Is breakfast really the most important meal of the day? • Stronger by Science

You’ve probably heard *literally every possible claim* about breakfast. From the nostalgic “eat your breakfast so that you have energy” at home when you were a kid, to fitness influencers telling you that breakfast is the most important meal of the day or the worst thing you can do for your body.  

With the rise of intermittent fasting, one meal a day, and the constant need for short-form content, there are still a ton of conflicting claims around breakfast and whether it’s #GOATED or #VAULTED (showing my age here). 

But does breakfast actually improve training performance or body composition? A recent narrative review examined this topic specifically. Before we examine the authors’ findings, I would like to note that a narrative review is essentially a peer-reviewed blog post and sits relatively low on the hierarchy of scientific evidence, as the authors can include any studies they like and omit those they don’t. That said, assuming we do our due diligence, narrative reviews can still provide us with a sense of the literature surrounding a topic. 

But I digress. The authors found that when sessions are long (>60 minutes), pre-exercise feeding can help. That’s mostly true for morning workouts and even for some evening workouts after breakfast has been skipped, where usually small performance increases are observed. That said, there’s evidence that placebo breakfasts, containing no actual calories or carbohydrates, can improve endurance performance relative to water-only conditions in sub-60-minute cycling efforts. However, a placebo breakfast does not appear to have the same effect for longer-duration exercise. 

When looking at acute resistance training outcomes, similarly to previous research on training fasted versus fed, lifting fasted in the morning can result in fewer reps on the first one or two sets but without having much of an effect on subsequent sets. Interestingly, and similarly to endurance training, there’s also evidence that a placebo breakfast can mitigate some of those effects, hinting at the potential psychological effects that breakfast may have, especially given its perceived importance in many cultures. As far as long-term outcomes are concerned, breakfast doesn’t seem to be a game-changing variable for gaining strength or muscle, provided protein and calories are adequate and training is done in a fed state. It’s essential to note that training in a fasted state has been shown to lead to greater strength gains, but muscle growth outcomes remain largely unaffected. 

The one area where skipping breakfast does somewhat matter is in managing bodyweight in free-living conditions. The authors noted that people tend to eat less overall when they skip breakfast. However, that’s very likely a result of people consuming fewer calories, rather than some magical mechanism behind skipping breakfast. Additionally, previous research examining the effect of consuming the majority of one’s calories earlier or later in the day has found no significant difference in body composition outcomes, with the slight caveat that late eating may lead to greater hunger. It’s possible that in free-living conditions, having a big breakfast may be a way for some people to manage their hunger and therefore eat less throughout the day, but as long as you’re monitoring your energy intake, it’s unlikely to make a big difference. 

So where does this all leave us? Although breakfast doesn’t seem to be anything that you need to overthink, it’s worth considering its place within your daily diet. For some, having a balanced breakfast can be a great way to tick a few nutrition boxes early in the day (eg: fiber, protein), go about their daily tasks, and not have to worry much about planning their meals throughout the day. For others, skipping breakfast and leaving more space for a family dinner later in the day may be a more sensible approach. As far as your training and precious gains go, making sure that you’re not hungry while training still seems like a solid, and relatively simple, educated bet, regardless of whether you skip breakfast or not.