Skipping Breakfast for Weight Loss: Get the Facts

Skipping breakfast

“Breakfast is the most important meal of the day.”  If you want to lose weight, the general opinion is that you should eat breakfast in the morning. This is supposed to boost your metabolism. But is that really true? And will you gain weight if you skip breakfast? Or is it better to skip breakfast for weight loss? We decided to take a closer look at what the research says to answer your questions. 

Is Breakfast Important: Frequently Asked Questions

1. Does breakfast jumpstart your metabolism?

Your body uses energy for everything you do, including eating. Energy is needed to store food in your stomach, transport it to your small intestine, absorb it (into the bloodstream) and digest it. In technical terms, this is known as “diet-induced thermogenesis.” This, together with your basal metabolic rate and physical activity, determines your daily calorie intake. When you burn more calories than you consume, you lose weight.

So, does breakfast jumpstart your metabolism? Studies on this topic are inconclusive. It is still unclear whether this diet-induced thermogenesis after breakfast stimulates your metabolism, making you burn more calories.(1

2. Do I consume more calories if I skip breakfast?

One study looked at the connection between breakfast and calorie consumption among children between the ages of two and 12 years old in the US.(2) Children who skipped breakfast consumed fewer calories per day, but the rest of the snacks and meals throughout the day were larger. 40% of their daily calories were covered by snacks high in sugar, fat, and salt. The children who ate something in the morning ate more fruit, whole grain products, and low-sugar dairy products throughout the day. This could indicate that people who eat breakfast every day generally lead a healthier lifestyle.  

Research on adults barely showed any difference in weight and BMI, no matter whether they ate breakfast or not.(3) It appears to depend on how healthy and balanced your diet is for the rest of the day and how active you are.

3. Am I less hungry during the day when I don’t eat in the morning?

When you eat something in the morning, you find yourself getting hungry again at lunchtime, and you feel like you could eat a huge meal. But if you skip breakfast, you don’t really feel hungry even hours later… Does this sound familiar? The fact is that your body gets used to a routine. The stomach is an elastic organ. When it’s empty, its volume is about 50 ml. When you eat, it can expand up to two liters. If you regularly eat large portions, your stomach gets used to a lot of content. This means that you will feel hungry faster when it remains empty for a longer period of time. Plus, eating breakfast stimulates your metabolism. If you eat the last meal of the day in the evening and then skip breakfast, your stomach content is relatively small. As a result, you don’t get hungry. But this doesn’t mean that you will automatically gain weight if you for once eat more than usual.

Did you know?

The hormone ghrelin is responsible for your hunger in the morning. It is also known as the “hunger hormone.” It regulates your feelings of hunger and fullness. Studies have shown that ghrelin levels in your blood are particularly high in the morning.


You should keep the following in mind:

  • Not all breakfasts are created equal. There is a big difference between eating sugary chocolate muesli or oatmeal with low-fat yogurt and fresh fruit.
  • If you skip one of the main meals of the day, you may not get all the macro and micronutrients (carbohydrates, protein, fat, vitamins, etc.) that your body needs.
  • Eating a meal in the morning can have a positive effect on your blood sugar concentration. Plus, breakfast should help reduce postprandial hyperglycemia (higher blood sugar levels after eating) in people with diabetes mellitus. Opt for meals high in protein, high-quality fats, and fiber. 
  • Running on an empty stomach can be a welcome change in your training. Especially when your goal is to lose weight.
    Do you want to improve your performance, build muscle or run faster? In that case, it is a good idea to fill your energy reserves before working out, so you can give it all you’ve got.

So, should you skip breakfast for weight loss?

The answer is yes and no. Many reasons speak for and against it. No matter whether you decide to eat breakfast or not: the main thing is that you listen to your body and keep your personal goal in mind. If your stomach is already growling as you climb out of bed, you should give your body the energy it needs. But don’t force yourself to eat when you don’t feel like it. Eat when you are hungry, and put your fork down when you start to feel full.


Julia Denner Julia is a dietician and sports nutritionist. Before she began her position as Communications Specialist at Runtastic, she spent several years working as a dietician in the surgical department at Vienna General Hospital. Julia is passionate about inspiring others to eat a healthy, balanced diet. View all posts by Julia Denner