In this article, originally published in AromaCulture Magazine in July, I discuss herbal and dietary support for CF children and adults. I discuss digestion, respiratory disease, liver support, and modulation of CFTR sodium chloride channels by natural means.
Cystic fibrosis is an autosomal recessive genetic disease that leads to the malfunctioning of several organ systems but most especially impacts the lungs, sinuses, and digestion. It is the most common autosomal recessive genetic disorder (meaning that each parent must be a carrier of the genetic mutation) in people of Western European decent. There are approximately 30,000 people living with cystic fibrosis (CF) in the United States, and more than 70,000 people worldwide.
More than 75% of people with CF are diagnosed by the age of two[i]. It is a degenerative disease and the median life expectancy in the United States is 37 years old[ii]. In the last several decades, extensive research and new drug interventions have allowed what used to be considered a childhood disease to transition into a manageable illness where individuals may live well into adulthood.
The primary pathophysiological feature of CF is the mutation and malfunction of the sodium-chloride channels on the cell membranes of epithelial tissues, which leads to a thick, sticky mucus in the lumina of the bronchi, bronchioles, intestines, pancreatic ducts, as well as the sinuses and other epithelial tissues. Depending on the genetic mutations or phenotype of the individual, other organs may be involved leading to chronic liver disease, CF-related diabetes (CFRD, a combination of both insulin-insufficiency and insulin resistance), immunodeficiency, osteoporosis, and other complications. Thick mucus in the respiratory system leads to plugged airways, bronchiole scarification, and vulnerability to bacterial and fungal infections. The targets of most conventional therapies developed for CF are to thin the mucus in the lungs, help the individual cough it out, supplementation with pancreatic enzymes to aid with digestion, and frequent use of antibiotics to treat recurring bacterial lung and sinus infections.
Although almost all CF people develop both digestive and respiratory disease, individuals tend towards having difficulty with one system more than the other, especially as children. Like most chronic diseases, CF’s presentation is unique to every individual, thus personalized medicine is the most effective way to treat this disease. Western herbalism and other traditional healing systems such as Traditional Chinese Medicine and Ayurveda are inherently personalized, therefore integration of these modalities can be very beneficial to the clinical outcomes of the intervention. Complementary medicine can help address symptoms and root causes of disease where conventional medicine fails to do so, and also can help reduce the negative side effects of some conventional medical treatments. As a clinical herbalist and person with CF, I have helped myself and other CFers improve overall health quality and reduce symptomatology with use of herbs, diet, and lifestyle changes, some of which I will describe below.
Improving Health Outcomes During Childhood: Diet and Digestion
Once the diagnosis has been made, the primary focus of conventional treatment for children with CF is digestive: getting in enough calories to maintain weight gain and growth, provide supplemental pancreatic enzymes when the pancreas cannot produce its own (90% of people with CF have pancreatic insufficiency[iii]) and address nutrient deficiencies with supplementation. A secondary focus is on prevention and treatment of bacterial lung infections.
The early childhood years after weaning can be some of the most challenging in terms of finding the right brand and dose of pancreatic enzymes to ensure proper fat digestion (steatorrhea is common in CF) and also finding solutions to the numerous digestive symptoms that can arise including gastric reflux, stomach aches, cramping, diarrhea, constipation, and gas. Herbal and dietary interventions can significantly help a child’s digestion and help improve weight gain, growth, immunity, and overall vitality.
Considering Conventional Medications for Digestion
Most CFers will need take supplemental pancreatic enzymes, and finding the right brand is an important first step. Many pancreatic enzymes brands on the market contain phthalates and contain sodium bicarbonate, both of which can have negative side effects. Two enzyme brands without phthalates or sodium bicarbonate are Pancreaze (which I use) or Viokace. Phthalates are known to cause liver damage in animal studies, and I have spoken with several parents of CF children whose elevated liver enzymes (AST and ALT) dropped back down to normal after switching to a brand of enzymes not containing phthalates. I will discuss this issue in greater detail further on. There are some over-the-counter supplemental pancreatic enzymes available, but they are generally not enteric-coated (which is required) and they do not contain high enough levels of lipase per capsule for the needs of a CF person.
