Part 2 of interview with Cass Nelson-Dooley of Metametrix

The following is Part 2 of the interview with Cass Nelson-Dooley, Clinical Consultant at Metametrix, with contributions by Mr. Tony Hoffman

Part 1 can be read here

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Gut-smells body odor

Are you amazed that there are people around who smell of gut smells?

Yes, I imagine that must be difficult to deal with. I would compare it to the example of eating garlic. The sulfur compounds from garlic are liberated by chopping and chewing and these sulfur compounds emanate from the mouth and even the skin for some time afterward.

What causes fecal smells? (i.e. what does feces actually smell of and why)

The smell of feces comes from short chain fatty acids (SCFAs) and bacteria like E. coli. All the SCFAs have strong smells. Butyric acid is an SCFA and it smells like feces and even like body odor. E .coli has more of a mousy odor.

Do you have a good idea what microbes in particular cause gas smells? Do you have any theories as to how someone could smell of gut smells through their pores/breath?

It is likely that bacterial overgrowth occurs in the small bowel and the products are absorbed and then emanate from the skin. I wouldn’t expect that the malodorous products would be absorbed from the colon. If someone has an overgrowth of Disulfovibrio, there may be a sulfur smell. If someone has an overgrowth of Pseudomonas sp., the smell may be sweeter (grape-like), but still sickly sweet. There is a whole group of sulfur-producing bacteria. Citrobacter freundii produces sulfur. Additionally, if the person suffers with maldigestion then food will undergo fermentation and this produces putrefactive compounds such as putrescine. While blood borne body odor is likely multi-factorial, at least for some patients, healing the bowel and cleaning up the diet could provide some relief.

Do you think with gut-related metabolic body odors, it's likely an enzyme is saturated? For instance a drug metabolizing enzyme? Any thoughts as to which one(s)? Any thoughts as to a scenario?

In addition to dysbiosis, I think it could be enzyme saturation or lack of vitamin and mineral cofactors. Metabolic diseases such as amino acidurias or organic acidurias have been characterized by strange odors, especially in the urine. These disorders occur due to lack of an enzyme, poor function of an enzyme, or low levels of cofactors causing the enzyme to malfunction. The result is too much of the byproducts, which can be smelly in high concentrations.

Does leaky gut mean 'leaky small intestine'? Do you think leaky gut or 'leaky colon' is likely a factor?

Leaky gut is often involved in cases of dysbiosis. It could be a factor in people with blood borne body odor, but I wouldn’t know for sure without an IgG4 food antibody test. Intestinal permeability, or “leaky gut,” has been implicated in inflammatory bowel diseases such as Crohn’s disease, non-alcoholic fatty liver disease, alcoholic liver disease, food allergy, acute pancreatitis, celiac disease, multi-organ dysfunction, and autism. According to the leaky gut hypothesis, genetic predisposition to poor intestinal barrier function, coupled with stressors such as NSAIDS or alcohol, can result in permeation of the intestinal mucosa. Antigens and bacteria are then able to cross the intestinal membrane and enter circulation where the immune system launches an attack against the antigens.

What kinds of tests would you recommend for a person suffering with blood borne body odor?

Without knowing a detailed history on the patient, I would recommend the GI Effects, the Organix, and the 40 amino acids. I recommend those lab tests because of the likely involvement of gut dysbiosis and abnormal SCFAs, vitamin need, and metabolic diseases involving amino acids and organic acids. I would also recommend IgG4 Food Antibody testing, especially if the person has gut, skin, or autoimmune symptoms.

Trimethylaminuria

Do you think a particular type of bacteria are responsible for gut trimethylamine production? Is it likely the same one thought to cause bacterial vaginosis (Gardnerella)?

Yes. The more smelly compounds like trimethylamine and hydrogen sulfide are not products of human metabolism, but they are produced by several bacteria under certain conditions. They tend to be strict anaerobes that could dwell in the colon or the vagina.

There is a 'diagnosis' of 'Secondary TMAU', where the enzyme involved is deemed fine, but the person has too much trimethylamine. Do you have any suggestion as to how to kill off the TMA-producing bacteria in particular?

The first thing to do is lower protein intake and improve protein digestion to reduce undigested nitrogenous substrates (amino acids) that must be present to form ammonia. Perhaps water or juice fasting could be beneficial in these instances as it can change the microbial content of the gut. If you don’t feed the colonic bacteria, they can’t grow and produce strange products.

Some feel that trimethylamine can produce a wide range of odors. Do you think trimethylamine could cause the wide range of gut smells on its own?

No. However it can be a component in complex mixtures of products that are responsible for the varying odors among individuals.

Final Questions

What do you think of the quality of probiotics on the market and are there any brands of probiotics you recommend ?

We are impressed with Klaire Labs probiotic and prebiotic formulas. I also like Custom Probiotics and a high dose probiotic called VSL#3. Designs for Health has a good probiotic product as well.

Is taking prebiotics on its own a good idea ? And which type of prebiotic do you feel is best ?

Fruits and vegetables are a great source of fiber (prebiotics). Other ideas are inulin, xylooligosaccharides, larch arabinogalactans, and beta glucan.

Is there general treatment advice for 'suspected' dysbiosis or does it vary too much ? For instance, take nystatin and metronidazole in a 'scorched earth' policy ?

I think the “4R Protocol” is the most general treatment advice and it’s comprehensive, but every doctor has a different approach and dysbiosis treatment should be tailored to the patient.

Treatment using 4 “R” Protocol for Intestinal Health from the GI Effects Interpretive Guide

Remove offending foods, medications, gluten (if sensitive) and reduce poor quality fats, refined carbohydrates, sugars, and fermented foods (if yeast is present). Consider antimicrobial, antifungal, and/or antiparasitic therapies in the case of opportunistic/pathogenic bacterial, yeast, and/or parasite overgrowth (see below for specific recommendations).
Replace what is needed for normal digestion and absorption such as betaine HCl, pancreatic enzymes, herbs that aid in digestion such as deglycyrrhizinated licorice and marshmallow root, dietary fiber, and water.
Reinoculate with favorable microbes (probiotics such as Lactobacillus sp., Bifidobacter sp., and Saccharomyces boulardii). To enhance the growth of the favorable bacteria, supplement with prebiotics such as inulin, xylooligosaccharides, larch arabinogalactans, beta glucan, and fiber.
Repair mucosal lining by giving support to healthy intestinal mucosal cells, goblet cells, and to the immune system. Consider L-glutamine, essential fatty acids, zinc, pantothenic acid and vitamin C.

Why does the intake of probiotics sometimes produce bloating and gas in some people and not in others?

Not all people react the same to probiotics because it depends on their microbial populations. When a person has a poor diet (high simple sugars, low fiber), taking probiotics can produce gas. However, this usually goes away with time. If the patient increases complex carbs and decreases simple sugars that often decreases any gas and bloating brought on by the probiotic. When there are unexplained reactions to probiotics or prebiotics, it is a good idea to run an Organix test, a GI Effects test, or food antibody test to identify underlying imbalances.

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Part 1 can be read here