Do Eating Fermented Foods Boost Immunity?

admin • October 11, 2020

Fermented foods can ease the symptoms you feel in your gut.


Here's why:

The symptoms you feel in your gut are caused by your unbalanced immune system producing too much inflammation. In order to balance your immunity and reduce inflammation in your gut, it is important to restore balance to the helpful bacteria that live in your gut. Those helpful bacteria come in hundreds of different types and have many functions including helping you digest, unlocking nutrients in foods, and maintaining a healthy immune system. 1 Restoring balance to the huge ecosystem of helpful bacteria in your gut requires eating helpful bacteria. 2,3,4 The best source of those helpful bacteria is from fermented foods such as sauerkraut, yogurt, or kombucha. These foods are such a good source of helpful bacteria because the fermentation process allows for a diverse collection of helpful bacteria to multiply and grow on the foods. When we eat these fermented foods, those helpful bacteria then begin living in our gut where they help maintain a healthy immune system.


Where can I buy Fermented Foods?

The best place to get your fermented foods is from your own home. Eating food that you ferment yourself will ensure that you are getting the largest diversity of helpful bacteria possible.


If you do choose to ferment your own foods, do not can your fermented foods. The canning process kills all the helpful bacteria in your fermented foods.


Fortunately, there are some fermented food products available at the grocery store.


In the grocery store, look for fermented products that are unpasteurized, that use a SCOBY (symbiotic culture of bacteria and yeast) and/or that list many different types of helpful bacteria in the product.


A few examples of these products are provided at the end of this packet. Alternatively, ask your local farmers about any fermented products they may sell.


Fermented Foods at Home vs Mass-Produced Fermentation

Traditionally, foods get fermented when we allow helpful bacteria to break down food in a controlled environment. This fermentation process allows a diverse collection of helpful bacteria to grow on the food. When we eat these foods, those helpful bacteria begin living in our gut where they help us digest foods, unlock nutrients in foods, and maintain a healthy immune system.


The process of industrially producing fermented foods reduces the diversity and number of helpful bacteria in those foods. In this industrialized process, foods are first fermented then heated up to kill all the helpful bacteria in the food (aka pasteurized) and then packaged. These steps are taken to increase shelf life. Sometimes after heating, the foods are injected with a selection of a couple helpful bacteria for health benefits. However, using only a couple of different types of helpful bacteria means those foods have less diversity of helpful bacteria than traditionally fermented foods. This reduction in diversity makes industrially produced fermented foods less effective in restoring balance to the helpful bacteria in your gut and, ultimately, less effective in easing your gut symptoms.


Fermented products at the grocery store that are unpasteurized, that do not use preservatives, that use a SCOBY, and/or that list the many helpful bacteria in the product are more likely to contain a large diversity of helpful bacteria. Even better, foods fermented at home or by your local farmers contain a huge diversity of helpful bacteria.


Food Allergy and Fermentation

In addition to helping maintain a healthy immune system, eating fermented foods can also reduce your risk of eating something that gives you an allergic reaction. When most foods ferment, the part of the food that causes allergic reactions is broken down.5,6 So, you may be allergic to milk or cabbage, but you still may be able to eat yogurt or sauerkraut without experiencing allergic symptoms.

Probiotic Supplements and food options can be found at your local grocery store.


Probiotic supplements contain a selection of a few types of helpful bacteria. While these pills can be useful in certain situations, even the best probiotic supplements only contain a few different types of helpful bacteria while a healthy human gut contains hundreds of types of helpful bacteria. Due to this lack of diversity in probiotic pills, eating fermented foods containing a large diversity of helpful bacteria can be more effective in restoring the balance of helpful bacteria in your gut.


We've assembled a list of ways that can help you identify what to avoid and what to buy.

  • Look for a list of helpful bacteria.
  • If allergic to dairy, try milk kefir alternatives.
  • Look for Kombucha that utilizes SCOBY.
  • Look for foods that are unpasteurized.
  • Check for ingredients you may be allergic to such as wheat proteins.
  • Check that there are no preservatives in the ingredients list.


Examples of Common Fermented Foods

  • Saurekraut
  • Kimchi
  • Sour Pickles
  • Olives
  • Capers
  • Dilly Beans
  • Water Kefir (aka Tibicos)
  • Kombucha
  • Yogurt
  • Milk Kefir
  • Almond Milk Kefir
  • Creme Fraiche
  • Buttermilk
  • Farmstead cheese
  • Miso
  • Tempeh
  • Fish Sauce
  • Soy Sauce
  • Fermented Black Bean


*Sour pickles are different from regular pickles. Regular pickles are made by adding vinegar to the vegetable, also known as pickling. This process does not allow helpful bacteria to grow so eating ‘regular’ pickles, is not helpful in restoring balance to your gut bacteria.

