With a busy schedule, breakfast can easily be overlooked, but research suggests that skipping that meal may be more harmful than you think.

"As they say, breakfast is the most important meal of the day," says Dan Buettner, longevity researcher who coined the term "blue zones."

"It gives your body the energy to make it through the day and can be an opportunity to get a lot of healthy foods into your body to start the day."

DON'T MISS: Certain cereals can actually lower your energy to start the day. Reach for these breakfast foods instead

But the impacts of having breakfast in the morning trickle down to more than just your energy levels. Here are some ways that skipping breakfast can affect your overall health.

2 reasons why skipping breakfast isn't harmless

1. Not eating breakfast doesn't align with a longevity diet

In blue zones, communities with the highest life expectancies and the longest-lived people in the world, breakfast is a priority, according to Dan Buettner, which indicates that breakfast may be great for longevity.

"We have a saying, 'breakfast like a king, lunch like a prince and dinner like a pauper,'" Buettner says.

"In blue zones, they are eating the biggest meal of the day for breakfast and then eating smaller meals as the day progresses, oftentimes eating an early dinner and then not eating until breakfast the next day."

Breakfast in blue zones also looks different than the typical breakfast in the American diet, he notes.

"People should avoid most of what is marketed to us in America as breakfast foods such as pop tarts, sugar laden cereals, yogurts and granola," Buettner says. "Instead, people should take a page out of the blue zones and eat a hardy, healthy breakfast."

Aim to eat these foods in the morning to align your eating style with the world's healthiest communities:

• Beans
• Vegetables
• Rice
• Fruits
• Miso
• Oats

"I often start my day with a minestrone stew full of vegetables and beans," Buettner says. "I challenge everyone reading this to try eating minestrone stew or rice and beans as their breakfast for a week and see how they feel."

2. Skipping breakfast can negatively affect your mood and sleep quality

If you typically skip breakfast and notice your mood or sleep isn't as great as you'd like, there may be a correlation.

A 2023 study with more than 700 college students as participants found that not eating breakfast was associated with effects on sleep chronotypes and increased depressive symptoms, which negatively impacted sleep quality. Researchers note that the effects of not eating breakfast on sleep quality weren't significant, but there was a noticeable difference when compared to cases where people ate breakfast regularly.

A smaller study with 66 healthy adults in their 20's found that the frequency of breakfast consumption was associated with changes in sleep quality, mood and even eating habits. Those who ate breakfast consistently had a "better perceived sleep quality, mood upon waking, and alertness upon waking compared to those that skip breakfast," according to the study.

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