Gargling is a great way to shift the balance of bacteria in the mouth. While an antiseptic gargle like iodine or hydrogen peroxide can battle infections like a pro, it also can wipe out your good bacteria. From grandma’s salt water rinse, to Listerine®, probiotics, essential oils, and more, figuring out what to gargle with can be a trick. In this blog, clinicians and consumers will learn what gargle solutions are best and worst, when you need them, when you don’t, and how much to use. Most of all, we will talk about how to preserve the oral microbiome- one of your best defenses against harmful infections and chronic diseases.

Thank you to our sponsor, Riven, for making this blog possible.

The Problem with Antibiotics and Antiseptics

The oral microbiome is a bustling center of activity. Bacteria and other microorganisms constantly grow there. Even if you dumped antibiotics into your mouth regularly, bacteria would start growing as soon as you stopped. And the antibiotic-resistant bacteria would never stop growing! What we eat, drink, medications we take, when we brush our teeth, and when we use toothpaste, mouthwashes, or gargles—at all times we are continuously shaping our oral microbiomes.1

Think of it as a constant dance. You can reduce bacteria biofilms with the above methods, but they never go away. You can obliterate them with harsh antimicrobial products. They will go away, but they come back stronger and in different proportions than before. Even applying antibiotics to the mouth lining only reduces bacteria for a matter of hours.2 In a nutshell: Resistance is futile.

“Dental plaque biofilm cannot be eliminated. However, the pathogenic nature of the dental plaque biofilm can be reduced by reducing the bioburden and maintaining a normal flora with appropriate oral hygiene methods.”3

You have a champion in your corner, one who can easily prevent nasty oral infections- it’s called the oral microbiome. It’s the collection of microorganisms in your mouth that boosts your immune system and improves your health. Ignored for centuries, the oral microbiome can protect us from harmful pathogenic bacteria. The problem is that the majority of all research to date has looked only at how to kill mouth bacteria. Almost nobody has measured the good bacteria in our mouths and how to preserve them- the innocent bystanders of antibiotic toothpastes, mouthwashes, and antiseptic gargles.1 There is much more to research and learn in this area.

Photo by Mikhail Nilov

The goal then is to foster a healthy oral microbiome with diet, probiotics, prebiotics, vitamins for oral health, and non-toxic dental hygiene. A healthy collection of mouth microbes can ward off infections. Harsh antimicrobials should only be needed occasionally when the oral bacteria are out of balance, causing cavities, gum disease, or worse.

“Antiseptic” describes a substance that kills microorganisms to reduce infection,

usually applied to the surface of the body.

 

 

Benefits of Gargling

 

There are many reasons to gargle and lots of different gargling solutions to choose from: salt water, hydrogen peroxide, iodine, essential oils, and more. Gargling is a great at-home remedy for sore throats. Some of my earliest memories are my grandmother having me gargle with salt water. And when my daughter has a sore throat, what do I reach for?

Respiratory illnesses often start with congestion and sore throat, making a gargle a welcome and soothing therapy for children and adults. Gargling can help with wound healing in the back of the mouth or throat. Gargling can really hit the spot if you are getting recurrent sore throats or dysbiosis of the throat (an imbalance of microorganisms). Gargling is a regular part of Japanese culture and many studies have been done on gargling and illness prevention in Japan.4

It’s not just a folk remedy. Gargling can reduce lower respiratory tract infections such as pneumonia, which kill hundreds of thousands of people every year. The mouth and throat are a breeding ground for viruses and bacteria. Attacking them there, before they have a chance to cause full-blown disease in the lungs, is an actual medical strategy. Researchers say it is a safe and affordable way to head off upper respiratory infections before they move to the lower respiratory tract, where they can be deadly in vulnerable people.4

Gargling can fight pneumonia and lung infections.

Antiseptic gargling solutions piqued my interest during the COVID pandemic. Indeed, the mouth and the oral microbiome could influence how sick someone got from SARS-CoV-2 and if it would kill them. Gargling with an antiseptic was recommended to reduce the spread of COVID. In India, a 1% solution of povidone-iodine as an antiseptic mouthwash/gargle, nasal drop, and eye drop reduced COVID hospitalizations by 84%, deaths by 88%, and viral clearance by 26-fold.5-7  Other experts recommended gargling with a 1% hydrogen peroxide solution to prevent the spread of COVID. On the flip side, having a healthy mouth with a healthy oral microbiome reduced the risks of this respiratory virus.8

The mouth is a critical player in lung infections. What we breathe in from our mouth can infect the lungs and set off inflammation. So, keeping the mouth and throat healthy is critical for keeping the lungs healthy. But how we keep our mouths healthy is up for debate.

