These days, it seems like just about everyone has an allergy — and that’s not so far from the truth.
In 1970, only 10 percent of Americans suffered from a rhinitis allergy, the miserable runny-nose, watery-eye reaction associated with hay fever and other
seasonal woes. By 2010, the percentage had grown to 30 percent.
The number of U.S. children with food allergies increased by 50 percent between 1997 and 2011, while the number of kids with peanut allergies tripled from 1997 to 2008. In Europe, hospital admissions for severe allergies rose
sevenfold from 2003 to 2013.
We are in the throes of a global allergy epidemic.
Many health experts view the present moment as a perfect storm of allergy-inducing factors: Climate change is causing longer warm seasons and more pollen exposure; allergenic weeds are on the rise due to increased carbon emissions; and the decreasing quality of our food damages our microbiomes and, by extension, lowers our immunity. In addition, more than 100,000 new chemicals have been developed for use in material goods in just the past few decades, according to a study published in the journal Allergy, Asthma & Immunology Research. Of these chemicals, only a small percentage have been tested for their long-term health effects.
Despite all this, there is hope. As allergies are on the rise, so is knowledge among health experts about how to build resistance and stay healthy in a challenging environment. Here’s what they’re learning.
It’s in the Air
The dramatic uptick in allergies is linked to an increase in many forms of pollution, says Leo Galland, MD, a New York City–based functional-medicine practitioner and coauthor of The Allergy Solution.
Today, upward of 253 million vehicles travel on United States roadways, an increase from around 74 million in 1960, and their exhaust and particulate matter harm us directly, says Galland. Exposure to air pollution can trigger inflammation and oxidative stress in the lining of the respiratory tract and also increase our vulnerability to allergies by sensitizing these tissues. Still, traffic emissions are hardly the only source.
Forest fires have increased substantially because of climate change, scientists report. Fires now start earlier in the season and burn hotter and longer than in times past, all of which affect air quality. Their thick, black smoke can travel hundreds of miles and “is directly toxic to everyone,” Galland states.
Backyard fire pits and outdoor, open-flame cooking have similar effects. All wood smoke contains fine particulate matter and toxic chemicals, including benzene, formaldehyde, acrolein, and polycyclic aromatic hydrocarbons, according to the Environmental Protection Agency. This problem particularly affects people in impoverished areas around the world who use open-flame cooking indoors.
Toxic chemicals in our indoor environments have also multiplied dramatically. They hide in seemingly benign places — cleaning supplies, cosmetics, new furniture, and carpets that release chemicals into the air, resulting in that signature “new” smell.
Studies by the Environmental Working Group show that routine chemical exposure increases our overall “toxic burden” — the accumulation of chemicals that can be measured in our bloodstreams at any one time. This can change immune-system function, says Galland, making us more prone to allergic reactivity.
Some pollutants are double trouble. Carbon emissions, in particular, are not only airborne particulates, but they feed certain flora and make it easier for allergenic plants like ragweed to flourish.
In a study published in the Journal of Allergy and Clinical Immunology, researchers planted ragweed across central Baltimore as well as in suburban, semirural, and rural locations in Maryland. The urban ragweed “grew faster, flowered earlier, and produced significantly greater aboveground biomass and ragweed pollen” in the warmer, carbon-dioxide-rich urban locations than in the cooler, less-polluted rural locations, the study authors found. For anyone susceptible to allergies, an increase in pollen counts means a more severe allergic reaction.
As temperatures rise globally, the season for allergies begins earlier and ends later, so sufferers are not just sicker — they suffer longer. A 2015 report from the World Allergy Organization summed up these effects, noting that climate change “affects the start, duration, and intensity of the pollen season on the one hand, and the rate of asthma exacerbations due to air pollution, respiratory infections, and/or cold air inhalation, and other conditions on the other hand.”
This soup of airborne pollutants can be a toxic diet for the lungs. “The lungs have their own microbiome,” explains P. Michael Stone, MD, MS, an Ashland, Ore.–based functional-medicine physician. Airborne toxins take a toll on this delicate microbial ecosystem, weakening our defenses against allergies.
