Weekend can be different from weekdays in all kinds of ways – sleeping patterns, work schedules, socializing – and new study looks at possible health effects of shifting eating habits at weekend, described as ‘eating jet lag’.
Published in Communications Medicine, study follows up on what we know about so-called social jet lag: that irregular sleep patterns, caused in part by differences in weekend routines, can be detrimental to health. Researchers from France and Spain analyzed data on 104,806 adults registered with ongoing health study, cross-referencing eating habits against cardiovascular disease CVD, over average follow-up period of 8.1 years.
While there were no clear correlations in data for women, when it came to male participants, greater variation in meal times between weekend and rest of week was associated with higher rates of heart disease – even after accounting for several other factors, including social jet lag. “Our results suggest role for meal timing regularity between weekends and weekdays in CVD etiology, independently of sleep duration and diet quality, specifically in males,” write researchers in published paper.
“If confirmed in other studies, meal timing regularity could be strategy to mitigate cardiovascular disease risk.”
How Eating Jet Lag Measured – Midpoint Between First And Last Eating
To measure eating timings, researchers found average mid-point between when participants first ate or drank something on weekday, and when they last ate or drank something. Same was then done for weekends. Bigger gap between weekday and weekend mid-points, higher CVD risk. For men, extra hour of eating jet lag was associated with 14 percent higher rate of CVD overall, and 21 percent higher rate of coronary heart disease including heart attacks specifically.
Having meals earlier at weekend was less common in study cohort, but was linked with greater risk level. “These associations are independent of diet quality and remain significant after adjustment for bedtime, total sleep time, and social jet lag,” write researchers. Data gathered here isn’t enough to prove direct cause and effect, as there may be other contributing factors that both increase CVD risk and make eating jet lag discrepancies more likely.
Further research needed to identify reasons for these associations, but study team suggests disruptions and irregularities to natural biological clocks might be putting extra stress on body – including heart.
Why No Link For Women – Hormones Metabolism Higher Baseline Risk In Men
As for lack of any associations for women, researchers point to differences in hormones and metabolism as possible explanations. CVD risk also known to be higher in men to begin with. “In many industrialized societies, irregular eating patterns, such as skipping breakfast and late-night eating, are becoming more frequent,” write researchers.
“Rest days usually Saturday and Sunday generally allow individuals to align their sleep and meal patterns more closely with their biological clock. “This inconsistency in sleep and food intake timing may disrupt circadian rhythms – internal clocks that coordinate homeostasis and metabolism and run on ∼24-hour cycle.”
We have several circadian clocks ticking away inside us, and studies repeatedly found when daily rhythms shift – whether sleeping, eating, or another habit – there can be health complications. Next steps could involve looking at more diverse groups of people, and greater range of work habits – it was assumed for this study that all participants had Saturday and Sunday as weekend – as well as testing how attempts to correct eating jet lag might improve heart health over time. “If our results are confirmed in other studies, meal timing and regularity could be important focus for interventions to reduce chronic disease risk and alleviate associated public health burdens,” write researchers.
Research published in Communications Medicine.
Q&A
Q: What is eating jet lag and how does it affect heart risk in men?
A: Eating jet lag is gap between weekday and weekend meal midpoints first to last eating; study of 104,806 adults over 8.1 years found each extra hour linked to 14% higher CVD overall and 21% higher coronary heart disease in men, independent of diet quality, bedtime, sleep time and social jet lag.
Q: Does changing meal time on weekends increase heart disease risk for women?
A: No clear correlations in data for women in this cohort; researchers point to hormone metabolism differences and higher baseline CVD risk in men as possible reasons; needs confirmation in other studies.
Q: How was eating timing regularity measured?
A: Average midpoint between first eating/drinking and last eating/drinking calculated separately for weekdays and weekends; difference between midpoints = eating jet lag; earlier weekend meals less common but linked to greater risk.
FAQ
1. How large was eating jet lag study?
104,806 adults from France and Spain in ongoing health study, average follow-up 8.1 years, cross-referencing eating habits against cardiovascular disease, published in Communications Medicine.
2. Is eating jet lag same as social jet lag?
Related but different; social jet lag is irregular sleep patterns due to weekend routines; eating jet lag focuses on meal timing shifts; associations remained significant after adjusting for social jet lag.
3. Does this prove weekend eating shift causes heart attacks?
No, observational data not enough to prove direct cause and effect; other factors may increase both CVD risk and eating jet lag; disruptions to circadian rhythms ∼24-hour internal clocks coordinating homeostasis metabolism suggested as possible mechanism.
4. Why irregular eating patterns increasing?
In industrialized societies skipping breakfast and late-night eating becoming more frequent; weekends allow aligning sleep meal patterns more closely with biological clock, creating inconsistency.
5. What are next steps for research?
Look at more diverse groups, range of work habits not just Saturday Sunday weekend assumption, and test whether correcting eating jet lag improves heart health over time.
Disclaimer: This article for informational purposes only and does not constitute medical advice.
