biology and not against it. Let's get into today's episode. And welcome back to another episode of A Healthy Shift. I, I gotta tell you, I'm absolutely thrilled that you are here and joining me in today's episodes. Not a long one today, but we have some new research. And today I want to talk about a term that you may not have actually heard before. But if you work shifts, I can almost guarantee that you are living with it. Eating jet lag.

What Eating Jet Lag Looks Like

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That's right. Not social jet lag. Not jet lag jet lag. Eating jet lag. Most of us understand the idea of social jet lag. Do you or do you not? Because that is the difference between the timing of your sleep on work days and the timing of your sleep on your days off. So let's have a look at a normal nine to fiver. You might get up at five in the morning for work every day, every single day of the week, Monday to Friday. But then you sleep in until nine o'clock on your days off. Your body is continually being pulled between the schedule demanded by work and the schedule that it would naturally prefer. Now keep this in mind. We have a circadian clock that's running all the time. And one of the things that I want people to really understand is one of the main reasons why you feel so awful and dreadful doing shift work is because what happens is you are actually sabotaging that alignment and how important it is. Now, eating jet lag is similar to that, but instead of looking at when you sleep, it's actually looking at when you eat. And we're learning more and more about this. It is the difference between the timing of your eating window on your work days and then the timing of the window on your days off. And for shift workers, that difference can be absolutely enormous. Even different shifts. So imagine that you're working a series of night shifts for argument's sake. You wake at four in the afternoon and you have your first meal shortly afterwards. You eat your last meal or snack at four o'clock in the morning. Then you finish your run of nights and return to a daytime routine. So now your first meal might be at eight in the morning, and your last meal might be at eight in the evening. You may be eating the similar foods and consuming a similar number of calories. But the timing of those calories has been moved by several hours, and that is actually eating jet lag. Now

Why Timing Changes Metabolism

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this matters because food does a lot more than simply provide energy. The timing of food also provides information to your body. Keep that in mind. Very important for you to understand. While light is the strongest signal for the central circadian clock in your brain, food timing literally helps to regulate the clocks found throughout the rest of the body, including the liver, the pancreas, the digestive system, and a cardiovascular system. Now, these are often called peripheral clocks. And this means that your brain may be receiving one signal from the light around you, while the digestive and metabolic systems are receiving another signal from your food. Now, do you understand that? It's really important that you do. Your eyes are seeing the light, but digesting food at different times creates a conflicting signal. Your brain sees darkness and it expects biological night. It's shut down, it's resting. But then a large meal arrives at two o'clock in the morning and the digestive system is suddenly being asked to process a large amount of food. Now, this doesn't mean that food becomes poisonous at night or that every meal eaten during night shift is harming you. But it does mean that your body's response to food changes across the biological day and night. We are generally better equipped to process food during the biological daytime. Insulin sensitivity, glucose tolerance, digestive function, and so many of our metabolic processes are following circadian rhythms. And when we eat at inconsistent times, particularly when the eating extends through the night or through the biological night, we may create another layer of circadian disruption.