The sheer number of toxicants we are now exposed to daily “leads to imbalances,” says Gregory Plotnikoff, MD, MTS, FACP, a functional-medicine practitioner in Minneapolis. Overexposure triggers inflammatory processes in our bodies that would normally resolve when a threat has passed; instead they get stuck in the “on” position and “we can’t turn them back off,” he says. The result can be chronic inflammation.
What does chronic inflammation have to do with allergies? Ongoing inflammation interferes with the function of the body’s regulatory T-cells, explains Galland. Also known as T-regs or T-lymphocytes, these cells are responsible for turning off the immune response. When T-regs aren’t functioning properly, they don’t respond to the signal to stand down, and an ordinary immune response never resolves.
This is how we end up with autoimmune conditions, when the body attacks healthy tissue as if it were an allergen.
“The immune system works through balance,” says Galland. “When you have an excess of activity in some part of the immune system, it’s because of a failure of the mechanisms designed to control it.”
Diets on Fire
The food you eat can either help your body defend itself or fan the flames that lead to allergies. Like environmental toxins, the standard American diet — processed and fast foods high in sugar and unhealthy fats and low in protective phytonutrients — can trigger chronic inflammation. It’s bereft of foods that support microbial diversity, and it’s low in fiber, which is essential for healthy digestive function.
Because around 70 percent of the immune system is located in our gastrointestinal tract, optimal digestion and a diverse gut microbiome with enough beneficial bacteria are critical to reducing susceptibility to allergies and allergic reactions.
Processed foods often contain synthetic food additives, colorings, and preservatives that can also challenge digestion and provoke symptoms. Robyn O’Brien, founder of AllergyKids Foundation, points to the parallel rise of synthetic additives in the food supply and the spike in food allergies, intolerances, and sensitivities. She believes the body interprets some additives as invaders that require an immune response.
Pesticides and herbicides in conventionally grown foods may also be partly to blame for the rise in allergies and sensitivities. A 2013 study published in the journal Interdisciplinary Toxicology implicates glyphosate, the key ingredient in Roundup (an herbicide frequently applied to wheat crops), in the rise of celiac disease and gluten sensitivity.
Likewise, a 2012 study published in the Annals of Allergy, Asthma & Immunology found a class of chemicals called dichlorophenols (DCP) — which are created during the breakdown of common pesticides and commonly found in tap water — that correspond strongly to the presence of at least one allergy.
Of the 2,211 study subjects, 1,016 had an environmental allergy (ragweed, pet dander) and 411 had food sensitivities. While most subjects had DCP in their urine, those with the highest levels were nearly twice as likely as those with the lowest levels to test positive for a food sensitivity, usually to peanuts, milk, or eggs. (Wheat, corn, and chocolate are other common food triggers.)
What’s the difference between allergies and sensitivities? They’re distinguished mainly by the allergy pathway involved. The immunoglobulin E (IgE) allergic reaction carries no mystery. IgE antibodies are released instantly and produce unambiguous symptoms like sneezing, watery eyes, and, most seriously, anaphylaxis.
An immunoglobin G (IgG) reaction is slower and doesn’t have the same unmistakable antigen-antibody response. Its symptoms are subtler — headaches, fatigue, or constipation. One can have an IgG response to a particular food for years without ever knowing it, while an IgE response can’t be ignored. (For more details on the differences, see below.)
Finally, exposure to excess antibiotics, common for people with frequent infections, kills the good bacteria in the gut along with the bad microbes they target.
Before the advent of antibiotic-resistant bacteria and our present understanding of the “good bacteria” in the microbiome (something that would have once sounded like a contradiction), many doctors didn’t give antibiotics much thought; they were seen as wonder drugs. “When I trained as a pediatrician, we didn’t think twice about giving people antibiotics,” says Plotnikoff. Now most practitioners know better.
In addition, it’s common to see antibacterial hand-sanitizer pumps in the hallways of schools and the aisles of grocery stories. Plotnikoff is concerned that their overuse is harming our immunity and allergy resilience. “We’ve been raised in a culture that fears bacteria, so we get rid of all of them — even the good ones.”
