Should you kick-start your day with breakfast, or hold off and save your appetite for lunch? The debate over the first meal of the day has been around for decades. Many people grew up hearing slogans like “Go to work on an egg.” What few realise is that the phrase originated as a marketing campaign launched by the UK Egg Marketing Board in the 1950s. It was designed to boost egg sales rather than promote a scientifically proven health benefit. Nevertheless, the campaign helped cement the belief that breakfast is essential for a productive and healthy start to the day.
Over time, similar claims, including the popular saying that breakfast is the “most important meal of the day,” have become deeply ingrained in popular culture. But is there any truth behind them? More importantly, what actually happens to your body when you skip breakfast? Can missing your morning meal help with weight loss, or could it have unintended consequences for your health? Science is revealing a more nuanced picture than many people realise.
Is it OK to skip breakfast?
These days, skipping breakfast has become increasingly common. With intermittent fasting gaining popularity, many people are choosing to miss their morning meal in an effort to lose weight. In fact, a survey found that 13 percent of adults never eat breakfast. On the other hand, many people consider breakfast an essential part of their day. The growing popularity of shakes, smoothies, and toppings such as nuts and seeds for yogurt bowls and overnight oats highlights just how large the breakfast market has become.
Some specialist dietitians believe that eating a meal at some point in the morning is beneficial, although the exact timing is largely a matter of personal preference. After all, breakfast literally means “breaking the fast.” Rather than focusing on when the meal is eaten, what it consists of may be more important. While some people prefer to have a later, more substantial breakfast, others like to eat soon after waking up.
What happens when you skip breakfast?
For some people, skipping breakfast is hardly a concern. They may not feel hungry early in the morning, and avoiding the meal can make it easier to get ready and leave the house quickly. However, for those accustomed to starting the day with food and a cup of tea or coffee, going without breakfast can feel unusual. Beyond being part of a morning routine, the body may also be accustomed to receiving an early source of energy, meaning that skipping the meal could leave some people feeling hungry, weak or light-headed.
Inside the body, however, more complex processes are taking place. Intermittent fasting can alter hormone levels, including reducing insulin levels and improving insulin sensitivity. These changes can support weight management and may lower the risk of diabetes. However, research has also linked skipping breakfast and eating meals later in the day to changes in hormones that regulate appetite. One study found that these habits reduced levels of leptin, a hormone that helps signal fullness, while increasing ghrelin, often referred to as the hunger hormone.
Skipping breakfast may also increase levels of cortisol, the body’s primary stress hormone. In addition, several studies have associated the practice with significantly higher levels of “bad” LDL cholesterol. Some research has also found that people who regularly skip breakfast may face a higher risk of cardiovascular disease, although the effects can vary from person to person.
For some individuals, going without breakfast can also result in reduced energy and difficulty concentrating, sometimes described as brain fog. This may occur because the body has less readily available glucose to fuel the brain and other functions. During the overnight fasting period, the body relies on glycogen stored mainly in the liver and muscles to maintain energy levels. By morning, these stores may have been significantly reduced, prompting the body to draw on other energy sources. This process can be less efficient for meeting immediate energy demands.
The brain, in particular, relies heavily on a steady supply of carbohydrates to maintain optimal functioning, which is one reason some people may notice reduced concentration or mental alertness when they go without food in the morning.
Is skipping breakfast good for weight loss?
The answer may depend on which studies you consider, but research suggests that skipping breakfast can indeed be associated with some weight loss. A recent scientific review found that people who skipped breakfast lost an average of 0.66 kg more than those who ate it. Other studies, meanwhile, indicate that breakfast eaters consume about 260 more calories per day than those who skip the meal.
However, skipping breakfast may have other effects beyond calorie intake. It can potentially affect metabolism and alter the gut microbiome—the complex community of microorganisms living in the intestines. Missing breakfast does not necessarily mean you will consume fewer calories throughout the day. Nor does it guarantee that your remaining meals will be balanced or provide all the nutrients your body needs. In some cases, increased hunger can lead to snacking or overeating later in the day.
Rather than following trends, a more practical approach may be to eat according to your body’s hunger signals—paying attention to when you feel hungry and eating at a time that suits you. So, while skipping breakfast may be increasingly popular, there are still several reasons to keep breakfast as part of your daily routine if it works well for you.