The 2026 Cardiovascular Study

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Now, the reason for this topic is so important right now is that a new study was published on the 1st of September 2026 in the Journal of Communications Medicine. Now, the researchers examined information from 104, almost 105,000 adults who were part of the French Utre Net Sante study. Now I've linked the complete study in the show notes if you would like to read it. The average age of the participants was approximately 43, and 79% were female. Participants completed a detailed 24-hour dietary record. They recorded everything that they ate and drank, as well as the timing of each eating occasion. Now the researchers then calculated what they called an eating midpoint. Now, this is the halfway point between the person's first and last calorie intake of the day. They calculated that midpoint for weekdays, and then they redid this again for weekends. Now the difference between the two became the person's level of eating jet lag. So you think about it. Then you get to the weekend and you change your eating patterns because we go out for brunch later, we have a later lunch, we do whatever. Or we just skip meals and then we eat at wrong times, we're snacking. And this causes eating jet lag. Now the researchers followed these participants for a median of just over eight years. Not eight days, not eight weeks, or eight months, but eight years. And during that period, there were nearly two and a half thousand cardiovascular events, including coronary heart disease and cerebrovascular events such as a stroke. Now, among the male participants, each additional hour of eating jet lag was associated with a 14% high risk of cardiovascular disease and a 21% high risk of coronary heart disease. Remember, each additional hour. So that midpoint, and then how far away was the midpoint on the weekends? Now I want you to think about this as a shift worker. Keep that in mind. We'll get to it. An association was seen whether meal timing moved earlier or later on the weekend. What do you think? This is interesting because it suggests the inconsistency itself may matter not only whether someone eats earlier or later. Now there was no significant association was found among the women in this study. But that does not prove that a regular meal timing is safe for women or that women are somehow protected from eating jet lag. The researchers discussed several possible biological and lifestyle explanations for the different results. But the statistical interaction between sex and eating jet lag was not significant. Now more research is always needed before we can confidently say that the effect is genuinely different between men and women. And there are several other limitations that we also need to understand.

What The Study Can Not Prove

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This was an observational study. Now it can show an association, but it cannot prove that eating jet lag caused the cardiovascular events. And it's important that we understand this. Causation, correlation, very important. Just because these cardiovascular events occurred during the eight years of the research doesn't mean it was caused by that. The researchers adjusted their analysis for many other factors. And what they did was they considered physical activity, smoking, alcohol, body mass index, energy intake, the quality of the person's diet, how long do people sleep for, and the usual meal timing. But no observational study can account perfectly for every part of someone's life. Now, another major limitation for us is that it was not a study of shift workers, sadly. Again, the researchers did not know the participants' actual work rosters. They assumed that Monday to Friday represented work days, and Saturday and Sunday represented days off. Now that assumption will be correct for many of the people in this study, but it obviously does not reflect the working week of a nurse, paramedic, police officer, firefighter, factory worker, flight attendants, or cabin staff, or anyone else working on a normal rotating roster. In fact, the researchers ran one analysis that excluded people whose eating patterns suggested that they may have been night workers. So I'm not going to take those percentages and tell you that for every hour difference in a shift worker's meal timing raises their heart disease risk by 12%, sorry, by 14 to 21%. Because the study doesn't prove that. But what it does tell us is that greater changes in meal timing are associated with a high cardiovascular risk in a large group of people, and particularly in men. Now, it gives us another reason to investigate meal timing in actual shift workers. How good would that be? And we already have controlled laboratory research pointing in the same general direction.

Lab Evidence For Daytime Eating

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Now, in 2025, a study published in Nature Communications examined whether daytime meeting could reduce some of the cardiovascular changes caused by simulated night work. I've linked this study in the show notes as well. Now, this was a very small but a very tightly controlled laboratory trial. Twenty healthy young adults who were not shift workers were placed into a simulated night work protocol. Nineteen included in the final analysis. Now one group consumed meals during both day and night, which is common. This is what shift workers do. And the other group worked through the simulated night, but kept their food intake within the biological day. Now, importantly, the researchers controlled the amount and type of food. The main difference was when the food was eaten. Now, in the group eating across both day and night, that simulated night work produced changes in heart rate variability and a blood marker involved in the formation and breakdown of blood clots. Now, those changes were not found in the daytime eating group. The daytime eating invention also affected blood pressure, although these were short-term measurements taken under controlled laboratory conditions. Now, this does not prove that avoiding food overnight will prevent heart disease. It was a small study and it was involving young, healthy people who were not actual shift workers. Again, it measured cardiovascular risk factors, not heart attacks, or long-term disease. But unlike the larger observational study, this was a randomized and controlled experiment. So when we place these two studies together, we have one large study showing an association between inconsistent meal timing and cardiovascular disease, and one small controlled trial that meal timing can change the body's cardiovascular response to stimulated night work. And neither study gives us the final answer. But together, they strengthen the argument that when we eat deserves more attention. Because for years, shift workers have been told what to eat. Shift workers are gaining weight. It's got to be diet. And this is literally where I started with my research and my study. I wanted to study nutrition because I was told if you're gaining weight, it comes down to the law of thermodynamics. Calories in, calories out, you're gaining weight. But it's so different. Take a salad, eat more vegetables, avoid takeaway, reduce sugar, prepare your meals. Now that advice could be useful, but it actually ignores the situation that the worker is facing. You can take a balanced and nutritious meal to work and still be eating at a time when your body is not well prepared to process it. Keep that in mind. You gym junkies that take your containers to work, gotta get more calories in, and you're eating them at two o'clock in the morning. Your body's not primed to process them then. You're not metabolizing and storing them the same. It doesn't come down to just the equal calories in, calories out. It gets confusing. So this is why I teach shift work and nutrition is not only about what you eat, but it's literally about when you eat as well. But what we do with this information in the real world really matters.

