You’ve probably heard breakfast is the most important meal of the day. That’s backed up by research. But should it also be the most substantial meal of the day? It depends.

When Should Breakfast Not Be the Biggest Meal of the Day?

If breakfast means the first meal of the day – as technically the word means to ‘break the fast,’ then there are a few instances in which it should not be the biggest.

For some people, the only time they can squeeze in exercise is first thing in the morning. But they need food to fuel a workout. If your breakfast doubles as a pre-workout meal it shouldn’t be the biggest. Exercising on a full stomach can cause discomfort, from feeling sluggish to having cramps. (Hold off on your workout for a least two hours after a substantial meal.)

To fuel a moderate to intense morning workout, eat a simple snack. The snack should be fairly quick-digesting, with carbohydrates and some protein (less than 10 grams) and maybe a little fat. If you’re trying to get more protein into your day, this snack is the first opportunity to get a few grams of protein.

Here are some pre-workout snacks to eat 45 minutes to one hour before working out:

• Banana with peanut butter
• Fruit with a hard-boiled egg or a small container of yogurt
• Café latte (with protein-rich dairy milk or soy beverage) with collagen
• Small smoothie
• One or two fruit-nut butter protein balls
• Half of a protein bar

Another time it does not make sense for the first meal of the day to be the biggest one is if you have zero appetite in the morning. Many people struggle to eat after waking up, but if your brain is making decisions, it needs nutrients (not just coffee).

“Not eating within the first 30 to 45 minutes of waking can increase the stress hormone cortisol. It may also increase cravings later in the day, like the body is trying to make up for the food it missed first thing in the morning,” explains Leah Kleinschrodt, MS, RD, LD Dietitian at Nutritional Weight & Wellness.

Eating soon after you wake up helps cortisol levels make their natural decline, leaving you less stressed and ready to take on the day.

For those who don’t feel like eating much first thing in the morning, any of the pre-workout snacks above are good choices. Wagner also suggests drinking part of a packaged protein shake or high-protein chocolate milk, then finishing the rest of the beverage later in the morning when you make time for a bigger breakfast.

When Should Breakfast Be the Biggest Meal of the Day?

Breakfast should probably be the biggest meal of the day most of the time.

Eat a big breakfast:

• After your morning workout as a post-workout meal
• If you don’t do morning workouts, try to eat within 45 minutes to one hour of waking
• If you’re not hungry right after waking or don’t have time, eat a small snack, then eat a big breakfast mid-morning when you have more time

The research that supports eating a big breakfast is stacking up. There are benefits for satiety. In one study, people who ate a protein-rich breakfast (25 to 30 grams) were less hungry throughout the day.

Higher amounts of protein in a post-workout breakfast especially after resistance training can help with building muscle. Some researchers have suggested that especially for women, higher amounts of protein (around 30 grams) can be helpful; as this amount of high-quality protein contains enough of the amino acid leucine to stimulate muscle synthesis.

Eating a substantial breakfast can affect your energy levels for the whole rest of the day. In emerging research, scientists found a connection between eating breakfast and having more energy for physical activity and endurance exercise later in the day.

Breakfast should almost certainly be bigger than the nighttime meal. A big dinner before bed can lead to stomach discomfort. Spacing the eating of protein evenly throughout the day may lead to better weight management, instead of having one large meal at night.

If it works best for your schedule to have a bigger lunch – along with a substantial breakfast, the point is that it’s a good idea to space protein foods throughout the day.

What Should Be in a Big Breakfast?

What exactly does a ‘big breakfast’ mean? Does it mean a tall stack of pancakes? Not exactly – those should be saved for special occasions.

A breakfast should contain all the macros: protein, fiber-rich carbohydrates and some healthy fats.

Researchers have found that increasing dietary protein above current recommendations may lead to better body weight management. And breakfasts with 25 to 30 grams of protein may help with satiety.

These breakfasts all contain fiber-containing carbohydrates, some fat and about 25 to 30 grams of protein:

• 2 eggs in pasta sauce with bell peppers over 1 cup quinoa
• 3-egg white scramble with mushrooms, 1 slice whole-grain toast, 1 cup milk
• 3-ounce low-sodium deli beef on whole-grain bread, tomatoes, pickles
• 1 cup Greek plain yogurt with fruit and 1 ounce peanuts
• 1 scoop whey protein powder in a green (spinach, banana, milk) smoothie
• Egg, cheese, Canadian bacon on whole-grain English muffin
• 2 tablespoons peanut butter on 2 slices whole-grain toast, chocolate soy milk
• Higher-fiber, real-fruit protein bar (like RX Bars) with 1/2-cup of cottage cheese

Bottom Line: If it works best for your schedule to have a bigger breakfast – along with a substantial lunch, that’s a good idea. Make sure your breakfast, or at least a healthy snack, happens shortly after waking. Then take time for a substantial breakfast including fiber-rich carbohydrates, a hefty amount of protein and usually some blood-sugar-stabilizing healthy fats.

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