The idea that our obsession with destroying germs is related to the rise of allergies is called the hygiene hypothesis. (For more on this, see “Dirt, Germs, and Other Friendly Filth“.) Galland emphasizes this cannot be the endpoint of any discussion about the rise in allergies (because it “lets polluters off the hook,” he says), but it does appear to be one aspect of the complicated matrix.
For example, some research suggests that total avoidance of certain foods might actually increase the risk of allergies to them. Take peanuts. The dramatic rise in peanut allergies that began in 1997 prompted health professionals to recommend that pregnant and nursing mothers avoid peanuts and not feed them to children until age 3. These guidelines were rescinded in 2008, since little research supported them, and a study published in JAMA Pediatrics in 2014 found children whose mothers consumed higher quantities of nuts during their pregnancies had lower rates of nut allergies.
Earlier this year, the National Institute of Allergy and Infectious Diseases recommended feeding babies as young as 4 to 6 months old peanuts to give them a better chance of staving off potential allergies. This suggests early exposure may help build an immunity that tolerates the food.
The Great Shape-Shifter
Allergies, intolerances, and sensitivities don’t always turn up as a runny nose and itchy eyes. According to Leo Galland, MD, coauthor of The Allergy Solution, allergies are “great mimics” because they can manifest in unexpected ways. Many people may be suffering an allergy or sensitivity-related symptom and have no idea that an underlying immune reaction is the root cause.
These are some of the common symptoms of a sensitivity-related reaction or allergy that, on the surface, appear to be something else.
• Weight gain: Allergies can lead to unexplained weight gain, or an inability to lose weight despite changes in diet and lifestyle. Studies have also linked antihistamine use with increased body weight.
• Muscle aches: Sore muscles have been associated with some of the classic allergy manifestations, like asthma and eczema, and have been linked to certain food intolerances and reactions to specific metals, like nickel. Galland says many of his patients with a sensitivity to mold report muscle pain.
• Joint pain: Allergy-fueled arthritis, often triggered by problem foods, is one of the most common, well-established “hidden” allergies.
• Fatigue: Feeling tired as a result of a sensitivity has been dubbed allergic tension-fatigue syndrome, and a food intolerance — often to wheat, corn, milk, or chocolate — is likely the cause.
• Brain fog: Galland says trouble with concentration and memory is often linked to food intolerances and mold sensitivity.
• Bloating or stomachache: Food intolerances inflame the lining of the intestines, leading to cramping, bloating, and pain. A trigger food can also cause heartburn. An elimination diet may help root out the troublemakers.
• Headaches: Decades of research have linked headaches — both migraines and nonmigraines — to allergies. Among the most common triggers are toxic fumes and foods like chocolate, nuts, soy, citrus, coffee, and alcohol.
• Insomnia: A dairy intolerance may be the reason you’re having trouble falling asleep and staying asleep.
• Hair loss: Alopecia areata is an autoimmune condition in which hair loss on the scalp goes beyond normal pattern baldness. It is more common among those who have been diagnosed with allergies, such as to gluten. Avoiding exposure may help stop — and even reverse — the hair loss.
• Depression, mood disorders, or psychiatric symptoms: A German study recently found that people with doctor-diagnosed allergies had higher rates of psychiatric symptoms. Galland notes that teenagers with asthma are about three times more likely than those without an allergy to be diagnosed with depression or a bipolar disorder later in life.
Addressing allergenic forces — pollution, chemical exposure, a low-nutrient diet, and a -weakened microbiome — may seem daunting. These straightforward, lifestyle-based strategies can help reduce your allergy susceptibility.
• Eat plants. Because some 70 percent of your immune system is located in your gut, increasing your consumption of whole foods, especially plant-based foods, is one of the most direct ways to support immune defenses.
Make whole foods the mainstay of your meals, preferably ones that “look as close to the way they looked when they came out of the ground,” says Galland. This will ensure your consumption of processed foods is minimal. Opt for organic to protect yourself from pesticides and herbicides. Support your T-cells with foods high in folates, vitamin A, and plant compounds called flavonoids.
