October 29, 2025 : In recent years, there has been a surge of interest in intermittent fasting and time-restricted eating as methods for weight control and metabolic health. Yet a growing body of research now suggests that skipping breakfast — particularly when done haphazardly or as an “unstructured” fast — may carry significant health risks. According to a recent review and several cohort studies, habitually missing the first meal of the day is associated with elevated risk of metabolic dysfunction, cardiovascular disease, and even certain cancers.
What the Research Shows
A meta-analysis published in Circulation and Vascular Biology found that people who skipped breakfast had about a 21% higher risk of experiencing a cardiovascular event, and a 32% higher risk of all‐cause mortality compared with regular breakfast eaters.
In another large U.S. cohort following over 6,500 adults for 17 to 23 years, researchers found that those who “never” ate breakfast had a hazard ratio (HR) of 1.87 for cardiovascular mortality compared to daily breakfast eaters — even after adjusting for diet, BMI and other risk factors.
Futhermore, a Chinese cohort study revealed that adults who skipped breakfast or ate it very infrequently had a significantly higher risk of gastrointestinal cancers — including oesophageal, liver, gallbladder and colorectal cancers — than those who ate breakfast regularly.
On the metabolic front, one review of observational studies indicated that compared to breakfast eaters, breakfast‐skippers had:
- 10% higher risk of metabolic syndrome
- 17% higher risk of abdominal obesity
- 21% higher risk of high blood pressure
- 13% higher risk of disturbed blood lipids
- 26% higher risk of elevated blood sugar
These findings suggest that skipping breakfast may disrupt metabolic regulation, insulin sensitivity and other key physiological systems.
Why Might Skipping Breakfast Be Harmful?
Researchers have proposed several mechanisms explaining why missing breakfast could harm long-term health. First, prolonged fasting between dinner and the next meal may disrupt circadian rhythms and insulin sensitivity, making the body less efficient at managing blood sugar and lipid metabolism.
Second, people who skip breakfast tend to have erratic eating patterns later in the day, may consume more calories in fewer meals, choose less healthy snacks, and experience higher peaks in blood sugar and insulin.
Third, elevated cortisol and sympathetic nervous system activity have been noted in those skipping breakfast, which may raise blood pressure, increase arterial plaque and heighten cardiovascular risk.
Fourth, the gastrointestinal implications — in the case of breakfast skipping and cancer risk — may involve increased secretion of gastric acid and digestive juices without food to act upon, leading to chronic irritation and inflammation of the gut lining.
Though causality cannot be definitively proven from all studies (many are observational), the associations are robust enough to warrant concern.
Intermittent Fasting vs. Skipping Breakfast
It is important to distinguish between structured intermittent fasting (IF) and unplanned or habitual breakfast skipping. The recent review noted that the increased risk was more clearly linked to unstructured skipping of breakfast, rather than planned eating-window regimens.
IF methods that include a defined eating window, adequate nutrient intake, and good overall lifestyle may have different outcomes than simply skipping breakfast due to time pressure, low appetite, or habit. Experts caution that skipping breakfast without a plan can undermine metabolic health.
Who Is At Risk?
While the habit of skipping breakfast may affect many, certain groups are particularly vulnerable:
- People with existing metabolic risks (pre-diabetes, high blood pressure, fatty liver disease) where skipping breakfast adds additional strain. For example, a study found that in individuals with metabolic dysfunction‐associated fatty liver disease (MAFLD), skipping breakfast raised cardiovascular mortality risk by nearly 2.85 times.
- Younger adults with irregular schedules, shift workers, those with high stress and late meals.
- People whose overall diet and lifestyle are already compromised (poor sleep, low physical activity, frequent late-night eating).
For these groups, the incremental risk may be higher.
What Should One Do?
Based on present evidence, nutrition and health experts suggest the following:
- Aim to include a balanced breakfast most days. A combination of protein (eggs, yogurt, pulses), whole grains, fruits/vegetables and healthy fats is recommended.
- If one chooses to practise intermittent fasting, make sure it is structured, with clear eating windows, nutrient adequacy and consistency built in — rather than just skipping breakfast out of convenience.
- Avoid letting the gap between dinner and the next meal become excessively long and unplanned.
- Monitor other lifestyle factors carefully: maintain healthy sleep, regular physical activity, maintain a reasonable weight and manage stress.
- If you already have metabolic issues (diabetes, hypertension, fatty liver), discuss with your healthcare provider before skipping breakfast regularly.
Limitations & What We Still Don’t Know
While the associations are strong, there are caveats: many studies rely on self‐reported breakfast habits, have potential confounding (skipping breakfast may be a marker of other unhealthy behaviours) and cannot fully establish causation.
Further research is needed to explore the impact of how one skips breakfast, the quality of breakfast, the timing of meals, and how intermittent fasting protocols may be differentiated from casual skipping.
Nevertheless, the accumulating evidence suggests that breakfast should not be dismissed as insignificant — especially for long‐term health.
Final Take
Skipping breakfast may seem like a minor lifestyle choice — perhaps saving time or aligning with a fasting trend — but mounting research indicates it could increase risk of high blood pressure, impaired metabolism, cardiovascular disease, even certain cancers, and may contribute to long‐term damage. While more study is needed, making breakfast a regular, nutrient-rich habit appears to be a simple move with potentially meaningful benefits for metabolic and cardiovascular health.
Summary
Habitually skipping breakfast, especially without a structured plan, is linked to higher risk of metabolic syndrome, cardiovascular disease, and some cancers — making that morning meal more important than many realise.