Secondly, it is now unfortunately standard protocol in many CF specialty clinics to prescribe proton-pump inhibitors (PPIs) or other antacids to CFers to address generalized digestive complaints or to make their pancreatic enzymes work better to reduce steatorrhea. PPIs are overused and inappropriately used even in the general American population to address gastric reflux by reducing the stomach’s ability to produce hydrochloric acid, thus lowering gastric acidity. In most cases reflux is caused by low, not high stomach acid because adequate acidity in the stomach is what triggers the lower esophageal sphincter (LES) between the stomach and esophagus to close, preventing acid reflux[iv] [v] [vi] [vii]. Although PPIs are not FDA approved for long term use, they are frequently prescribed that way and unfortunately this makes reflux worse in most cases, leading to dependence on higher and higher doses. There is also the issue that inadequate sodium bicarbonate production in the pancreases of some people with CF caused increased acidity in the duodenum[viii], leading to the inactivation of supplemental pancreatic enzymes that need alkaline environments in order to activate.
Herbal Digestive Support
Fortunately, there are herbal solutions to digestive problems like reflux as well as to the possible problem of inadequate bicarbonate production that may allow CFers to avoid PPIs and their negative side effects (including nutrient deficiency, bone loss, enteric infection, asthma, etc.[ix]). The use of bitter herbs before meals is an effective tool for improving overall digestion. Bitter tastants cause the release of the hormone cholecystokinin, which stimulates gastric secretions, bile release from the liver and gallbladder, insulin production, pancreatic enzyme secretion, and eventually leads to bicarbonate release from the pancreas[x]. Tinctures, teas, or honey-pastilles of bitter herbs have been traditionally used in Europe for centuries to stimulate the digestion before meals, to settle upset stomachs, and as overall digestive tonics. The use of bitter tinctures (both alcohol based and apple cider vinegar based) before meals in people with CF, adults and children, often results in improved fat absorption, decreased digestive discomfort after meals, and improved transit times. Improving transit time both increases appetite and allows for more frequent meals, thus increasing daily calorie intake. Some bitter herbs commonly used are dandelion root, gentian root, artichoke leaf, and burdock root formulated with small amounts of ginger and something to sweeten it, such as licorice or stevia (for picky eaters, honey may be used to sweeten the tinctures). It is important to remember that the effect that bitters have on the body is triggered by a taste reflex, so the person must be able to taste the bitterness in order for the benefits of these herbs to be conferred. A typical dose of a bitters tincture is 1-3mL (depending on the weight of the individual) on the tongue or in a little water, about 5-10 minutes before meals. Bitters can also be used as needed during bouts of reflux, and can do well paired with soothing, mucilaginous herbs such as licorice or marshmallow root. Reflux can also be improved by drinking a tablespoon of apple cider vinegar in a cup of water when symptoms arise or taken before meals as prevention.
Stomach aches, cramping, bloating, diarrhea, and intestinal pain are all common symptoms that children and adults with CF experience on a regular basis. Significant digestive complaints, especially diarrhea, can reduce absorption of nutrition and calories from food, therefore a primary focus of herbal intervention should be on calming digestive symptoms to improve nutrient absorption and weight gain. Teas or tinctures of peppermint leaf, ginger root, meadowsweet leaf and flower, chamomile flower, plantain leaf, licorice root, ginger root, and others can be very soothing to the gastrointestinal tract by helping to reduce inflammation and relax digestive muscles to dispel gas. Meadowsweet (Filipendula ulmaria) in particular is an excellent herb for reducing pain and inflammation in the intestinal tract and tastes great in tea. It is slightly demulcent and contains methylsalicylates[xi], which are strongly antioxidant and inhibit inflammatory prostaglandin formation. Meadowsweet and the above herbs are food-like and safe to drink several times per day.
Gastroparesis (delayed gastric emptying) is another common ailment in CF children and often has to do with overall poor digestive secretions partly due to a diet without bitter plants, as is common in the West. Adding regular use of bitter herbs or foods can help, as well as capsules or teas of ginger root. Ginger (Zingiber officiale) is used as a warming digestive and circulatory stimulant, excellent for nausea, gas, bloating, as well as arthritis and many other uses. Because ginger is so spicy, small doses are best. I have found that 1-3g of encapsulated ginger taken after a meal can help speed up sluggish digestion and hasten gastric emptying, especially when meals have been too large or too complex. In older children and adults, small doses of kava tincture (Piper methysticum) can be used in a similar way to hasten gastric emptying.