Sour pickles are made by way of fermenting the vegetable in a similar manner to the sauerkraut making process. Almost any vegetable can be made into a sour pickle including cucumbers, carrots, green beans, okra, cauliflower, radishes, peppers, etc.


1 Goto, Yoshiyuki, and Hiroshi Kiyono. “Epithelial Barrier: an Interface for the Cross‐Communication between Gut Flora and Immune System.” Wiley Online Library, John Wiley & Sons, Ltd, 15 Dec. 2011, onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-065X.2011.01078.x. 2 Veiga, Patrick, et al. “Changes of the Human Gut Microbiome Induced by a Fermented Milk Product.” Nature News, Nature Publishing Group, 11 Sept. 2014, www.nature.com/articles/srep06328. 3 Derrien, Muriel, and Johan E.T. van Hylckama Vlieg. “Fate, Activity, and Impact of Ingested Bacteria within the Human Gut Microbiota.” Trends in Microbiology, Elsevier Current Trends, 1 Apr. 2015, www.sciencedirect.com/science/article/pii/S0966842X15000566. 4 Oozeer, Raish, et al. “Survival of Lactobacillus Casei in the Human Digestive Tract after Consumption of Fermented Milk.” Applied and Environmental Microbiology, American Society for Microbiology, 1 Aug. 2006, aem.asm.org/content/72/8/5615.short

El-Ghaish, Shady, et al. “Potential Use of Lactic Acid Bacteria for Reduction of Allergenicity and for Longer Conservation of Fermented Foods.” Trends in Food Science & Technology, Elsevier, 14 May 2011, www.sciencedirect.com/science/article/abs/pii/S0924224411000926. Shi, Jing, et al. “Effects of Fermentation by Lactobacillus Casei on the Antigenicity and Allergenicity of Four Bovine Milk Proteins.” International Dairy Journal, Elsevier, 5 Nov. 2013, www.sciencedirect.com/science/article/abs/pii/S0958694613002616