Mouthwash is No Friend to the Oral Microbiome

 

There is a lot of overlap between mouthwashes and gargling solutions. Mouthwash isn’t the golden child it used to be. It is often used to promote white teeth, get rid of bad breath, and just in general to use as part of a “minty-fresh” oral health routine. But some dental experts, like Dr. Mark Burhenne, DDS, think mouthwash is one of the worst things you can possibly do for your mouth. While mouthwash may leave you feeling like you have a fresh and healthy mouth, it’s not so. Mouthwashes often contain essential oils, fluoride, alcohol, or peroxide.

 

Here are the ways mouthwash can do more harm than good.

  • Kills good mouth bacteria
  • Dries out the mouth
  • Depletes the mouth of nutrients found in saliva
  • Damages mouth tissue and teeth
  • Contributes to bad breath and cavities

Read Dr. Mark Burhenne’s blog above to learn the ingredients you should avoid in mouthwash.

Multiple studies show that mouthwash can actually increase a person’s blood pressure. That may sound strange, but friendly oral bacteria can lower your blood pressure by helping your body make a substance called nitric oxide.9 When people used antiseptic mouth wash to kill off some of their oral microbiota, the bacteria could no longer help with nitric oxide production, and their blood pressure increased! Mouthwash isn’t just bad for the microbiome, it’s bad for heart health, too.

Mouthwashes and mouth rinses have been studied extensively and they often use the same ingredients as gargling solutions. I sometimes refer to the research on mouthwashes when making conclusions about common ingredients in gargle products.

 

Does Gargling with Salt Water, Iodine, or Peroxide Kill Good Bacteria in the Mouth?

 

Yes. Gargling solutions are going to suppress the oral microbiome- even tap water or salt water will do it for a short time.2,4 Because few studies measure good bacteria, there is not a lot of strong evidence to prove it. However, it stands to reason that if these gargling solutions decrease plaque, kill bacterial pathogens, and decrease inflamed gums (which come from bacterial overgrowth), they also kill good bacteria. And as mentioned earlier, even simple oral hygiene measures like brushing teeth decrease mouth bacteria.

Take a look at this table that shows broad-spectrum antimicrobial activity for a wide range of gargles including salt water (sodium chloride), iodine, and essential oils. They act against bacteria, viruses, fungi, and parasites. The good news is that these gargles kill harmful bugs. The bad news is that they probably kill the good ones, too.

 

From Ahmad, L. (2021) “Impact of Gargling on Respiratory Infections,” All Life, 14:1, 147-158.4

 

When to Use Antiseptic Gargles

 

Antiseptic gargles (or mouthwashes) are sometimes desperately needed, even if good mouth bacteria are going to take a hit. For example, a high-risk patient with a recent confirmed SARS-CoV-2 (COVID) infection could benefit from an iodine gargle. Or a patient with recurrent Strep throat. Hospitalized elderly patients, for example, need help keeping pathogens out of their mouths. For these patients, dental hygiene like brushing and flossing, antibiotic mouthwashes, antibiotic gargles, or antibiotic wipes can help keep them safe from dangerous respiratory infections or pneumonia.4

Whitening teeth or freshening breath are not good reasons to kill friendly bacteria. Breath fresheners do not have to kill bacteria to be effective. Teeth whiteners should be used on teeth only. Gargles or mouthwashes to treat gum disease bacteria or bleeding gums should be used under the supervision of a biological dentist, functional dentist, or integrative and functional medicine practitioner.

When a gargle solution is needed (or a mouthwash), it is ideal to choose one that does the minimum lasting damage to the oral microbiome in the first place. Using salt water, plant compounds, or essential oils to gargle may pose less of a risk to the microbiome. Using 1% iodine or 1% hydrogen peroxide is kinder to the good bacteria than using higher concentrations of these gargles. Costs and benefits can be weighed before starting antimicrobial gargles in the mouth. For instance, does the risk of severe COVID infection in this person outweigh the benefit of keeping their oral microbiome intact?

Rebuild the Oral Microbiome after Antiseptic Gargles

When situations arise that demand a gargle solution to “disinfect” the throat, you can take steps to rebuild the oral microbiome afterward.