Galland suggests you emphasize these potent allergy-defense foods:
- Strawberries are high in the flavonoid fisetin, which helps protect T-regs from damage.
- Sweet potatoes contain high amounts of vitamin A.
- Lentils are chock-full of folates. (For more on folate, see “Follow the Folate“.)
- Parsley is rich in the flavonoid apigenin, which has anti-allergic and anti-inflammatory effects.
- Green and oolong teas are both bursting with protective flavonoids.
• Favor cooked over raw. Many raw foods are high in allergens, but cooking can help: Heat renders some allergenic proteins inert, says Plotnikoff. Someone who reacts to fresh apples may do just fine with sautéed apples, for example. (Anyone with an anaphylactic allergy should try this only with the support of his or her doctor, for obvious reasons.)
• Keep it fresh. Leftovers can cause problems for allergy sufferers. Histamines, an immune chemical released during allergic reactions, grow on foods the longer they sit. So while a meal straight off the stove might not cause a reaction, eating that same food two days later for lunch could trigger one.
• Support your digestive enzymes. “A lot of allergens are fragile, and the digestive enzymes in the stomach or pancreas will render them inert,” says Plotnikoff. But if you aren’t producing enough digestive enzymes, you won’t break down those allergens. Signs of weak digestion include burping, belching, gas, feeling full quickly, and acid reflux or gastroesophageal reflux disease (GERD). “Supplementation with digestive enzymes can make up for what isn’t there,” he adds. (For more on this, go to “Digestive Enzymes“.)
• Skip the antacids. Regularly taking antacids may suppress stomach acid, which is required for activating enzymes that help break down potential allergens.
“Antacids increase the development and triggering of food allergies by blocking the normal digestion of proteins to their smallest molecules,” explains Stone. “The longer someone is on acid blockers, such as proton pump inhibitors (PPIs), the greater the incidence of them developing food allergies and hypersensitivity.”
People on acid blockers also have trouble with complete digestion, he says, and aren’t able to absorb as many of the healing nutrients in the food they eat. While we often assume digestive problems are due to excess stomach acid, the problem more often is that we don’t have enough. (For more on dealing with acid reflux, go to “Natural Ways to Fight Heartburn“.)
• Heal your gut. “Gut health is the foundation for all health,” says Plotnikoff. “And proper digestion, absorption, and elimination are the signs of a healthy gut.”
Up your fiber intake by eating whole, green leafy vegetables and other plants; promote good gut bacteria by incorporating fermented foods, like sauerkraut, kvass, and kimchi; take a high-quality probiotic; and consider drinking bone broth or eating grassfed gelatin to help seal up a leaky gut lining — a common condition in allergy sufferers. (For more on this, see “How to Heal a Leaky Gut“.)
• Reduce plastic in your life. Plastic is everywhere, from computer keyboards to steering wheels. Finding ways to reduce exposure to it where you can — especially in contact with food — can make a big difference.
Most plastics contain the potentially hormone-disrupting chemical -bisphenol A, or BPA. Trade plastic food containers for glass or stainless steel. Never heat food in plastic, since heat leaches chemicals directly into the food. And if you do use plastic water bottles or food-storage containers on occasion, make sure they’re BPA-free, which some experts believe is less dangerous.
• Improve indoor air quality. Research suggests that 86 percent of air fresheners contain hazardous phthalates — even ones that are marked “all natural.” Dryer sheets are equally dangerous because the chemicals in them are heated and vented into the air.
New furniture (especially particleboard) and carpet can both release chemicals that end up in household dust. Opt for vintage or secondhand items when you can. You can also let new furniture breathe in an outdoor area for as long as weather permits.
• Clean up body-care and household-cleaning products. Steer clear of any products with synthetic fragrances, which often contain endocrine disrupters. Propylene glycol is a common additive in body-care products and an increasingly common allergic trigger for many people. Consult the Environmental Working Group’s Skin Deep database for a comprehensive guide to safe personal-care products. (For more on fragrances, go to “The Problem With Perfume“.)