Alpha-gal syndrome: what the headlines mean for your time outdoors

September 29, 2026
Recent stories about ticks and the illnesses they can cause have brought alpha-gal syndrome into the spotlight. The Associated Press covered the expanding range of the lone star tick and growing recognition of this unusual food allergy in June 2026. A July feature in The New Yorker explored the broader changes helping ticks thrive and the effects on people who spend time outdoors. Those reports raise worthwhile questions, but they do not mean you should give up hiking, gardening, or enjoying East Tennessee. Our message is reassuring: enjoy the outdoors, take sensible precautions, and seek help if symptoms develop. Alpha-gal can be managed, and it can resolve in some people over time. WHAT IS ALPHA-GAL SYNDROME? Alpha-gal is a sugar found in most mammals, including cows, pigs, sheep, and deer. In some people, a tick bite prompts the immune system to make allergy antibodies against it. In the United States, the lone star tick is the main tick associated with this process. Someone who develops alpha-gal syndrome may then react after eating beef, pork, lamb, venison, or other mammalian products. Poultry, fish, and eggs do not contain alpha-gal. Unlike Lyme disease or other bacterial tick-borne illnesses, alpha-gal syndrome is an allergy. Antibiotics such as doxycycline have no established role in preventing it after a bite. HOW WORRIED SHOULD YOU BE? Alpha-gal syndrome remains uncommon overall, but the risk is uneven. It is more relevant in regions with established lone star tick populations, including Tennessee. Not everyone bitten by a tick develops the syndrome, and having detectable alpha-gal antibodies does not necessarily mean someone has a food allergy. Diagnosis requires a compatible clinical history as well as appropriate testing. Fatal reactions appear exceptionally rare, but documented deaths show that the risk is real. Researchers at the University of Virginia reported a confirmed fatal reaction in 2025. There is no reliable national fatality rate, so we should avoid assigning a precise percentage. Severe reactions can occur even though death is unusual. Recognizing symptoms and having an emergency plan make a meaningful difference. WHY SYMPTOMS CAN BE CONFUSING Most food allergies cause symptoms soon after eating. Alpha-gal reactions usually begin several hours later, commonly around 2–6 hours, and sometimes later still. A reaction to dinner can therefore wake someone during the night. Symptoms can include itchy hives, swelling, abdominal cramps, nausea, vomiting, or diarrhea. Some patients have digestive symptoms without a rash. Reactions can also affect breathing or blood pressure. They may not happen after every exposure, which can make the food connection harder to recognize. Repeated unexplained symptoms several hours after mammalian foods deserve evaluation. For trouble breathing, throat swelling, faintness, or a rapidly progressing reaction involving multiple body systems, use prescribed epinephrine immediately and call 911. Antihistamines cannot replace epinephrine for anaphylaxis. DOES A DIAGNOSIS MEAN GIVING UP ALL ANIMAL PRODUCTS? No. Avoiding mammalian meat is the foundation of dietary management, but other restrictions depend on the person. Many patients tolerate dairy. Some need to avoid gelatin or hidden mammalian ingredients such as lard, tallow, broth, or meat casings. Cooking meat does not reliably make it safe. We help patients identify the restrictions that fit their reactions while protecting nutrition and quality of life. Your clinician and pharmacist can also review medications when necessary. Do not stop essential medicines simply because an ingredient might have an animal source. CAN ALPHA-GAL SYNDROME GO AWAY? Yes, it can resolve in some people, especially when further tick bites are avoided. New bites can increase sensitization and prolong or reactivate the allergy. Avoiding trigger foods helps prevent reactions, while preventing additional tick bites gives the immune response a chance to settle. Recovery varies and can take years. It is a possibility, not a promise. The American Gastroenterological Association describes follow-up testing about 6–12 months after diagnosis when a patient avoids further bites. Clinicians use repeat alpha-gal–specific IgE measurements to follow the trend alongside symptoms and exposure history. A falling or negative result alone does not prove that a food is safe. The outcome data offer hope while showing why follow-up matters. In a Mayo Clinic cohort, 22 of 40 patients with follow-up reported complete symptom resolution, but only seven reported successfully returning to a regular diet. Their average time to diet reintroduction was about 20 months. Feeling well while avoiding a trigger is different from tolerating that trigger again. These findings do not predict an individual patient's recovery. If recovery seems likely, your clinician can discuss whether a food challenge or a carefully planned reintroduction is appropriate. When dairy has been restricted, it may be reconsidered before mammalian meat. People with previous systemic reactions need specialist guidance. Do not experiment with meat on your own based on a blood-test number. Oral immunotherapy with milk or meat remains investigational. SIMPLE TICK PRECAUTIONS FOR EVERYDAY LIFE You can lower exposure while continuing to enjoy the outdoors: - Before heading out: use an EPA-registered repellent such as DEET or picaridin according to its label. Wear clothing that covers exposed skin. Treat clothing and gear with 0.5% permethrin or use pretreated items. Permethrin belongs on clothing and gear, not directly on skin. - On a walk: stay near the center of trails and avoid brushing against tall grass or dense vegetation. - After coming indoors: check your body, clothing, children, and gear for ticks. Shower within two hours. Tumble-dry dry clothing on high heat for 10 minutes, with additional time if damp. - If a tick is attached: use fine-tipped tweezers to grasp it close to the skin and pull upward with steady, even pressure. Clean the area afterward. WE’RE HERE TO HELP At Pienkowski MD, Allergy & Asthma Clinic, we help patients connect symptoms with possible triggers, interpret testing, and build a treatment and emergency plan. We can also follow your progress and help determine whether food restrictions can change over time. East Tennessee has too much to enjoy to let headlines make every outdoor outing feel frightening. Take sensible precautions, know what to watch for, and reach out when you need us.  Visit pienkowskimd.com for information about our clinics in Knoxville, Greeneville, Johnson City, Kingsport, and Bristol.