A very important part of the protocol for people with CF is obtaining enough high-fat, high-calorie foods that help maintain weight and energy levels. Weight loss and nutritional deficiencies, especially of fat-soluble vitamins, are very common and the conventional solution is often to allow the child or adult to eat freely with no dietary restrictions, including junk food, sodas, and sugar-laden “nutritional supplements” like Ensure. Children with CF are often picky eaters and have poor appetites, so parents are sometimes desperate to find anything that the child will eat, making junk food a common default. However, people with CF are not exempt from the laws of human nutrition – in fact, our bodies are more sensitive to poor food choices than people without CF because our background levels of inflammation are many times the norm[xii]. Avoiding inflammatory foods while optimizing calories and nutrient density should be the goal of a healthy CF diet. Furthermore, there is a very strong connection between the level of irritation and mucus-production in the digestive tract and the amount of mucus produced in the respiratory system. The lungs, sinuses, and gastrointestinal tract are connected via vagal enervation, and irritation in one system can lead to reflexive irritation in the other. Thus, avoiding irritating and inflammatory foods can make a big difference in reducing baseline mucus production in the lungs.
To this end, people with CF often do best when removing sugar and refined sweeteners, gluten and refined carbohydrates, dairy (with some exceptions), and industrial seed oils (such as from canola, sunflower, corn, refined/toasted sesame, low-quality non-organic olive oil, or generally “vegetable oil”). The focus of the diet should be on nutrient-dense, antioxidant-rich foods including organic darkly colored vegetables (especially leafy greens), grass-fed and pasture-raised beef and pork, wild-caught fish, pasture-raised eggs, fibrous root vegetables, fruits (especially berries, apples, and avocados), nuts and seeds, probiotic fermented foods (sauerkraut, miso, kombucha, etc.), and animal fats. Grass-fed dairy or gluten-free whole grains may be included if they are well tolerated. Often an Ancestral or Paleolithic diet serves as a good template, which can be modified to meet the individual’s needs and to avoid specific food intolerances. Poor digestion in CF is often the result of a combination of functional disregulation and improper food choices that lead to further exacerbation of baseline digestive inflammation. People with CF (myself included) can experience significant personal improvement of digestive (and respiratory) symptoms by cleaning up the diet.
Parents of children with CF will often have to resist pressure from their doctors who abhor dietary restrictions and like to push sugar-laden “nutrition shakes” on their patients. However, there are now excellent high-nutrient, whole food, sugar-free nutritional powders and shakes available at most grocery and health food stores that are much healthier and just as effective. Some good products include Garden of Life’s meal replacement powders and Vega’s all-in-one plant protein powders, however these are generally low in fat so it’s a good idea to add fat to these shakes from canned coconut milk, flax seed oil, avocado oil, or other high-quality oil. Since fat digestion is a concern with CFers, children and adults who are experiencing steatorrhea or are having trouble gaining weight should consider adding lecithin powder or liquid to fatty foods or shakes/smoothies to improve fat emulsification for better absorption in the small intestine. Lecithin can be sourced from eggs, soy, or sunflower seeds.
For the majority of people with CF, frequent use of antibiotics for sinus and lung infections is an unavoidable necessity. Improving the diet and digestion may significantly improve the vitality and immune status so that the individual is more resilient in fighting off infections. However, when infections do take hold, herbs can play a complementary role to conventional therapy.
