Do You Really Want a Hunter-Gatherer Microbiota?

In a recent article I wrote for a peer-reviewed journal, I critically examined prevailing health advice on adopting the diet and lifestyle of hunter-gatherer tribes to improve digestive health, immune function, and biome diversity.

If you need help with your biome, click here.


Do You Really Want a Hunter-Gatherer Microbiota?

Dr. Michael Ruscio: The ancestral diet and health movement has been growing in popularity. Its message is to improve gut health and biome diversity by adopting the habits of our hunter-gather ancestors. This means increasing prebiotics and fiber in the diet, as well as focusing less on hygiene and spending more time outdoors with animals and soil-based activities.

But does this perspective make sense for everyone? Perhaps we should meet the modern gut and biome where it is instead of molding it to the practices of a distant culture. This is because bacteria that may be beneficial for an African biome may cause inflammation in the Western gut.

The biome is formed at age 3, so an ancestral lifestyle and dietary intervention at a later age may be poorly tolerated, or even serve as an insult to the immune system. Studies have shown that IBS and IBD patients have increased symptoms with a diet high in prebiotics and fermentable fibers. And the impact of supplemental fiber, including resistant starch, on conditions like colorectal cancer appears to be minimal according to research.

In a recent article I wrote for a peer-reviewed journal, I look at the impact of ancestral lifestyle and diet advice on the modern, Western biome from an evidence-based perspective. You can read the entire article here. The summary is below.

The current hypothesis is that our modern biome suffers due to a hygienic, indoor lifestyle, as well as C-section births, poor diets, and modern medical interventions, such as antibiotics. This degrades the immune system and leads to a rise in autoimmune disease and inflammatory conditions. For hunter-gather tribes, these conditions are virtually nonexistent.

But what works for tribal populations won’t necessarily work for Westerners.

It should first be clarified that many ancestral tribes do not eat diets that are high in fiber and fermentable carbohydrates, instead deriving many of their calories from animal fat and protein.

Patients who suffer with digestive complaints like SIBO or IBS have unique dietary requirements to resolve symptoms and feel healthy and vibrant.

With such patients, I use a low FODMAP diet, which is a lower carb, lower fermentation approach. This is combined with either antibiotics or antimicrobial herbs, or in some cases, a half or full elemental diet. Only after full remission and a successful reintroduction of higher FODMAP foods do we take the last step of adding fiber, prebiotics, and resistant starch to the maintenance protocol.

Lower carb diets, such as the low FODMAP/SCD or Paleo/Autoimmune Paleo, have also shown promise in improving metabolic conditions such as diabetes or heart disease.

Lifestyle factors can also boost biome diversity, such as spending time outdoors at the beach or hiking, lowering stress, reducing antibiotics use, appropriate movement, and adequate sleep. A diverse diet creates a diverse biome, so building tolerance to a wide variety of foods is the aim of my functional medicine approach.

In conclusion, balancing the modern biome means taking culture and circumstance into account. The ancestral movement can inspire a healthier lifestyle, but adopting a strategy that works for a much different population is not advisable. Hopefully future research in the area of the biome will steer us away from generic recommendations and teach us to tailor biome rebalancing to the population at hand.

If you need help with your biome, click here.

What do you think? I would like to hear your thoughts or experience with this.

Dr. Ruscio is your leading functional and integrative doctor specializing in gut related disorders such as SIBO, leaky gut, Celiac, IBS and in thyroid disorders such as hypothyroid and hyperthyroid. For more information on how to become a patient, please contact our office. Serving the San Francisco bay area and distance patients via phone and Skype.


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