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What Is Actually Good for Your Gut?

Certain foods and supplements are marketed to help improve your gut microbiome. But what is that, exactly, and do they work?


spinner image illustration of hand magnifying the gut
Getty Images

Living inside your digestive tract is a “microbiome” of beneficial bacteria, fungi and viruses that are in constant interaction with us and also with each other, and play an important role in our health, says Ali Rezaie, M.D., medical director of the GI Motility Program at Cedars-Sinai in Los Angeles. 

While there’s no single mix that defines a healthy microbiome, in general, the more diverse it is, the more resilient it gets, Rezaie says. Consuming lots of vegetables, fruits, nuts, proteins, grains and carbohydrates helps maintain a balanced gut microbiome, but it can still get out of whack. That’s why there are so many products today that claim to be the answer to your belly issues. 

But which ones are worthwhile? Here’s what we know:

Yogurt and kefir

Good, as long as you’re not lactose intolerant. Look for kefirs and yogurts containing live, active cultures such as bifidobacteria and lactobacillus, which have been shown to boost gut health and lessen symptoms of irritable bowel syndrome (IBS).

What to look for: Avoid products with additives like emulsifiers (soy lecithin, carrageenan), which can decrease the diversity of healthy gut bacteria. Choose options with little to no added sugar, which can negate the beneficial effects.

Fiber supplements

Good. If you already get 22 grams of fiber daily (for women; 28 grams for men), there’s no need for a supplement. But most of us struggle to get enough fiber through food, in which case supplements can help. 

What to look for: It’s better to get fiber from foods (vegetables, whole grains, fruits, nuts, legumes). Talk with your doctor before starting supplementation, and avoid supplements with artificial sweeteners, sugar or other additives.

Sauerkraut and kimchi

Excellent. Fermented foods, such as sauerkraut and kimchi, increase the diversity of your microbiome and decrease inflammatory proteins linked to conditions that include rheumatoid arthritis and type 2 diabetes.

What to look for: Shop for products that are labeled as lacto-fermented and unpasteurized, and kept in the refrigerator section. Examine the jar first: You should be able to see bubbles in the liquid, which is a sign the food is fermented.

Video: How to Ferment Foods at Home
See below for these recipes from chef Erica Wides.

Kombucha

Questionable. There’s little research showing this sweet tea is good for your gut. And most kombucha comes with enough added sugar to negatively impact any gut-friendly probiotic benefits of the drink.

What to look for: Sugar is necessary for the fermentation process, but seek out the brand with the lowest amount, says Megan Hilbert, a registered dietitian nutritionist in Madison, Wisconsin, who specializes in gut health.

Probiotic supplements

Questionable. Probiotic supplements are not regulated by the Food and Drug Administration, meaning a product may not contain what’s listed on the label, Rezaie says.

What to look for: Ask your doctor whether probiotics make sense for you, and for a recommendation for a reputable brand that’s had its contents verified by a third party.

Recipes: Fermenting Foods

Kimchi

Prep time: 20 minutes

Fermenting time: 1 week

  • 2 tablespoons kosher or sea salt
  • 4 cups water
  • ¼ large napa cabbage
  • ½ medium daikon radish, peeled
  • ½ carrot, peeled
  • 1 scallion
  • 1 thumb-sized piece of ginger, peeled and minced
  • 2 cloves garlic, peeled and smashed
  • ½ onion, peeled and chopped into thick chunks
  • 1–2 teaspoons gochugaru
  • 1 teaspoon sugar

Equipment

  • Canning jar with lid
  • Fermenting lid

Instructions

  • Make a brine by mixing the water and salt.
  • Add the napa cabbage, and allow it to soak for 30 minutes.
  • While the cabbage is soaking, cut the daikon, carrot and scallion into 1-inch pieces and set aside.
  • Remove the cabbage from the brine, and allow it to drain. Save brine.
  • Blend the onion, garlic, ginger, gochugaru and sugar with a blender, food processor or immersion blender to create a paste. Add 1 to 2 tablespoons of the leftover brine if the paste is too thick.
  • Cut the cabbage into 2-inch-long pieces.
  • Add the cabbage, carrot and scallion to a bowl, and pour the paste onto the vegetables.
  • Using your hands, massage the paste into the vegetables, making sure each piece is coated.
  • Using your hands, pack the kimchi tightly into a clean canning jar, removing air from the jar and releasing the cabbage’s juices.
  • Place a fermentation lid on the jar, and store it on your kitchen counter for about a week. Once the kimchi smells sour and acidic, you can replace the fermentation lid with a canning lid and store the jar in your refrigerator.

Classic Garlic Cucumbers

Prep time: 15 minutes

Fermentation time: 4 days+

Ingredients

  • 3 tablespoons kosher or sea salt
  • 1 quart hot water
  • Kirby or pickling cucumbers, enough to fill your jar
  • 1 tablespoon pickling spice
  • 2–3 cloves garlic, peeled

Equipment

  • Canning jar with lid
  • Fermentation lid

Instructions

  • Create a brine by mixing the salt with 1 cup of the hot water, allowing salt to dissolve.
  • Once the salt is dissolved, add the remaining water and allow to cool to room temperature.
  • Fill a canning jar with cucumbers. Add pickling spice and garlic cloves to the jar. Fill the jar with brine, ensuring that the cucumbers are fully immersed.
  • Add a fermentation lid. Store the jar on your counter for a few days or up to a few weeks, until the pickles are to your liking.

Pickled Red Onions and Radishes

Prep time: 15 minutes

Fermentation time: 4 days+

Ingredients

  • 3 tablespoons salt
  • 1 quart hot water
  • 1 red onion, peeled and cut into thick slices
  • 4 radishes, roots removed, and cut in half
  • ½ teaspoon cumin seeds
  • ½ teaspoon coriander
  • 1–3 dried chiles (optional)

Equipment

  • Canning jar with lid
  • Fermentation lid

Instructions

  • Create a brine by mixing the salt with 1 cup of the hot water, allowing salt to dissolve.
  • Once the salt is dissolved, add remaining water and allow to cool to room temperature.
  • Add the onion and radishes to a canning jar in layers.
  • Add the coriander, cumin and chiles to the jar before pouring brine over the vegetables.
  • Add a fermentation lid. Store the jar on your counter for a few days or up to a few weeks, until the pickles are to your liking.

Recipes courtesy of Erica Wides (@thechefsmartypants)

 

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