First, if your practitioner advised you to take an antimicrobial gargle or mouthwash, confirm with him or her that you are “in the clear” and that your risk of infection has passed.

Even while you are taking an antiseptic gargle, you can rebuild your oral microbiome with a whole foods diet. Bacteria feed on healthy components of the diet, such as plant foods, colorful berries, vegetables, and high-fiber foods. Use dental probiotics and/or a probiotic mouthwash like the one from Riven. Feed good bacteria with oral prebiotics and make your mouth a healthy place for bacteria by using non-toxic oral hygiene products.

Build the immune system in your mouth (secretory immunoglobulin A, sIgA) by taking supplements containing colostrum or immunoglobulins. IgA is the protein that protects the mouth lining from pathogens, toxins, and allergens. Fortify your mouth lining. Avoid allergenic foods or those that may promote leaky mouth, such as gluten.

What to Gargle with and How it Affects the Oral Microbiome

Let’s take a look at each of the different gargling solutions you have to choose from: salt water, chlorhexidine, hydrogen peroxide, iodine, essential oils, probiotics, and xylitol. We will review what the evidence says about how they affect bacteria in the mouth.

Do Salt Water Rinses Kill Bacteria?

A salt water gargle solution can be used to gently shift the oral microbiome. It can kill bad bacteria (and good ones, too), but it isn’t extremely effective at killing. Salt water has a great history for wound healing, oral mucosa, and being a generally healthy mouth rinse. It is a gentle agent that targets bacterial cells but spares human cells. Salt water alkalizes the mouth, making it less hospitable to bacterial growth. It has been noted to accelerate healing after surgery and reduce bacterial biofilms and plaque in children.10

Studies suggest that salt water rinses can decrease dental plaque (or kill mouth bacteria), but not consistently.10 In a small study of 13-year-old teenagers, a salt water oral rinse of 10 mL once daily in the morning reduced plaque buildup comparable to 0.2% chlorhexidine mouthwash. The saltwater rinse was added to a regular routine of brushing twice daily over five days. While both reduced plaque buildup and reduced A. actinomycetemcomitans, the chlorhexidine solution was better at killing Lactobacillus acidophillus, Streptococcus mutans, and P. gingivalis (as measured by microbial count).11

When people who had chronic periodontitis and a recent deep cleaning used a salt water rinse, it reduced gingivitis to the same extent as rinsing with 0.12% chlorhexidine solution and was better at preventing plaque buildup.  It also showed an anti-inflammatory effect and was recommended to promote the healing process after surgery.12  They rinsed with salt water one minute, twice daily, about 30 minutes after brushing for 12 weeks. A salt water rinse using H2Ocean based Arctic Ocean mouth rinse significantly reduced plaque accumulation and suppressed inflammation in 30 adult males with gingivitis in conjunction with routine dental hygiene.3 Even gargling with tap water will reduce bacteria in the mouth for one hour.2

Chlorhexidine

Conventional antiseptic mouthwashes contain chlorhexidine, an antimicrobial which lowers the bacteria, spores, and fungi in your mouth. Applied to the mouth lining, 0.12% chlorhexidine reduces ventilator-associated pneumonia.2 Chlorhexidine mouth rinse reduced bacteria on the tongue by 81-90% and reduced bacteria in the saliva by 89-95% (culture study).13

In a small study, a mouthwash of 0.0025% chlorhexidine seemed to reduce friendly bacteria, but not their health benefits. However, authors speculated that regular use of chlorhexidine even at this low concentration could significantly decrease levels of certain health-promoting bacteria.14

Chlorhexidine can stain teeth, cause a change in taste, and increase tartar. There are risks of anaphylactic shock, so chlorhexidine mouthwash is unapproved for use in Japanese hospitals even to prevent ventilator-associated pneumonia.2

Hydrogen Peroxide Gargle

A 1% hydrogen peroxide mixture for gargling is appropriate for fighting off high-risk colds or flus. The good bacteria will probably be impacted. Use higher concentrations only with supervision of a biological or functional dentist for oral dysbiosis (cavities, root canals, mouth or tooth infections). Rebuild the oral microbiome afterwards.

A one percent (1%) hydrogen peroxide solution is thought to be healthy and safe for the oral mucosa, lining of the mouth, and it effectively kills viruses. It has been recommended for prophylaxis against COVID by healthcare practitioners, and in countries where medical resources are limited.10

Does hydrogen peroxide kill good mouth bacteria?

Likely it does.