Why You Have Allergies in the Fall

September 14, 2026
Fall brings Big Orange football to East Tennessee, but it can also bring sneezing, congestion, itchy eyes, and fatigue. If your allergies return as summer winds down, ragweed may be a major reason. For some people, the same pollen allergy also helps explain why a bite of melon or banana makes their mouth itch. WHY FALL IS ALLERGY SEASON Ragweed releases highly allergenic, windborne pollen in late summer and fall. When someone with ragweed allergy breathes it in, their immune system recognizes pollen proteins as a threat and releases chemicals, including histamine, that cause allergy symptoms. The season often begins in August and continues into autumn, usually ending with a killing frost. Peak timing varies with location and weather, and warmer regions can have a longer season. Ragweed is a leading fall pollen trigger, although other weeds and outdoor mold can contribute too. WHAT RAGWEED ALLERGY FEELS LIKE Common symptoms include repeated sneezing, a runny or stuffy nose, postnasal drainage, and itching of the nose, throat, or eyes. Eyes may also look red and water frequently. Some patient may even feel excessive fatique. Ragweed can also aggravate asthma, causing coughing, wheezing, or chest tightness. If fall brings more asthma symptoms or increased use of your rescue inhaler, your treatment plan deserves a review. Your symptom history, together with targeted skin testing for allergen-specific IgE when appropriate, can help identify the cause. WHY MELON OR BANANA CAN MAKE YOUR MOUTH ITCH Some proteins in raw foods resemble proteins in pollen. In certain people with ragweed allergy, the immune system reacts to these similar food proteins as well. This is called “pollen-food allergy syndrome,” also known as “oral allergy syndrome.” The classic ragweed-associated foods include: - Melons: watermelon, cantaloupe, and honeydew - Banana - Cucumber - Zucchini Symptoms often begin within minutes including itching or tingling of the lips, mouth, or palate, sometimes with mild localized swelling. GI symptoms such as heartburn, abdominal pain, diarrhea, and constipation can also develop in some patients. Food symptoms may become more noticeable during pollen season, but they can happen year-round. However, having ragweed allergy does not mean you will react to these foods. DO YOU NEED TO STOP EATING THESE FOODS Keep eating foods you tolerate. A cross-reactivity list is not a list of foods everyone with ragweed allergy must avoid. If a raw food repeatedly causes symptoms, stop eating that form and discuss it with your clinician. Cooking often breaks down the proteins responsible for pollen-food allergy syndrome, so cooked forms may be tolerated. Peeling and removing seeds sometimes helps but does not reliably prevent a reaction. Reactions to cooked foods, worsening symptoms, or symptoms beyond the mouth need further evaluation. Do not assume cooking makes a food safe after a serious reaction. Your clinician can help determine what to avoid and whether you need an epinephrine autoinjector. WHEN A FOOD REACTION NEEDS URGENT CARE Most pollen-food reactions stay mild and localized, but serious reactions can occur. Trouble breathing or swallowing, voice changes, faintness, or rapidly progressing throat or tongue swelling are emergency signs. Use epinephrine immediately if available and call 911. Antihistamines do not replace epinephrine for anaphylaxis. Mild lip swelling is different from swelling that affects the airway, but any progression needs prompt attention. Widespread hives or repeated vomiting after eating also require urgent assessment, especially when symptoms involve more than one part of the body. HOW TO GET AHEAD OF FALL ALLERGIES Check local pollen counts, keep home and car windows closed on high-pollen days, and shower and change clothes after prolonged outdoor exposure. Antihistamines can relieve itching and sneezing. For persistent nasal symptoms, especially congestion, a daily corticosteroid nasal spray is often the most effective single treatment. Some patients benefit from a nasal antihistamine or a combination spray. Starting an appropriate regimen before your usual season can improve control. Consider allergen immunotherapy (aka allergy shots) to can change your immune reactions to allergens over time and diminish your underlying allergic disease. Immunotherapy also treats seasonal respiratory allergy and reduces pollen-food reactions.  At Pienkowski MD, we help patients understand their allergy triggers and develop a treatment plan that fits their symptoms. Explore pienkowskimd.com for clinic information in Knoxville, Greeneville, Johnson City, Kingsport, and Bristol. Go Vols!

Evaluation of anaphylaxis risk by skin testing with Covid-19 messenger RNA vaccines on patients with anaphylaxis

