Why Poor Gut Health is The Metabolism Mistake You Can’t Overlook

Why Poor Gut Health is The Metabolism Mistake You Can’t Overlook

Video | Ultra-Processed Foods | Probiotics | Prebiotics | Diet Diversity | Fasting

Your metabolism is the collection of reactions inside your body that convert the foods you eat into energy used to power everything you do, from exercising to breathing. You want it to run uninhibited so you fully utilize the energy you take in. 

Your gut houses trillions of bacteria and other microscopic organisms. There are good and bad bacteria; the mixture of them living inside you makes up your unique gut microbiome and determines your gut health.  

Will improving your gut health directly improve your metabolism? No. We can’t say that yet. While there are some interesting studies, like the famous 2006 study where gut bacteria from obese mice were put into germ-free mice, making them fat, more research is needed to understand this connection fully (1).

However, there is evidence that an imbalanced gut microbiome contributes to weight loss barriers like insulin resistance, poor blood sugar regulation, and inflammation (2) (3) (4).

It is even hypothesized that the bacteria in your gut manipulate your eating behaviors. Basically stated, the bugs in your gut have food preferences of their own, and what they crave, you crave (5).

All these factors make poor gut health the metabolism mistake you cannot overlook. The good news is that you can make improvements. This blog post shares how to give your gut what it needs, so you can get the health and weight control you want. 

Gut Health – At-A-Glance

  • The mixture of good and bad bacteria inside your digestive tract makes up your unique gut microbiome.
  • An imbalanced gut microbiome contributes to weight loss barriers like insulin resistance, poor blood sugar regulation, and inflammation.
  • Ultra-processed foods that are prominent in our modern diet negatively impact gut health. 
  • Artificial sweeteners, a lack of diet diversity, and antibiotics also damage gut health.
  • Improving gut health includes taking a probiotic, eating prebiotic foods, and incorporating intermittent fasting.

Why Poor Gut Health is The Metabolism Mistake You Can’t Overlook [Video]

In this video, you’ll learn…

  • How your health is affected by an imbalanced gut microbiome.
  • Things that contribute to poor gut health.
  • Strategies to help you rebuild your gut health.

Supporting Gut Health is Like Tuning Up an Engine 

The power of your vehicle’s engine is measured in horsepower. It is the rate at which work is done. In your body, your metabolism measures the rate at which work is done. 

One way to get more horsepower out of your vehicle is to give it a tune-up, removing any barriers to performance, like clogged air and fuel filters. This tune-up won’t directly increase horsepower but will allow the engine to run uninhibited. Improving your gut health is like tuning up an engine; your metabolism benefits when optimized through diet, fasting, and pre and probiotics. 

Avoid Ultra-Processed Foods & Drinks

However, modern life works against this goal. There is a level of fun to eating pizza and chips, and burgers and fries, and chasing them down with a Mountain Dew. But these ultra-processed foods are full of refined carbs, added sugars, seed oils, and non-food chemicals. They change the gut microbiota and lead to inflammation and disease. 

ultra-processed foods

The challenge is that these negative changes tend to fly under our radar, so it is easy to get a sense that you are getting away with it. In fact, people can live for years on these junk foods. But you can’t outrun the health consequences of chronic inflammation, and the effect may even be passed down to later generations by changing the way your genes work (6).

Ultra-processed foods are not the only contributor to poor gut health. The use of artificial sweeteners that come in pink, yellow, and blue packets (namely Sweet’N Low, Splenda, and Equal) can alter the gut microbiome, as can a lack of diversity in your diet and antibiotics (7).

Artificial sweeteners, a lack of diet diversity, and antibiotics
 damage gut health.

Antibiotics are not something that you have to avoid, as they are needed from time to time. However, it is good to take steps to restore your gut microbiome after taking them.

How to Promote Gut Health

What you want to promote is microbial richness and diversity. Richness refers to the total number of bacteria in your gut, and diversity refers to the different types of microorganisms that are present. Both are desirable for health benefits.

It is also interesting to note that obese individuals tend to have lower richness and diversity than those of a healthy weight and gain more weight over time (8).


The easiest way to impact gut health is with probiotics, which are living, beneficial bacteria. So taking a probiotic supplement is like sending in reinforcements or more troops to fight the good fight. 

The challenge with probiotics is that they must travel a long distance through your digestive tract. Along that journey, they face stomach acid and other threats to their survival. Therefore, you want to choose a high-quality probiotic.

Things to look for are a probiotic with a protective capsule to help it survive the digestive tract, a probiotic that is cold shipped, protecting it from the heat of transport, and brands that contain an abundance of bacterial species and strains. This is typically noted on the label as CFUs (Colony-Forming Units) or AFUs (Active Fluorescent Units). Seed, Visbiome, and Pure Encapsulations are companies I trust that offer high-quality probiotics. 

I do not recommend buying a probiotic off of the grocery store shelf. These brands have been subjected to heat during transport and storage that can destroy the bacteria. Also, they often lack the diversity that makes them worthwhile. 


