Eating for Gut Health and Improving Bacterial Diversity

Dr. David Wiss

August 14, 2022

Gut Health

Gut health is the missing link in the relationship between nutrition and mental health. Controversy on how to best treat gut-related issues still exists. For example, some practitioners focus on eliminating foods to “starve” off opportunistic bacteria, and others aim to improve gut health by feeding the beneficial microbes.

Both approaches have merit and are usually necessary, in combination. If you have persistent gut-related issues, there’s lots of good supplements on the marketplace that can help you. Reach out for help, but try making some nutritional changes first.

One area where research does agree is concerning bacterial diversity. Approximately one thousand diverse species are residing in the human gut. Having a wider range of bacterial species is associated with health benefits, including weight regulation [1] and depressive symptoms [2]. Improving bacterial diversity is one of the most straightforward approaches to using nutrition for mental health.

Alcohol and drug use negatively affect gut bacteria [3-6], with reductions in beneficial species and overgrowth of others, which is known as “gut dysbiosis.” Some of these changes stem from increased gut lining permeability, sometimes referred to as “leaky gut.”

Additionally, many commonly used psychotropic medications negatively affect bacterial diversity [7,8], which may explain some of their side effects, including weight gain. If you’re on medications or have any history of alcohol or drug use, then you need to pay even more attention to your gut health.

Nutrition for the Gut-Brain Axis

You’re hopefully eating from all food groups multiple times a day. This is the first step in improving bacterial diversity. You might be taking a probiotic supplement which is generally a great idea. For a probiotic recommendation specific to your needs, reach out for assistance. Now is the time to start checking in with your hunger and fullness cues and practicing Mindful and Soulful Eating.

There are also important links between artificial sweeteners and gut health. To summarize, most artificial sweeteners reduce bacterial diversity. Over time, this might compromise communication along the gut-brain axis. It’s best to avoid consuming artificial sweeteners, including stevia and monk fruit.

If you’re drinking chia water every day, you’re doing one of the best things you can do for your gut. Chia seeds are an excellent source of soluble fiber, which colonic bacteria feed on. Don’t be shy with the chia seeds. Eating (or drinking) chia seeds may help reduce inflammation that stems from gut dysbiosis.

The next step is to eat beans on most days of the week. This includes chickpeas, black beans, lentils, or any other bean you enjoy. If beans are difficult on your system, start with hummus. Canned or boxed can work fine, especially if you rinse them of any added salt. If you’re not getting your beans, nuts, and seeds several times per day, now is the time to ramp up those efforts. Eating the right kinds of soluble fiber for gut health cannot be overemphasized. Other high fiber foods for gut health are outlined below.

Other Known Gut Health Strategies to Include Daily:

• Fermented vegetables such as sauerkraut or kimchi. Use it as a small part of your plate or your bowl.
• Fermented dairy products such as yogurt or kefir. If there’s any dairy products to emphasize, these are the ones. And there’s also plenty of non-dairy versions of these now on the marketplace. Full-fat and unsweetened is the best route.
• Bone broth, which contains collagen protein and gelatin, and includes the amino acid glutamine, all of which are beneficial to the gut barrier. Plant-based eaters can find glutamine supplements not from animal sources.

What are the Foods Exceptionally High in these Prebiotic Fibers?

• Fruits include: raspberries, bananas, apples, pears, kiwi (don't forget to eat the kiwi skin!).
• Vegetables include: Brussel's sprouts, cabbage, artichoke, asparagus, onion, leeks, jicama.
• Grains include: barley, oats, quinoa, millet.
• Beans include: peas, chickpeas, lentils, black beans, white beans, pinto.
• Nuts include all nuts, but make sure to eat the skin especially on the: almonds, cashews, Brazil nuts, pistachio.
• Seeds include: chia, pumpkin seeds, sunflower seeds, flax seeds.

The next step is to increase bacterial diversity by increasing the variety in your diet. In other words, by consuming a wide range of plant fibers, there may be a wider range of species that reside in your gut. This may seem difficult to those with a limited selection of foods, but trust that your gut will thank you. This is a key tenet to anti-inflammatory eating.

Remember to challenge the idea that calories are the best barometer for food choices. If you’re avoiding foods based on calories alone, you may be working against efforts to improve your bacterial diversity. Gut health is the future of mental health. Feed your microbes and let them feed you back. Your second brain will thank you.

1. Menni C, Jackson MA, Pallister T, Steves CJ, Spector TD, Valdes AM. Gut microbiome diversity and high-fibre intake are related to lower long-term weight gain. Int J Obesity. 2017;41(7):1099–105.
2. Limbana T, Khan F, Eskander N, T L, F K, N E. Gut Microbiome and Depression: How Microbes Affect the Way We Think. Cureus J Medical Sci. 2020;12(8):e9966.
3. Salavrakos M, Leclercq S, Timary PD, Dom G. Microbiome and substances of abuse. Prog Neuro-psychopharmacology Biological Psychiatry. 2020;110113.
4. Wang S-C, Chen Y-C, Chen S-J, Lee C-H, Cheng C-M. Alcohol Addiction, Gut Microbiota, and Alcoholism Treatment: A Review. Int J Mol Sci. 2020;21(17):6413.
5. Vila AV, Collij V, Sanna S, Sinha T, Imhann F, Bourgonje AR, et al. Impact of commonly used drugs on the composition and metabolic function of the gut microbiota. Nat Commun. 2020;11(1):362.
6. Xu Y, Xie Z, Wang H, Shen Z, Guo Y, Gao Y, et al. Bacterial Diversity of Intestinal Microbiota in Patients with Substance Use Disorders Revealed by 16S rRNA Gene Deep Sequencing. Scientific Reports. 2017;7(1):3628.
7. Cussotto S, Clarke G, Dinan TG, Cryan JF. Psychotropics and the Microbiome: a Chamber of Secrets…. Psychopharmacology. 2019;236(5).
8. Tomizawa Y, Kurokawa S, Ishii D, Miyaho K, Ishii C, Sanada K, et al. Effects of Psychotropics on the Microbiome in Patients with Depression and Anxiety: Considerations in a Naturalistic Clinical Setting. Int J Neuropsychoph. 2020;pyaa070-.