Many people eat breakfast around 7 a.m. on weekdays but push the meal back on weekends after sleeping in. Some delay breakfast by several hours or settle for a late brunch, repeating a different eating pattern every weekend. This gap between weekday and weekend meal times is known as meal timing jetlag. A shift in one or two meals may seem trivial, but recent research suggests such gaps may be linked to a higher risk of cardiovascular disease.
A research team including France's National Research Institute for Agriculture, Food and Environment (INRAE) and the National Institute of Health and Medical Research (Inserm) tracked 104,806 adults for eight years to examine how gaps in weekday and weekend meal times affect cardiovascular disease. For men, every additional hour of meal timing jetlag was associated with a 14% higher risk of cardiovascular disease and a 21% higher risk of coronary artery disease. Men whose weekend meals came an average of two hours earlier than on weekdays had a 68% higher risk of coronary artery disease than men who ate at consistent times. Among women, by contrast, the risk did not rise significantly. The link between meal timing gaps and cardiovascular risk was pronounced only in men. The researchers suggested that physiological differences between the sexes, lifestyles, work environments and circadian rhythms may have combined to produce the result.
Another point worth noting is that changes in daily rhythms, including meal times, do not affect only cardiovascular health. Blood circulation, closely tied to the cardiovascular system, is also closely linked to the health of the spine and joints. The discs between the vertebrae contain almost no blood vessels and depend on nutrients seeping from microvessels around the vertebrae. Because the discs sit at the very end of the nutrient supply chain, poor blood flow can easily worsen disc health.
In one study published by Finnish researchers, atherosclerosis of the abdominal aorta and narrowing of the arteries leading to the lumbar spine were associated with disc degeneration and low back pain. This suggests that as circulation and vascular health deteriorate, the burden on the spine and the rest of the musculoskeletal system can grow. Domestic research has produced similar findings. According to a paper published by the Jaseng Spine and Joint Research Institute in the SCI(E)-indexed international journal PLOS ONE, among more than 17,000 adults aged 20 and over who took part in the Korea National Health and Nutrition Examination Survey, those who had lived with high blood pressure for more than 10 years had roughly 1.42 times the prevalence of low back pain and osteoarthritis compared with those diagnosed three years earlier or less.
The relationship between blood pressure and pain also deserves attention. In the same study, people with high blood pressure were about 20% less likely to report low back pain than those with normal blood pressure. The researchers suggested the finding may stem from the relationship between hypertension and pain sensitivity. Still, feeling less pain does not necessarily mean the musculoskeletal system is in good condition. People with elevated blood pressure should therefore not ignore recurring minor pain or discomfort in the lower back and elsewhere in the musculoskeletal system, and should visit a medical institution to identify the exact cause.
Shifting a meal slightly later or earlier is often dismissed as trivial. But the body is affected more by repeated patterns of daily life than by a single change. If a wide gap between weekday and weekend meal times becomes a habit, biological rhythms can be thrown off, affecting blood pressure and blood sugar as well as musculoskeletal health. Remember that health begins not with extraordinary effort but with habits repeated every day.