• Embrace a few germs. A little exposure to dirt and germs helps keep the immune system in good working order, so stick to soap and water and stay away from the big guns, such as antibacterials and antimicrobials, as much as possible, says Galland. Be aware that antibacterial and antimicrobial chemicals can turn up in places beyond hand soap and household cleaners — like toothpaste and mattresses. Read labels.
• Get your vitamin D. “Ensuring a good vitamin D level year round supports balance and immune function,” says Plotnikoff. The Endocrine Society, which is considered by many to be the top authority on optimal vitamin D levels, recommends a blood serum level greater than 30 ng/ml, but Plotnikoff believes optimal levels are slightly higher, between 40 and 60 ng/ml.
To achieve a good baseline, he recommends getting your vitamin D levels tested and then adjusting your supplement accordingly. Just about everyone needs to supplement, he says, especially those who live north of the Mason-Dixon line or work long hours indoors and get less sunlight.
• Opt for natural antihistamines. When allergies do strike, Plotnikoff suggests, reach for a natural antihistamine combination like quercetin, stinging nettle, and vitamin C.
Reactions that affect the lungs, including asthma, might also be helped by increasing your body’s glutathione production. Glutathione is a powerful antioxidant produced by the body — and it plays a key role in tissue repair.
“For those with rhinitis manifestations, glutathione production is super important,” he adds. Sulphur-rich foods like garlic, onion, and broccoli boost glutathione in the body, or you can take a glutathione-supporting supplement, such as N-acetyl cysteine. (For more on glutathione, go to “Glutathione: The Great Protector“.)
How Toxic Exposure Leads to Allergies
While allergies and intolerances trigger different physiological reactions in the body, the basic process of sensitization is the same, explains University of Alberta researcher Stephen Genuis, MD, in a 2010 paper published in the journal Science of the Total Environment. It involves:
2. An overactive immune response and a decreased tolerance for multiple allergens
3. More symptoms triggered by ongoing, low-level exposure to a variety of toxins
The acronym for this process is TILT for “toxicant-induced loss of tolerance.” Exposure to one or more toxic stressors triggers the immune system and diminishes its resources. At the next encounter with the toxin, the depleted immune system hyper-responds and allergy symptoms appear — many of which extend far beyond the classic signs.
It doesn’t take a lot of exposure to some toxins to experience an impact. In fact, exposure can be so small that Genuis has an acronym for that, too: MATES, or “minute assorted triggers evoke symptoms.” In other words, when your body is highly sensitized by ongoing toxic exposure, eating a micro amount of a problem food, or inhaling a whiff of diesel exhaust, can trigger symptoms.
Allergy, Intolerance, or Sensitivity?
Traditional allergy tests register positive only when a food or other toxicant triggers an antibody called immunoglobulin E, or IgE. The presence of IgE in the body tells cells to produce histamines “with explosive force,” says Leo Galland, MD, a New York City–based functional-medicine practitioner. It is that instant flood of histamines that is responsible for the acute symptoms of an allergy, from sneezing and eye-watering to full-blown anaphylaxis. (Anyone who has been relieved of an acute allergic reaction by antihistamine drugs understands the IgE reaction intimately.)
But some irritants don’t trigger the IgE antibody pathway — and, hence, don’t show up on conventional allergy tests. Instead, they trigger the immunoglobulin G, or IgG, pathway, which leads to inflammatory symptoms like migraines, joint pain and arthritis, and abdominal pain. The most likely triggers for this pathway are particular foods. These reactions are often called sensitivities or intolerances rather than allergies, as they involve a subtler, nonhistamine reaction.
IgG reactions are difficult to detect because symptoms can set in up to 24 hours after exposure — and sometimes longer. When there’s a gap that long between a trigger and a stomachache or migraine, it can take some sleuthing to work out the cause. If you suspect a hidden intolerance or sensitivity, find a practitioner who tests for and treats IgG-type sensitivities. Those tests may include fecal and breath tests.
You can also try an elimination diet to see if it offers relief from digestive and other symptoms. (Download the elimination diet guide from the Institute for Functional Medicine at ELmag.com/ifmdetox.)