A major part of respiratory support is maximizing immune resilience and encouraging mucus thinning and expectoration. Astragalus propinquus, a popular root from Chinese Medicine, is an excellent immune-stimulating and immune-modulating herb. Astragalus has been shown to modulate immunity by activating regulatory T-cells[xiii] and stimulates overall innate immunity[xiv]. In Chinese Medicine it is used to disperse phlegm and as a respiratory tonic for weak lungs[xv]. I think of astragalus as one of the primary herbal allies of any person with CF, as it is very safe for all ages and has no known drug interactions. It can be taken as a tincture, in powder or capsules, or as a long-simmered tea called a decoction. Fortunately, it tastes sweet and mild, making it palatable even for children. Another excellent expectorant, adaptogen, and mucous-membrane tonic is licorice (Glycyrrhiza glabra). It can be taken in tincture, tea, powder, or capsule. It is contraindicated in people with high blood pressure. For expectoration, elecampane (Inula helenium) is an herb from Western herbalism, use traditionally as an expectorant, warming bitter, and antimicrobial for the respiratory and digestive systems. Used in small doses as a tonic or in larger doses to combat acute infections, it is a broad spectrum antimicrobial and is used to thin and encourage the clearance of mucus from the lungs[xvi].
The most common infections and colonizations in the lungs of CFers are by Pseudomonas aeruginosa and Staphylococcus aureus (including its common drug-resistant strain, Methicillin-resistance S. aureus, MRSA). Because whole-herb preparations contain hundreds of different phytochemical compounds, the risk of bacterial resistance to herbs is much lower than for pharmaceutical antibiotics, so herbs can play a helpful role in combating drug-resistant bacteria. In addition, many herbs can make antibiotics work better by inhibiting bacterial efflux pumps[xvii], and breaking through bacterial biofilms (e.g. thyme, rosemary, berberine containing plants like barberry root or Oregon grape root, etc.). Fresh garlic is one of the most powerful herbs for the respiratory tract and is strongly antibacterial, antifungal, and antiviral[xviii] [xix]. Freshly-chopped raw garlic provides the most antimicrobial activity. Tinctures of thyme (Thymus vulgaris), elecampane, osha (Ligusticum porteri), Cryptolepis sanguinolenta, and others are some of our strongest antibacterial herbs and can be helpful against both gram-positive and gram-negative bacteria, including drug-resistant ones[xx].
An area that I have a good amount of personal experience with is the use of antimicrobial essential oils both for inhalation and rectal suppositories. Certain essential oils have antibacterial activities equal to or stronger than some of the most potent antibiotics currently in existence, especially against bacterial biofilms. These include cinnamon, clove, thyme (chemotype thymol), and lemongrass (Cymbopogon spp.)[xxi] [xxii] [xxiii] [xxiv] [xxv], however these oils can be very harsh and irritating to the mucous membranes so they need to be used with caution or with the advice of an herbalist or certified aromatherapist. For small children, a good place to start is with inhalation of gentler oils such as lavender, tea tree, and peppermint essential oils via aromatherapy diffuser kept close to the head, either when sitting down resting or when sleeping. Lavender and eucalyptus species are anti-inflammatory[xxvi] [xxvii], and both tea tree and peppermint essential oils have shown activity against gram-negative bacteria including Pseudomonas aeruginosa and their biofilms[xxviii] [xxix]. Children ages 8 and older may begin to experiment with small amounts (1-3 drops) of simples or combinations of these three oils diluted in about 5mL sterile saline and inhaled through a nebulizer. Nebulizing essential oils can be done during acute infections or for several weeks at a time on an ongoing basis, taking 2-week breaks in between, in attempts to clear a long-term bacterial colonization. In a 10-year-old CF client, regular nebulization of this kind made the Pseudomonas in his sputum cultures more sensitive to a wider range of antibiotics, and after two years he had his first bacteria-free culture. As a reminder, it is very important to source undiluted, pure essential oils for inhalation from a reputable company that sources exclusively from organic or un-sprayed plants. The company should be able to provide detailed batch records, GC/MS test results, and information on sources and chemotyping.