While probiotics supply live, beneficial bacteria, prebiotics provide the “food” these bacteria thrive on. 

Prebiotics are a type of fiber that does not get digested, allowing it to reach the colon, where the gut bacteria break it down. This process promotes the production of short-chain fatty acids that reduce inflammation throughout your body and directly feed the cells of your colon, which has a protective effect against colorectal cancer (9)(10).

Prebiotic foods that are lower in carbs include asparagus, garlic, onions, and many nuts and seeds, such as almonds and flaxseeds. 

Lentils, chickpeas, beans, apples, leeks, and Jerusalem artichokes also act as prebiotics but have higher total carbohydrate content. 

Prebiotic Foods

Diet Diversity = Microbiome Diversity

You’ll notice that the best prebiotic foods are carbohydrates. But supporting gut health does not mean you have to eat a high-carb or low-fat diet. Instead, aim to take in a diverse range of foods, and you’ll have a more diverse gut microbiome.

For instance, include foods that you might not be eating now. 

Good choices include fermented foods like kimchi, kombucha, kefir, sauerkraut, and unsweetened yogurt.

Foods rich in polyphenols positively impact your gut. Examples include green tea, coffee, and high-quality olive oil. 

diet diversity

Polyphenols are also abundant in dark chocolate and red wine, but you want to choose wisely. Dark chocolate needs to be at least 70% cacao, preferably 80% and above, with no sugar listed in the top three ingredients. With red wine, enjoy a few glasses a week, but too much alcohol can damage gut health. 

You can also experiment with using resistant starches. As the name suggests, these are starches that resist digestion, making it to the colon, where the good gut bacteria convert them to the beneficial short-chain fatty acids I discussed earlier. 

Foods that contain resistant starch include cooked and cooled potatoes, beans, and green bananas. If you can’t bring yourself to eat resistant starch foods, you can supplement your diet with raw potato starch.  

Raw Potato Starch

If you take in two tablespoons, you’ve reached the level where many studies show benefits, 15 to 30 grams of resistant starch per day. You’ll want to take that daily dose for a few weeks to maximize the benefits of short-chain fatty acid production.

While it is okay to include raw potato starch in a recipe, you want to use it uncooked to get the full benefit of the resistant starch. It has very little taste. You can mix it into yogurt or a smoothie or simply stir it into a glass of water and drink it with a meal. This will also help you feel full longer. 


Feeding your good bacteria makes more good bacteria. There is also evidence that abstaining from food benefits the gut microbiome. While the exact mechanisms are not fully understood, a study that monitored a group of individuals who fasted for 16 hours per day for 30 days of Ramadan, found that they had a significant increase in bacterial diversity compared to the control group (11).


The takeaway is this: by avoiding ultra-processed foods, eating a variety of whole foods in a shortened eating window, and taking a high-quality probiotic, you can positively impact your gut microbiome, removing barriers to an efficiently running metabolism. 

Thank you for reading and have a wonderful week!


(1) Turnbaugh, Peter J., et al. “An obesity-associated gut microbiome with increased capacity for energy harvest.” nature 444.7122 (2006): 1027-1031.

(2) Caricilli, Andrea M., and Mario JA Saad. “The role of gut microbiota on insulin resistance.” Nutrients 5.3 (2013): 829-851.

(3) Gérard, Céline, and Hubert Vidal. “Impact of gut microbiota on host glycemic control.” Frontiers in endocrinology 10 (2019): 29.

(4) Al Bander, Zahraa, et al. “The gut microbiota and inflammation: an overview.” International journal of environmental research and public health 17.20 (2020): 7618.

(5) Alcock, Joe, Carlo C. Maley, and C. Athena Aktipis. “Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms.” Bioessays 36.10 (2014): 940-949.

(6) Shi, Zumin. “Gut microbiota: An important link between western diet and chronic diseases.” Nutrients 11.10 (2019): 2287.

(7) Suez, Jotham, et al. “Artificial sweeteners induce glucose intolerance by altering the gut microbiota.” Nature 514.7521 (2014): 181-186.

(8) Le Chatelier, Emmanuelle, et al. “Richness of human gut microbiome correlates with metabolic markers.” Nature 500.7464 (2013): 541-546.

(9) Canani, Roberto Berni, et al. “Potential beneficial effects of butyrate in intestinal and extraintestinal diseases.” World journal of gastroenterology: WJG 17.12 (2011): 1519.

(10) Ríos-Covián, David, et al. “Intestinal short chain fatty acids and their link with diet and human health.” Frontiers in microbiology 7 (2016): 185.

(11) Larrick, Jasmine W., Andrew R. Mendelsohn, and James W. Larrick. “Beneficial gut microbiome remodeled during intermittent fasting in humans.” Rejuvenation Research 24.3 (2021): 234-237.

About the Author

Becky Gillaspy, DC, is the author of The Intermittent Fasting Guide and Cookbook. She graduated Summa Cum Laude with research honors from Palmer College of Chiropractic in 1991. 

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