Hydrogen peroxide isn’t the greatest thing for your healthy oral microbiome. It’s a killer. The higher the concentration of hydrogen peroxide, the more likely that your good bacteria in the mouth will take a hit. Hydrogen peroxide can get into bacterial cells and damage their energy production machinery, harming DNA structure, and killing them.15 It a potent and biologically active substance. It causes oxidative damage to lipids, proteins, and nucleic acids.16

Using hydrogen peroxide can throw your oral microbiome out of balance, causing a condition known as black hairy tongue. Harmless, but annoying, it can give the tongue a furry appearance.

Hydrogen peroxide mouthwashes or gargles can cause temporary irritation in some people, especially if they have mouth ulcers. It can cause serious stomach upset, vomiting, or throat irritation if even a small amount is swallowed. 1.5% hydrogen peroxide is generally well-tolerated without any irritation to the gums or mouth lining. Three percent hydrogen peroxide mouth rinse is safely used in dentistry for debriding, or thoroughly removing plaque and tartar from, the mouth. It only occasionally causes irritation.

Hydrogen peroxide isn’t always friendly to your teeth, either. That’s why tooth whitening treatments can cause tooth sensitivity. Peroxide can deplete minerals from your teeth and make your enamel more rough.15 Dr. Steven Lin, author of The Dental Diet, discourages people from using hydrogen peroxide mouthwash for these reasons.

While hydrogen peroxide solutions of 3%, 6 %, and even higher can be tolerated well by some people, they are best used with the oversight of a dentist.17 Levels this high are very likely to kill many good bacteria, too. If appropriate, make sure to rebuild the oral microbiome for 3-6 months after.

If you want to read more on hydrogen peroxide in the mouth, check out my blog, “The Best Teeth Whiteners for the Oral Microbiome.

Photo by Polina Tankilevitch

Iodine Gargle

 

Iodine recently rose to worldwide fame for its ability to prevent transmission of COVID at pennies per dose. Iodine gargles are potent killers. Gargling polyvinylpyrrolidone-iodine (PVP-1), or iodine, reduces colds and flus. It kills viruses and bacteria activity in cell studies. It works against influenza virus A subtype H1N1, SARS-CoV, MERS CoV, and non-enveloped human rotavirus strain. An iodine mouthwash/gargle of 0.5% povidone-iodine for 30 seconds made SARS-CoV-2 viruses non-infective.18

When gargling it before surgery, PVP-I can reduce the number of microorganisms and bacteria in the upper respiratory tract. After rinsing with a 1:50 dilution of povidone-iodine, salivary bacteria were reduced down to 1%.19

Povidone-iodine applied to the mouth lining of mechanical ventilation patients reduced bacterial growth for at least 3 hours and did not disturb the oral microbiota balance, or promote resistant pathogens or fungi (real time PCR). Authors recommended it as a simple and safe preventative for ventilator-associated pneumonia and a better alternative to 0.12% chlorhexidine.2 A mouthwash of 0.35% povidone-iodine did not harm friendly bacteria or their health benefits in one small study.14

A 0.5% Betadine® gargle is available over the counter as a sore throat gargle.

In situations high risk for bacterial or viral infection, use iodine. The good bacteria are likely to be suppressed, so use it temporarily and rebuild the microbiome afterward.

Another reason to only use iodine temporarily is because regular gargling with PVP-I can cause hypothyroidism, although it will stop after gargling is discontinued. Povidone-iodine can be toxic to the oral lining. It can cause cell death in animal studies.4 On the other hand, it is commonly used before closing wounds in surgery. Prolonged use may stain teeth over time.2

Gargling with Essential Oils

Many companies are using essential oils in their natural dental health products such as toothpastes, mouthwashes, and more. These secondary plant products evolved in order to protect and defend plants, so it’s not surprising that they have antibacterial, antifungal, and antiviral activity. A detailed Table of antimicrobial mechanisms of essential oil mouthwash ingredients can be found earlier in this blog.4

Many research studies have looked at herbal extracts for decreasing cavity-causing bacteria, lowering plaque, and stopping gingivitis.20,21 Essential oils have added benefits for the mouth lining. They may be anti-inflammatory or antioxidants, generally helping to calm down disease processes and heal damaged tissues in the mouth.

The jury is not out as to the extent of harm essential oils pose to the good bacteria.

