Image Of A Hand Holding Mixed Nuts That He Will Eat To Improve Gut Health

How to Improve Gut Health During the Holidays

BY Phil White

These three tips will help you feel lighter and healthier during the holidays — even when feasting.

With COVID cases soaring, nasty respiratory infections on the rise, and the usual cold and flu doing the rounds, your immune system is facing a stern test this winter. One of the keys to keeping yourself and your family healthy as you head into the holidays is preserving your gut health, and yet the typical festive diet is hardly conducive to that. This article will tackle how to improve gut health over the holidays. Let’s look at which foods and beverages to limit and those you should load up on to help ward off sickness and promote overall well-being.

1. Find Fermented Foods

Historically, the aim of fermenting foods was to preserve them, particularly before refrigeration was a thing. But more recently, science has shown that they also support optimal gut health. 

Researchers from Stanford School of Medicine compared two groups over 10 weeks. The first followed a high-fiber diet while the second incorporated fermented products like kimchi, kombucha, and pickled vegetables. The second group had an increase in the diversity of gut microbiota and had lower levels of 19 inflammatory markers related to immunity. The researchers noted that while the high-fiber group didn’t experience the microbiome changes they hypothesized over the 10-week study period, eating a lot of fiber for a longer period might.   

Dairy-based fermented foods also appear to be beneficial to gut health. A review released via The American Journal of Clinical Nutrition stated that “the benefits of yogurt consumption to gastrointestinal function are most likely due to effects mediated through the gut microflora, bowel transit, and enhancement of gastrointestinal innate and adaptive immune responses.” The probiotic strains in Greek yogurt and varieties like skyr include Lactobacillus, Streptococcus, and Bifidobacterium. Some brands, like Icelandic Provisions, offer heirloom strains that are hard to find anywhere else. If you have a dairy allergy or just don’t eat it, then many almond yogurts made from milk alternatives also contain probiotic cultures.  

2. Prioritize Prebiotics for Gut Health

Probiotic supplements have become big business and food options like the fermented ones we already mentioned have broken out of the niche category and into the mainstream. Yet, as beneficial as these are to gut health, you shouldn’t overlook the lesser-known prebiotics, which are essentially a source of fuel for good gut bacteria. 

While prebiotic pills are becoming more popular, Dr. Justin Sonnenburg, a professor of microbiology and immunology at Stanford University, told The New York Times that because there are so many bacteria species in the human gut, “it’s very difficult to imagine how putting one purified prebiotic into this community could foster the kind of biodiversity you need in your gut microbiome.”  

Instead, he suggested eating a broad range of fresh foods. Solid prebiotic picks include green bananas, artichokes, onions, asparagus, and garlic. A study published in Molecular Psychiatry found that combining such prebiotic, fiber-rich foods with fermented ones in a so-called psychobiotic diet (i.e., one that includes foods linked to mental health) for four weeks increased the activity of certain gut microbes among participants. They also reported experiencing lower stress levels. 

In an article for The Conversation, the study co-author explained that this might be because such nutrients impact the gut-brain axis, which is the mechanism via which “the emotional and cognitive centres in our brain are closely connected to our gut.” 

3. Go With Greens and Nuts to Improve Gut Health

Researchers from Australia and the UK explored how the human body uses green leafy vegetables to support gut health. They reported identifying a unique enzyme that feeds “good” bacteria in the intestines after consuming the sugar molecule sulfoquinovose in greens. “We speculate that consumption of this specific molecule within leafy greens will prove to be an important factor in improving and maintaining healthy gut bacteria and good digestive health,” study co-author Dr. Ethan Goddard-Borger explained in a ScienceDaily article.

Kale, spinach, watercress, broccoli, and kale are all rich sources, even if your grandma insists on drowning them in a creamy sauce for Christmas dinner — which will also increase the uptake of fat-soluble vitamins.

Such greens are also rich in fiber, which is the preferred energy source for probiotics. Another way to increase your fiber intake this holiday season is to eat more nuts. A study published in Nutrients looked at the results of eight previous studies and concluded that almonds, walnuts, and pistachios increased the activity of Clostridium, Dialister, Lachnospira, and Roseburia bacteria. “Nuts contain fibre, unsaturated fatty acids and polyphenols that may impact the composition of the gut microbiota and overall gut health,” the authors wrote.

While nobody wants to adopt a puritanical approach to eating during the holidays, you don’t have to take the joy out of your festive favorites to preserve your gut health. Instead, just try to keep excess sugar consumption to a minimum, as studies have shown that this can compromise your microbiome. Then, seek out foods rich in probiotics and prebiotics; eat extra fiber-packed fruits, vegetables, and nuts; and add in a few fermented products. That should be enough to maintain your microbiome and overall wellness.  


(2016, February 15). Sweet discovery in leafy greens holds key to gut health. Retrieved from 

Adolfsson, O. et al. (2004, August). Yogurt and gut function. Retrieved from 

Berding, K. et al. (2022, October 27). Feed your microbes to deal with stress: a psychobiotic diet impacts microbial stability and perceived stress in a healthy adult population. Retrieved from 

Blum, D. (2022, October 28). Are Prebiotics Important for Gut Health?. Retrieved from 

Creedon, A.C. et al. (2020, August 6). Nuts and their Effect on Gut Microbiota, Gut Function and Symptoms in Adults: A Systematic Review and Meta-Analysis of Randomised Controlled Trials. Retrieved from 

Cryan, J. (2022, October 27). Fermented foods and fibre may lower stress levels – new study. Retrieved from 

Wastyk, H.C. et al. (2021, July 12). Gut-microbiota-targeted diets modulate human immune status. Retrieved from

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About Phil White
Phil White is an Emmy-nominated writer and the co-author of The 17 Hour Fast with Dr. Frank Merritt, Waterman 2.0 with Kelly Starrettand Unplugged with Andy Galpin and Brian Mackenzie. Learn more at and follow Phil on Instagram @philwhitebooks.

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