Why Your 'Healthy' Diet Might Be Making You Sick: The RNA Revolution in Your Gut
Viome co-founder Dr Momo Vuyisich explains why reading the microbiome's RNA, what your microbes are actually doing, is far more useful than reading DNA, which only tells you who is there. The bigger message: there is no universally healthy diet. The right question is not whether a food is good, but which people it is good for, and the way to find out is to measure your own physiology rather than follow blanket rules.
Overview
In this hour-long conversation on Modern Healthspan, Dr Momo Vuyisich, former lead scientist at Los Alamos National Laboratory and co-founder of Viome, unpacks why RNA is a far more useful window into health than DNA. DNA tells you the potential of a cell or which microbes are present, but RNA tells you what those cells and microbes are actually doing right now, distinguishing a healthy liver from a fatty one, or IBD in remission from a flare.
Viome uses metatranscriptomics to quantify more than 10,000 microbial biomarkers, such as the keystone molecule butyrate, and tunes the gut by adjusting the raw materials the microbes feed on, much like brewing beer. From this, the company computes today's risk for a growing list of chronic diseases and pairs each finding with what is wrong and how to address it. A central theme is that there is no universally healthy diet: the same food can help one person and harm another, as the carnitine-to-TMAO story shows.
Vuyisich argues that environment and nutrition, not DNA, drive most chronic disease, and recommends a testing foundation, retested roughly every six months, covering the microbiome, food sensitivities, standard blood panels, heavy metals, hormones, mycotoxins, and biological age. He closes with his vision of a focused, Manhattan Project style effort to find the root causes of chronic disease.
Key quotes
5RNA tells you what is the function of a cell, not what is the potential.
There is no set of foods in given amounts that are going to be good for everyone. That doesn't exist.
On average cocoa reduced blood pressure, but you don't know where you are on that spectrum. You could actually be being harmed.
Your DNA doesn't do anything, it's just a physical static object. You build your body from your nutrients.
When a person gets diagnosed today, it's bad luck. But it's not bad luck, it's biochemistry we don't yet understand.
Key ideas
9RNA reveals function, DNA only potential
The same DNA sits in your liver, kidneys and brain, and stays identical from health to disease. RNA differs sharply between organs and between a healthy and a sick state, so it tells you what is actually happening.
Reading what microbes do, not just their names
DNA sequencing lists which microbes are present, but people with IBD keep the same microbiome through remission and relapse. RNA, via metatranscriptomics, distinguishes those states because it captures function.
More than 10,000 microbial biomarkers
Viome quantifies molecules like the keystone compound butyrate and compares them to a large reference cohort to define healthy ranges, then identifies the raw materials that drive each one.
The gut works like brewing beer
Just as yeast makes more ethanol when fed more malted barley, gut microbes produce more of a beneficial molecule when given the right micronutrients. Tuning the inputs tunes the output.
Feed the microbes you already have
If a beneficial microbe already lives in your gut, there is little point adding it as a probiotic. Prebiotics, the right fibers, feed it instead, though complex cross-feeding among about 1,200 species makes this far from simple.
Today's risk, plus what to fix
Because RNA reflects your physiology now, Viome reports risk for a growing set of chronic diseases and, for each finding, states what is out of balance and how to address it, years before symptoms appear.
There is no universally healthy diet
Any ingredient has studies showing both benefit and harm because people respond differently. The better question is which people a food helps and which it harms, including effects that vary by sex and age.
Carnitine, TMAO and personalization
Carnitine supports mitochondria but is converted by some people's gut microbes into TMA and then TMAO, a driver of cardiovascular disease, an effect blunted by estrogen before menopause. Whether it helps depends on your biology.
Inside the biological age clock
The clock reads about 1,263 RNA transcripts drawn from stool, blood and saliva, each weighted by a machine-learned coefficient, giving a stable measure to track over time as you change your habits.
Practical takeaways
7- 1
Environment beats genetics 37:00
DNA contributes on average roughly 10 percent to chronic disease. Nutrition and environment do most of the work, so focus your effort where the leverage is.
- 2
Retest about every six months 40:00
The stool microbiome does not change meaningfully until around five to six months, so retesting twice a year is a sensible rhythm.
- 3
Build a testing foundation 42:30
Combine microbiome testing with food sensitivity and allergy testing, and use the full blood panel most insurers cover once a year at no cost.
- 4
Check the overlooked risks 44:00
Ask about heavy metals, hormones, and mycotoxins from mold. Any one of these, if elevated, can undermine health no matter how well you eat, sleep or exercise.
- 5
Measure before you supplement 47:00
Popular supplements like carnitine can help or harm depending on your physiology. Without data you are guessing, so test first rather than following the trend.
- 6
Track biological age, not just birthdays 51:30
Biological age reflects your true health state better than the calendar and lets you see whether nutrition, exercise, sleep and stress management are actually moving the needle.
- 7
Make whole foods your foundation 58:00
An organic, whole-food, plant-forward base helps you avoid pesticides, preservatives and antibiotic-laden non-organic meat and dairy that erode microbiome resilience over decades.
Topics & chapters
15RNA versus DNA, and meet Dr Vuyisich
The episode opens on why RNA reveals function while DNA only shows potential, and introduces the former Los Alamos scientist behind Viome.
Why he founded Viome
Neither academia nor pharma is built to prevent disease, so he set out to find and reverse the root causes of chronic illness, motivated partly by his own autoimmune condition.
Will pharma turn preventive?
GLP-1 and next-generation peptides may shift pharma toward prevention, but chiefly for metabolic disease, not conditions like Parkinson's or cancer.
DNA versus RNA in the microbiome
Stool DNA lists which microbes are present, but RNA reveals what they are doing, using the analogy of different organs sharing identical DNA.
Metatranscriptomics and IBD states
People with IBD keep the same microbiome through remission and relapse, yet RNA can tell those states apart, and even separate IBD from IBS.
Butyrate, biomarkers and the beer analogy
Viome quantifies more than 10,000 microbial biomarkers and tunes their output by adjusting the raw materials, exactly like feeding yeast barley to brew beer.
Prebiotics and predicting disease early
Feed the beneficial microbes you already have rather than adding probiotics, and use RNA to flag today's risk for a growing list of chronic diseases.
There is no universally healthy diet
Decades of trials show every food helps some people and harms others. The cocoa and blood pressure example shows why averages mislead.
Carnitine, TMAO and personalized risk
Carnitine can become heart-harming TMAO in some people, modified by sex, menopause and other risk factors, so measurement beats guessing.
DNA versus environment
DNA plays a minor role on average in chronic disease while nutrition dominates. You build your body from nutrients, not from DNA.
How often to test yourself
The microbiome shifts only after five to six months, so retest about every six months, more often from your forties onward.
The testing foundation and overlooked risks
Microbiome, food sensitivities, standard blood panels, heavy metals, hormones and mycotoxins form a practical foundation everyone should consider.
The food sensitivity frontier
Food sensitivity science is still weak. Viome plans to invest heavily to understand why the same sensitivity harms one person and not another.
Inside the biological age clock
About 1,263 RNA transcripts from stool, blood and saliva, machine-selected and weighted, produce a stable biological age, validated across cultures.
A Manhattan Project for chronic disease
He argues for a single, focused effort to find root causes, and closes on the aging gut, meat versus plants, and where to learn more about Viome.