Realistic Strategies Without Starving

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I'm not going to tell every night worker they must go through an entire 12-hour shift without eating. That's ludicrous. Because what that does is it actually sets people up that when they get home, they have an episode of overeating, which creates bigger problems. Now, a lot of people don't eat overnight. I need people to understand that. They don't. Naturally, they just don't eat overnight. They don't want to, they feel awful, so they don't eat. And they do it really well. A lot of people think, oh no, I have to eat. But if they didn't, they would be a lot better off. But I'm not telling you to starve yourself so that when you get home and the sun's come up and you think, good, I can eat again now. You open the pantry and you clean it out. And then you work in the fridge and you clean it out as well. That is counterproductive. Now, not eating overnight may work for some people, but it may not be appropriate or achievable for everyone. Some people burn a lot of energy at their job and they need food. For argument's sake, what about someone who's pregnant? What about someone who's managing diabetes, taking medication with food, living with an eating disorder, or working in a physically demanding role? They may all have different needs. See, everyone's different. This is why I work one-to-one with people. Fatigue and safety also matter. If not eating leaves you feeling lightheaded, distracted, or unable to work safely, that is not an effective strategy. Now, the goal around this is not perfection. As shift workers, it's not perfection. We can't work to perfection. The first

Four Steps To Stabilise Meal Timing

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practical step is simply to become aware of what your current pattern is and try and stabilize it and stick to it. For several workdays and days off, write down the time of your first calories and the time of your last calories. Remember that calories include the milk and sugar in coffee, energy drinks, soft drinks, and the small snacks that people often forget. Then it compared your workdays with your days off. Write down what you ate and the time that you ate it. And then get to your day off and write down what you ate and the time that you ate it as well. And let's have a look at how far your eating window is moving, because that eating is actually shuffling your whole circadian rhythm as well. It's sending confusing signals. So are you eating across the entire 24-hour day when you transition between nights and day off? Or are you eating a full meal before your shift, grazing through the night, eating again on the drive home, and then having breakfast before bed? That is not a lack of discipline. Night shift changes hunger opportunity, routine, and decision making. Now, many workplaces also make highly processed snack foods available overnight while providing few useful alternatives. Hello vending machines. But until you can see your pattern, you can't make a deliberate change to it. Knowledge is power here. Start writing it down. Do it for two weeks and just have a look and see how inconsistent you are. Because this is where weight gain comes from. The second step is to create one or two meal timing anchors. Now, this is where I start with clients. Meal timing anchors. Have your breakfast at breakfast time, lunch at lunch time, dinner at dinner time every day. I don't care what shift you're on or where you're at, whether it's a day on, afternoon shift, whatever. Just have that breakfast, lunch, and dinner at those normal times. An anchor is the plan point your day that stays reasonably consistent. Now, for a night worker, that might mean having a proper meal after waking and another meal before starting work or early in the shift. This places more of your food intake closer to the daytime or in the early evening, instead of leaving your largest meal until two or three in the morning. If you do need to eat overnight, let's plan it out. A lighter option. So eat well before the shift, but go lighter overnight. A lighter option which contains protein, fibre, something slower digesting, maybe low GI carbs, nuts, things like that. They're likely to be more useful than relying on your sweets, your pastries, your chips, chocolates, or damn Jenny and that cake. Or even worse, driving through and getting takeaway in the middle of the night during the circadian low. The important change is moving away from continuous unplanned grazing across the entire night. Every single biscuit in the tea room, every sugar containing coffee, and every handful of lollies extends the eating window and creates another metabolic event. Now you may not remember all of them as food, but your body does and it still has to process them. And the third step is to think about what happens at the end of the shift. So if you're going home and heading directly to bed, a large meal may make sleep and digestion more difficult. If you are genuinely hungry, a small planned meal may be appropriate. But eating a large breakfast simply because it's breakfast time can add another meal to an already extended eating window. Your body doesn't know that the cafe is serving breakfast. It only knows that it has been awake, it's working, and it's receiving food throughout the biological night. And the fourth step is to reduce the size of the swing between the work days and days off wherever you can. This doesn't mean keeping a complete night shift eating schedule when you're off work. That would be unrealistic for most people and it could interfere with the family and social life. But it means to start looking and start analyzing the unnecessary extremes. Could your final meal have occurred a little earlier? Could you keep one meal at a similar time across both schedules? Could you avoid turning the first day off into a day of almost continuous eating because you've eaten after shift, slept briefly, you're fatigued, your hunger hormones are all over the place, you've woken up for another meal, and then you've eaten again with the family again that night. Even a partial reduction in that movement may create a more predictable signal for your body. And organizations need to understand their role in this. We cannot keep treating fatigue and shift worker