Popular mouthwashes such as Listerine Cool Mint Mouthwash or CVS Health Antiseptic Green Mint Mouthwash contain eucalyptol 0.092%, menthol 0.042%, methyl salicylate 0.060%, and thymol 0.064% essential oils, dissolved in up to 25% ethanol.14 They can reduce plaque and bleeding gums, which means that they decrease the numbers of bacteria in the mouth. They reduce gingivitis comparable to flossing and they offer additional benefits to the gums when added to a regular routine of brushing and flossing.22,23

Essential oil mouthwashes like Listerine can kill the microbiome in quick time. After 30 seconds using 20 mL of Listerine mouthwash, all anaerobic bacteria were killed by 99%.19 It completely killed microorganisms in 10 to 30 seconds including methicillin-resistant Staphylococcus aureus, Streptococcus pyogenes, Helicobacter pylori, Candida albicans, Streptococcus mutans, Actinomyces viscosus, Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans. It also weakly killed human immunodeficiency viruses (HIV).19 No good bacteria were measured in this study but judging from how well it killed bad bacteria (listed above), it is highly likely it killed good bugs, too.

However, the research findings aren’t consistent. One study showed that Listerine for three months improved gingivitis, pocket depth, and reduced bleeding gums, but did not kill any pathogens.24 Listerine mouthwash spared friendly bacteria in one small study.14

Dentalcidin Toothpaste from Biocidin Botanicals is another antimicrobial formula with a variety of plant extracts and oils.

Probiotic Gargles

 

Probiotic gargles may offer a good alternative to antiseptic gargles, judging from the impressive number of positive studies on probiotic mouthwashes. Probiotics are an interesting option for oral health because the mechanism of action is to use good bacteria to crowd out bad bacteria. No killing of good bacteria is necessary. This is certainly worth trying if you have oral dysbiosis or if you like using a mouthwash or gargle in your daily routine. This way you can build your good bacteria instead of destroying them. Riven has a zero-alcohol probiotic mouthwash with a pleasant, fresh minty flavor.

A probiotic mouthwash was found to work equally as well as chlorhexidine 0.12% or 0.05% sodium fluoride mouth rinse for decreasing Streptococcus mutans in children (measured by colony counts).25 Also, probiotic mouthwash worked similarly to chlorhexidine to remove plaque, improve gum health, and increase oral health indices.26 Levels of the gum-disease causing “bad bacteria” Porphyromonas gingivalis were decreased with a probiotic mouthwash more so than a fluoride mouthwash (RT-PCR).27 And in a randomized clinical trial, a probiotic mouthwash was considered an effective solution for removing plaque when compared to Colgate fluoride mouthwash. Its benefits in reducing plaque were more pronounced after one month of use.28

Xylitol Gargle

Xylitol is a safe, naturally occurring sugar alcohol found in plants such as in the Finnish birch tree. It has been recommended as a mouth rinse ingredient with similar efficacy to chlorhexidine, but without the long-term side effects. It was recommended for both children and the elderly.29  It has also been used in combination with antimicrobials for a better oral health effect.10

Xylitol is an anti-cavity agent, suppressing the growth of the bacteria implicated in cavities, Streptococcus mutans. While it reduces S. mutans, it doesn’t otherwise harm the normal oral bacteria.30 It is not an antiseptic or antimicrobial so it shouldn’t harm good bacteria. Xylitol starves out Candida species in the mouth and makes it harder for Candida to bind to the mouth lining, which makes it a good option for oral thrush. Xylitol isn’t usually metabolized by lactobacillus bacteria, which helps to keep their numbers under control as well.31

 

Recommendations for Gargling Solutions

Depending on your oral health, you might need a different type of gargling product. Are you healthy? Are you having a mild sore throat or a serious risk of infection? At the end of this blog, you’ll find a recipe for how much salt to use in a salt water gargle and the ratios needed to make a 1% hydrogen peroxide gargle at home, as well as 1% iodine. You can gargle 30 – 60 seconds4 two to three times a day.

For a generally healthy mouth, gargle with:

  • Water
  • Salt water
  • Probiotics
  • Xylitol

For sore throat, mild oral dysbiosis, or preventing respiratory infections for temporary use:

  • 1% Hydrogen peroxide solution
  • 1% Iodine
  • Listerine
  • If you have a confirmed SARS-CoV-2 infection, talk with your functional medicine provider about gargling with a 1% hydrogen peroxide or 1% povidone-iodine solution.
  • Use lower concentrations, when possible, to protect good bacteria.
  • Use them temporarily.

