• Gut health is a key cornerstone of our overall health as it can affect many bodily systems.
• A diet high in fiber, fermented foods, and polyphenols can help support a healthy gut microbiome.
• Emily Leeming, a gut health expert and dietitian, sees her breakfast as a chance to boost her fiber intake.

A gut health scientist and dietitian shared the two breakfasts she often eats to help boost her gut microbiome.

Gut health is a key cornerstone to overall health because it is thought to influence everything from the immune and endocrine systems to the brain, Emily Leeming, a gut microbiome researcher at King's College London and a former private chef, told Business Insider. Experts consider a gut that contains a diverse community of microbes healthy.

What's great about the gut microbiome, the name for the trillions of microbes that live in the gut lining, is that what we eat shapes it, Leeming, who is based in London and the author of "'Genius Gut: The Life-Changing Science of Eating for your Second Brain," said.

Eating a diet packed with fiber, polyphenols — the compounds that contribute to the pigment in many fruits and vegetables — and fermented foods, can help those microscopic bugs thrive, she said.

Leeming sees her first meal of the day as a key time to boost fiber by adding some veggies or fruits if she's preparing something sweet. She also tries to get around 20 to 30 grams of protein in each meal, including breakfast.

"It's those simple small changes that we make on a regular basis that actually have the most impact," Leeming said.

She combines all those elements while making her meals taste great.

"Food has to taste delicious, otherwise life is sad," she said.

Roasted veggies and eggs on rye pumpernickel toast

Leeming is a big fan of pumpernickel rye bread as it's high in fiber. "For one slice, it's around seven grams of fiber," she said.

She loves to pair it with roasted vegetables and eggs. She places them all in a small oven dish and roasts them for 15 minutes at 392 degrees Fahrenheit.

"At the moment, I've been doing zucchini and baby tomatoes," she said, adding that she mixes in harissa and crumbles feta cheese on top.

At the end, she sprinkles some mixed seeds on top for added fiber and protein.

"What's really surprising to many people is that whole grains, beans, nuts or seeds actually tend to contain much more fiber than fruits and vegetables, although of course we still need to get fruits and vegetables," she said.

Overnight oats

Overnight oats prepared in batches are another breakfast favorite, Leeming said. She uses rolled oats and adds kefir, grated carrot, apple, blueberries, cinnamon, mixed nuts, chia seeds, and flax seeds.

Leeming's oats contain lots of gut-loving ingredients. Chia seeds feature about 30 grams of fiber per 100 grams, and berries tend to be higher in fiber than other fruits because they contain seeds, she said. They're also high in polyphenols.

She opts for kefir, a fermented milk drink, instead of yogurt because it tends to contain more probiotics, the good microbes.