By admin • November 17, 2021
Anaphylaxis Risk Analysis via Skin Testing with Covid-19 Vaccines Vaccination has been found to be effective in reducing the risks of infection of severe acute respiratory syndrome coronavirus and severe coronavirus disease 2019 (COVID-19) outcomes. In the United States, Pfizer-BioNTech and Moderna COVID-19 vaccines (aka the messenger RNA [mRNA] vaccines) have been used safely for these purposes. 1 , 2 PATIENT HISTORY OF ANAPHYLAXIS First post-market reports on the use of these vaccines describe 4.7 cases of anaphylaxis per million doses of Pfizer vaccine 3 and 2.5 cases per million Moderna doses given. 4 These early reports also describe 43.8 cases of non-anaphylactic allergic reactions per million Pfizer doses given. Among individuals who experienced anaphylaxis to the Pfizer vaccine, 81% had a documented history of allergies triggered by drugs, vaccines, medical products, foods or insect stings, and 33% of these individuals experienced anaphylaxis in the past. Similarly, 90% of individuals with a history of anaphylaxis to the Moderna vaccine had a documented history of allergic reactions, and 50% of these individuals experienced anaphylaxis in the past. POLYETHYLENE GLYCOL IN mRNA VACCINES The presumed causes of allergic reactions are the different polyethylene glycols (PEGs) in the mRNA vaccines. Although PEG allergy is rare, PEG has been found to cause anaphylaxis. 5 Moreover, skin testing of PEGs of differing molecular weights has been found to be effective in confirming anaphylaxis to PEGs in patients with a documented history of anaphylaxis to PEG. 6 Nevertheless, in a cohort of 8 individuals with allergic reactions to the first dosage of an mRNA vaccine, PEG skin testing result was found to be negative. 7 VACCINE PARAMETERS The 2012 vaccine practice parameters published by the American Academy of Allergy, Asthma, and Immunology (AAAAI), recommend that individuals with suspected anaphylaxis to a particular vaccine receive skin testing with that vaccine to evaluate their risk of anaphylaxis. 8 Because the mRNA vaccines contain components other than PEG that may cause allergic reactions, the AAAAI recommendations for evaluating risk of anaphylaxis to vaccines are appropriate for the mRNA vaccines as well. In fact, Greenhawt et. al. 9 recently suggested using the 2012 parameters for patients with a previously documented allergy to one of the mRNA vaccines. 9 Many of our patients who have experienced anaphylaxis express hesitancy toward receiving vaccines, owing to fears of anaphylaxis, and continue to delay their COVID-19 vaccination. To meet this demand, we offered skin testing with mRNA vaccines for our patients who requested evaluation of their risk of anaphylaxis. INITIAL TESTING In this communication, we will describe our first 30 patients (female, n = 27; male, n = 3) who had skin testing with the mRNA vaccines. The patients were either self-referred or referred to us by other physicians. All patients had a self-reported history of anaphylaxis to a variety of substances, including foods, venoms, drugs, environmental, flu vaccine, unknown sources or the first dosage of a COVID-19 mRNA vaccine. The risks and benefits of skin testing were discussed with the patients, and consent forms were accordingly signed. The patients were probed for self-reported reactions to PEG-containing products (ie, toothpaste and colonoscopy preparation). Ages of the patients ranged from 27 to 80 years. Of the patients, 2 had a history of COVID-19 confirmed by polymerase chain reaction testing. Disclosures: The authors have no conflicts of interest to report. Funding: The authors have no funding sources to report. https://doi.org/10.1016/j.anai.2021.09.021 ABOUT THE TEST Skin testing occurred from January 22, 2021, to March 25, 2021. Remnants of the mRNA vaccines were collected on the morning of testing from the Johnson City Medical Center in coordination with the Tennessee Department of Health and used for skin testing within 6 hours from opening of the vials. The patients were advised to refrain from using antihistamines and oral glucocorticoids starting 3 days before the testing. Skin testing was performed on the ventral forearms of the patients using the protocol recommended by the AAAI with modifications to increase safety. Testing began with stan- dard histamine and normal saline applied by prick technique and by intradermal injection of 0.05 mL of each as positive and negative con- trols, respectively. Next, a 1:10 dilution with normal saline of the Pfizer or Moderna vaccine was applied by prick technique. After 20 minutes, wheal sizes were measured and recorded. Whenever the result was negative, every 20 minutes a dosage of 0.05 mL of diluted vaccine was applied intradermally, starting with a 1:1000 dilution, then a 1:100 dilution, and finally a 1:10 dilution. After recording the final wheal size, pictures of the skin tests were taken, the patients were observed for an additional 30 minutes, and they were requested to submit pictures of their skin test at 4 to 6 hours after testing to evaluate late-phase reactions and at 24 hours after testing to evaluate delayed reactions. Afterward, the patients were evaluated by direct interviews for their reaction to subsequent vaccination. RESULTS The results are presented in Table 1 . There were 5 patients who had positive immediate skin reactions at doses ranging from 1:100 to 1:10 dilution of an mRNA vaccine. Of these patients, 1 had an anaphylactic reaction during skin testing of 1:100 dilution of the Moderna vaccine. These 5 patients also had positive late-phase reactions. There were 6 patients who had late-phase reactions without immediate reactions. Unfortunately, most patients did not comply with our request to submit pictures from delayed reaction. Patients with positive immediate reactions were recommended to receive the Janssen COVID-19 vaccine. Patients with negative immediate reactions (n = 25) were recommended to receive their choice of COVID-19 vac- cine. None of the patients with negative skin test result to an mRNA vaccine who were subsequently vaccinated to COVID-19 (n = 19, con- firmed through records in the Tennessee Immunization Information System) have had any allergic reaction to vaccination. After our risk assessment, 66% of the patients went on to receive full COVID-19 immunization.