Adolescents and adults can begin to experiment with nebulizing stronger essential oils that combat a larger range of bacteria. I have personally had good results in shifting the bacterial load and antibiotic sensitivity of my sputum cultures through nebulizing essential oils such as tea tree, thyme (Benchmark Thyme, chemotype linalool), frankincense, lemongrass (in very small amounts and well-diluted), Eucalyptus globulus, and Eucalyptus citriodora[xxx] [xxxi]. Rectal suppositories may be an even more effective way to use essential oils for respiratory infections because the oils are quickly and easily absorbed into the blood stream via the highly vascularized tissue in the rectum, circulating the compounds throughout the body first before being metabolized by the liver and kidneys[xxxii]. It is also more tolerable to take in larger doses of stronger herbs via the rectum than via inhalation, including thyme (ct. thymol), lemongrass, rosemary (ct. camphor), oregano, and cinnamon. Cinnamon, thyme, and lemongrass are oils showing some of the strongest activity against MRSA[xxxiii] [xxxiv]. When inhaling essential oils by nebulizer or using oils via rectal suppository it is best to have guidance from an aromatherapist or herbalist, as there is risk of improper use causing mucosal irritation or damage. If there is significant airway irritation (other than coughing, which is a normal reaction) or bronchospasm, burning or severe discomfort of the throat or mouth (or rectum, in the case of suppositories), symptoms of allergic reaction, kidney pain, or difficulty with urination, stop using essential oils immediately and seek medical attention.
Children and adults with CF can develop chronic liver disease with elevated liver enzymes indicating liver inflammation or steatohepatitis. Liver disease in CF children has been linked to increased intestinal permeability and intestinal dysbiosis[xxxv], meaning that the diet and gut inflammation may be important points of intervention. In addition, there are several brands of enteric-coated pancreatic enzymes that are available in the U.S., and most of them contain phthalates[xxxvi], a class of chemical plasticizers known to induce liver oxidation and damage, reduce hepatic glutathione, and disrupt liver metabolism[xxxvii]. These are symptoms that do occur in some children that take phthalate-containing enzymes. Phthalates are also endocrine disruptors, and have been shown to disregulate serum insulin, blood glucose, liver glycogen, thyroid hormones, and cortisol[xxxviii]. The most commonly prescribed enzyme brand in the U.S. is Creon, which contains hypromellose phthalate. The two enzyme brands that do not contain phthalates are Pancreaze and Viokace. I personally use Pancreaze.
If liver inflammation is present, indicated by elevated liver enzymes (i.e. AST, ALT), high serum bilirubin and/or albumin, common conventional treatment is prescription of ursodiol (ox bile). There are several herbs that have been shown to reduce liver inflammation, most especially milk thistle. Several studies have shown 80% silymarin extracts from milk thistle to be effective at reducing liver inflammation in humans[xxxix]. Studies and clinical experience have shown that effective doses are between 400mg and 1000mg per day, depending on weight and level of liver inflammation, taken in divided doses with meals. Curcuminoid extracts from turmeric root have also been shown to decrease liver inflammation as well as systemic inflammation[xl] [xli]. Turmeric and curcuminoid extracts must be formulated with black pepper and taken with fatty meals in order to optimize bioavailability.
Sodium-Chloride Channel Modulation
A new line of research in the several years has been on both herbal and pharmaceutical agents that correct malfunctioning of the CFTR protein, which is responsible for the thick mucus that leads to many of the problems associated with CF. Several studies have pointed to the additive effects of pairing curcuminoids (from turmeric) with the isoflavone genistein (from soy) for correcting CFTR gating in certain mutations[xlii], and clinical trials in Europe are studying the pairing’s effects on CF patients[xliii]. In the last year, research has led to the development of an herbal supplement now available on the market, called Indeptra, which is designed specifically to help correct CFTR function[xliv]. It has several formulations, each targeting specific CF mutation classes. For example, the Indeptra B formula is suggested for class II mutations including deltaF508 (the most common CF mutation) and contains the following herbal extracts: curcuminoids from turmeric, trans-resveratrol from Japanese knotweed, amentoflavone, quercetin dihydrate, Bioperine from black pepper, silymarin from milk thistle, EGCG from green tea, hawthorn berry and leaf, and forskolin from Coleus forskolii. I take Indeptra B myself (I am homozygous for deltaF508) and two of my CF clients (ages 7 and 10) have experienced improvement in their digestion from this formula.
There are many herbs that can be very effective in helping to reduce symptomatology and target the underlying dysfunctions in CF. I have mentioned a few herbal and dietary interventions that I have used, but there are many more. People with CF often have to take many expensive prescription drugs, often with significant side effects, so minimizing the need for these drugs while optimizing qualitative and quantitative metrics of health through natural supportive therapies is the goal of holistic CF care.
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Mica McDonald (they/he) is a clinical herbalist, nutritionist, ecologist, and writer living in Abenaki territory (Vermont).