For severe throat dysbiosis or in vulnerable populations who cannot carry out proper oral hygiene (the elderly or hospitalized):

  • 1.5 to 3% hydrogen peroxide or higher
  • 1:50 dilution of povidone-iodine
  • Use them under dental or medical supervision.
  • Use them temporarily for preventing serious respiratory illness risks.

Rebuild the mouth bacteria after using antiseptic gargles or mouthwashes.

Other steps for throat and oral health

  • Build the immune system with colostrum or immunoglobulin supplements.
  • Avoid allergenic foods and gluten.
  • Brush twice a day.
  • Floss every day.
  • Stay on top of your dental health visits or periodontist appointments.
  • Test your oral microbiome to look for dysbiosis.
  • Work with an integrative or functional medicine practitioner to uncover other root causes of bad breath, gingivitis, or gum disease.

Photo by Anna Shvets

Recipe for Salt Water Gargle:

  1. Mix one cup of boiling water with ½ to ¾ teaspoon of salt. Stir so that water is white and cloudy.
  2. Let it cool off until it is warm, about 20 minutes.
  3. Swish this salt water mixture around in your mouth and gargle for about 60 seconds.
  4. Spit the solution out after gargling.

Recipe for 1% Hydrogen Peroxide Gargle:

  1. Start with a 3% concentration of hydrogen peroxide. This is the strength you’ll find in a brown bottle at most drug stores. Next, combine one part hydrogen peroxide with two parts water. Your final mix will have a concentration of 1% hydrogen peroxide.
  2. Tilt your head back and take a small mouthful of your hydrogen peroxide and water mix. Gargle and swish the mixture around in your mouth for 60 seconds.
  3. Spit the solution out after gargling. Don’t try to gargle the mixture for more than 90 seconds. Never swallow it.

Recipe for 1% Iodine Gargle:

  1. Dilute 10% Povidone-Iodine by one-tenth so that it is 1% strength.
  2. To do this, add 10ml (2 tsp) of the 10% solution to 100ml of water. This will make the solution diluted enough to use as a mouth rinse or gargle.
  3. Gargle at least 2 tbsp of the diluted solution for at least 30 seconds. DO NOT SWALLOW THIS RINSE.

 

Think Twice Before You Gargle

Gargling can help with a sore throat and even ward off dangerous lung infections. However, use caution because antiseptic gargles and mouthwashes can kill good bacteria, too. Those with generally healthy mouths should not take microbiome-killing gargles on a regular basis. Gargling with probiotics, water, salt water, xylitol, or oil pulling can help spare the good bacteria while gently shifting the bad. Those with infections in the mouth or those that are at high risk may benefit from antiseptic gargles for a short time while under the supervision of a biological or functional dentist. When antiseptic gargles are necessary, rebuild good bacteria in the mouth with a fiber-rich diet, prebiotics, and probiotics.

 

 

Riven is a company that specializes in creating oral care products that harness the power of probiotics to support the health of the oral microbiome. Their flagship offering is the Riven Rinse, a mouthwash that combines clinically supported ingredients, antioxidants and probiotics/prebiotics to help achieve a cleaner and healthier mouth.

 

References

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  2. Tsuda S, Soutome S, Hayashida S, Funahara M, Yanamoto S, Umeda M. Topical povidone iodine inhibits bacterial growth in the oral cavity of patients on mechanical ventilation: a randomized controlled study. BMC Oral Health. Feb 24 2020;20(1):62. doi:10.1186/s12903-020-1043-7
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Cass Nelson-Dooley, M.S.
Cass Nelson-Dooley, M.S.

Cass Nelson-Dooley, MS, is a researcher, author, educator, and laboratory consultant. She studied medicinal plants in the rain forests of Panama as a Fulbright Scholar and then launched a career in science and natural medicine. Early on, she studied ethnobotany, ethnopharmacology, and drug discovery at the University of Georgia and AptoTec, Inc. She joined innovators at Metametrix Clinical Laboratory as a medical education consultant helping clinicians use integrative and functional laboratory results in clinical practice. She owns Health First Consulting, LLC, a medical communications company with the mission to improve human health using the written word. Ms. Nelson-Dooley is an oral microbiome expert and author of Heal Your Oral Microbiome. She was a contributing author in Laboratory Evaluations for Integrative and Functional Medicine and Case Studies in Integrative and Functional Medicine. She has published case studies, book chapters, and journal articles about the oral microbiome, natural medicine, nutrition, laboratory testing, obesity, and osteoporosis.