Harvard Study: Delaying Breakfast Linked to Increased Mortality Risk

Experts often say it while emphasizing the importance of a nutritious breakfast: Eat breakfast like a king! Why so? Because the first meal of the day replenishes glucose levels, boosting energy and alertness after an overnight fast. It also kickstarts your metabolism, improves focus and memory, helps regulate blood sugar and appetite to prevent overeating later in the day, and provides essential nutrients like vitamins, minerals, fiber, and calcium.Now, many people are aware of the fact that a nutritious breakfast contributes to better heart health and overall well-being, and encourages healthier eating habits. But did you know how important it is to consume breakfast on time?A new study is shedding light on the surprising link between meal timings and longevity, suggesting that delaying breakfast is linked with a higher risk of death, along with other health issues such as fatigue, depression, poor sleep, and oral health problems.Read on to know more.As the saying now goes: How late you eat the first meal of the day might be just as important as what’s on the plate.A major new study following nearly 3,000 adults aged 42-94 over more than 20 years, suggests that delaying breakfast is linked with a higher risk of death, along with other health issues such as fatigue, depression, poor sleep, and oral health problems.Researchers from Mass General Brigham (Harvard-affiliated) and the University of Manchester analyzed data from 2,945 UK adults aged between 42 and 94, tracking them for about 22 years, to see how changes in the timing of breakfast and dinner relate to health and mortality. Led by Dr. Hassan Dashti (Massachusetts General Hospital) in collaboration with the University of Manchester, the research added fresh evidence to the growing field of chrononutrition – the idea that the timing of meals (not just what we eat) influences health and longevity.The researchers discovered that as people grow older, meal times tend to drift later – both breakfast and dinner – and the overall eating window (time in a day during which people eat) becomes narrower. The most eye-opening result? For each extra hour breakfast was delayed, there was about an 8-11% higher risk of mortality (death from any cause) during the follow-up period.Moreover, late breakfast times were linked with other health problems. Many participants who ate late also reported poorer sleep, fatigue, depression, difficulty preparing meals, and worse oral health. Those are signs not just of bad habits but sometimes of under-recognized health issues. Genetic predisposition to “late chronotype” (natural inclination to stay up late and wake up later) was also associated with later breakfast times, suggesting some of the timing shift may be built in, or influenced by internal body clocks.This isn’t just about being an early bird and someone who chooses to stick to the clock a bit too religiously. There are several biological, lifestyle, and psychological reasons timing seems to make a difference, especially in older adults.Circadian rhythms: Our body’s internal clock regulates many functions, like sleep, digestion, hormone release, and metabolism. When you delay eating relative to waking time, you may misalign your meals with optimal metabolic windows. That could reduce how well nutrients are processed and increase stress on systems (e.g., glucose regulation).Sleep and energy: Later breakfasts often go hand-in-hand with poorer sleep, fatigue, or disrupted routines. If you wake late or sleep badly, your body may already be under strain; so eating late might be more of an ‘effect’ than a ‘cause’ in some people. Also, delayed eating may reduce total energy/nutrient intake early in the day, which can affect metabolism and overall health.Behavioral and functional implications: Older adults who have mobility issues, depression, dental problems, or fatigue may find it harder to prepare or access breakfast early, or may simply not feel hungry until later. These health challenges themselves are risk factors for mortality. Thus, breakfast time might be a marker rather than just a lever.If you want to use this insight to support better health (especially as you age), here are some simple, actionable recommendations.Eat breakfast earlier, close to when you wake up: Try to have breakfast within one to two hours after waking. If you wake at 6-7 AM, aim for breakfast by 8-9 AM rather than delaying until late morning.Maintain consistent mealtimes: Just like sleep, being regular with when you eat helps your body expect food, regulate hormones, digestion, and energy levels. A schedule like breakfast around 7-9 AM, lunch around noon, dinner before 6-8 PM can help anchor your day. Missing or delaying meals often disrupts the rhythm.Prioritize breakfast quality: What you eat matters. A protein-rich, fiber-full breakfast helps stabilize blood sugar, supports digestion, and gives staying power. Think eggs + veggies, oatmeal with nuts/fruit, yogurt with seeds, whole grain toast + protein. Skipping or having sugary breakfast items may give quick energy but less sustained benefit.Look after sleep and wake patterns: Since late chronotype, poor sleep, or delayed wake times are associated with eating late, improving sleep hygiene can help. Going to bed earlier, maintaining consistent wake-up times, and limiting exposure to screens before bed – all of these help reset internal clocks.Monitor health signs and routines: If you notice fatigue, depression, difficulty preparing meals, oral health problems, or gradually delaying meals, these may be early warning signs worth discussing with your healthcare provider. Mealtime shifts may be easier to track than many other health markers.Avoid heavy meals close to bedtime: Eating dinner too late or snacking heavily late in the evening can further skew your eating window and may compound the negative effects of a late breakfast. Light dinners, earlier evenings, and minimizing snacking can help.