Breakfast has for long been described as the most important meal of the day. Yet in the rush of modern life, it is often the first casualty of busy schedules. Some grab a quick snack, others skip it altogether, and many wonder: does indulging in unhealthy food early in the day make it any less damaging than eating it later?
According to Valentine Idah Lagat, a clinical nutritionist at AIC Kijabe Hospital, both the quality of your diet and when you eat matter.
“Your overall diet has the greatest impact on your health, but meal timing also influences how your body processes food,” she explains.
Research in chrononutrition, the study of how meal timing affects metabolism, shows that our bodies generally process food more efficiently earlier in the day when insulin sensitivity is higher. However, she cautions that this does not mean unhealthy foods suddenly become healthy simply because they are eaten in the morning.
“A diet consistently high in ultra-processed foods, sugar, saturated fats and excess calories increases the risk of obesity, Type 2 diabetes and cardiovascular disease regardless of the time of day.”
Evidence suggests that consuming large, calorie-dense meals late in the evening is metabolically less favourable because the body’s metabolic rate slows, insulin sensitivity decreases and glucose tolerance worsens. This means the body becomes less efficient at handling sugar and fat, leading to higher blood sugar levels after meals and potentially greater fat storage over time.
So does when you eat matter? “Our circadian rhythm regulates many aspects of metabolism, including hormone release, digestion, insulin production and energy expenditure,” says Valentine. “During daylight hours, the body is naturally better prepared to digest and utilise nutrients. As evening approaches, insulin sensitivity decreases, and digestion slows.”
She adds that eating in line with the body’s biological clock may support better metabolic health.
The body also processes carbohydrates more efficiently in the morning than late at night. Even so, foods high in added sugars and refined carbohydrates can still trigger rapid blood sugar spikes, even when eaten at breakfast. Choosing minimally processed, fibre-rich foods instead helps maintain steady energy throughout the morning.
Valentine says a healthy, balanced breakfast should combine a high-quality protein, high-fibre carbohydrates, healthy fats, and fruits or vegetables. This could look like oats cooked with milk topped with groundnuts and fresh fruit, whole-grain bread with eggs and avocado paired with plain yoghurt with fruit and nuts added, or sweet potatoes served with boiled eggs and vegetables.
Is breakfast essential for everyone? “It is important, but it is not equally essential for everyone,” she says. “For children, adolescents, pregnant women and many adults, a nutritious breakfast supports concentration, nutrient intake and energy levels. Research also suggests that people who regularly eat balanced breakfasts tend to have healthier overall dietary patterns.
“The quality of the meal eaten for breakfast is more important than the timing itself,” she says, adding that eating breakfast depends on an individual’s routine, but generally, within one to three hours after waking up is reasonable.
What about skipping breakfast?
Some people experience increased hunger, reduced concentration or fatigue or end up overeating later in the day. Others adapt well and maintain stable energy levels.
For those practising intermittent fasting, which involves planned schedules for eating, some may even skip breakfast.
“Intermittent fasting can be an effective weight management strategy for some adults because it may reduce overall calorie intake and improve insulin sensitivity,” she explains.
However, she notes that success depends on what is eaten during the eating window.
“Skipping breakfast does not automatically lead to weight loss if unhealthy foods or excess calories are consumed later.”
Still, she cautions intermittent fasting is not for everyone. These include children, pregnant or breastfeeding women, individuals with eating disorders and some people with diabetes unless medically supervised.
“Nutrition should always be individualised rather than based on one rule,” she says.
Additionally, she advises that foods that provide large amounts of added sugar and little nutritional value should be limited in the morning.
These include sugary breakfast cereals, doughnuts, cakes, pastries, sugar-sweetened beverages, energy drinks and highly processed fast foods.
“These foods can cause rapid rises and falls in blood sugar, leaving people hungry again shortly afterwards, even before lunchtime. Starting the day with protein and fibre is more likely to support sustained energy.”
Why late-night eating can be harmful
Large meals high in fat or sugar shortly before bedtime may delay digestion, worsen acid reflux and reduce sleep quality.
“Poor sleep itself affects hormones that regulate hunger, increasing cravings for energy-dense foods the following day,” she says. “This creates a cycle that may contribute to weight gain and poor metabolic health.”
Moreover, sleep and gut health have a two-way relationship. Poor sleep can alter the composition of the gut microbiome, while an unhealthy gut may influence sleep quality through the gut-brain axis.