How Leaders Can Support Better Eating

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health as entirely the workers' responsibility. Roster design determines when people sleep. Break schedules determine when they can eat. Workplace food options influence what they eat. And workload determines whether they get a break at all. If the only food available overnight comes from a vending machine or workers are forced to eat a large meal whenever operational demand briefly allows it, telling them to make better choices is actually off target and this is the problem. Meal timing should be part of the fatigue risk management and shift work education and should not be left a chance. So, what is the takeaway from today? Eating jet lag is the change in the timing of your eating window between your work days or a regular schedule and your days off. A large new observational study has linked greater eating jet lag with a higher risk of cardiovascular and coronary heart disease among men. And a separate controlled laboratory study found that keeping meals within the daytime prevented several adverse cardiovascular changes seen when people ate across both day and night during simulated night work. Now we do not yet have enough evidence to prescribe one perfect eating schedule for every shift worker. But we do have enough evidence to stop pretending that timing does not matter. So the hint is to start by recording when your eating begins and ends across your day and across a fortnight roster, a two-week roster, or even over a month. And have a look at the inconsistencies because those inconsistencies are all causing problems. Build your larger meals around the daytime and earlier part of the evening where possible. Reduce the unplanned eating through the biological night and aim for more consistency between working days and days off without making your life impossible. Your roster may force you to work against your biological clock, but with some planning, it does not have to control every part of when you eat as well. Now both studies are discussed, both studies discussed in this episode are linked in the show notes. So you can read the research for yourself. If this episode has helped you to understand something that you experienced on night shift, do me a favor. Can

Share It And Keep Talking

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you share it with a colleague? Bring it the attention to other people. Because these conversations really matter. Shift workers deserve more than generic advice, written for people who are working nine to five. You've been listening to A Healthy Shift. I'm Roger Sutherland, Night Shift and Sleep Specialist. Thank you so much for listening, and I'll talk to you again in the next episode. If today's episode resonated with you, don't let the conversation stop here. Share it with a colleague, a manager, a friend, a leader, or someone who has the opportunity to improve the lives of people working in a 24-7 environment. Because real change starts with awareness. And awareness changes conversations, and conversations change organizations. And organizations change lives. So thank you for spending this time with me. And until next time, I want you to remember this. It doesn't have to be this way. Take care of yourself and take care of each other.