Normal IgA levels protect the body against infections, allergies, and autoimmunity. Low levels usually point to a weakened immune system. Read on to learn about the factors that may balance the immune response by increasing IgA levels.
IgA levels are a marker of immune health. Low or high levels don’t necessarily indicate a problem if there are no symptoms or if your doctor tells you not to worry about it.
Improving your IgA levels won’t necessarily directly cause any kind of improvement in immune balance, but it can be used as a biomarker for your immune health.
The following are a list of complementary approaches to improve immune health and that have also been found to improve IgA levels.
Though studies suggest various dietary and lifestyle factors may increase IgA levels, additional large-scale studies are needed. Remember to talk to your doctor before making any major changes to your day-to-day routine.
Supplements that May Improve Immune Health (as Measured by IgA)
Chewing gum containing L. reuteri significantly increased IgA in the saliva (DB-RCT) .
In a study (DB-RCT) of 66 pregnant women, high-dose multi-strain probiotics resulted in infants with higher IgA levels and improved gut function .
The probiotic VSL#3 increased IgA production in monkeys .
Gut bacteria may be important for IgA production. Germ-free mice have greatly reduced IgA production in the gut. Even a single strain of bacteria can effectively promote the production of gut IgA in germ-free mice [10, 11].
Prebiotics are food for good bacteria. They improve our gut microbiome.
In a study (DB-RCT) with 187 infants, those who were exclusively fed formula and given prebiotics had higher IgA levels than infants who received a placebo .
Yacon flour, which is 50 – 70% prebiotic fiber, taken for 18 weeks increased IgA in 59 preschool children .
A prebiotic taken during pregnancy increased IgA levels in maternal milk in mice .
Glutamine increased nasal but not salivary IgA during high-intensity interval training in 13 runners .
Four weeks of chlorella supplementation increased IgA in 15 men .
Chlorella also increased resting IgA in 26 subjects in intensive training .
Finally, chlorella increased IgA concentrations in breast milk of 18 pregnant women .
However, at its higher dosage, it also blocked IgA release .
Dietary Factors that May Improve Immune Health (as Measured by IgA)
In 15 obese subjects, a 14-day fast increased blood IgA levels .
7) Vitamin A
Vitamin A-deficient rats and mice have decreased levels of total IgA in the gut, but their blood IgA levels are normal .
Breast milk of women supplemented with vitamin A had higher levels of IgA .
In 24 volunteers, IgA production increased in those who ate white button mushrooms .
White button mushrooms increased IgA in mice .
Lifestyle Changes that May Improve Immune Health (as Measured by IgA)
9) Reducing Chronic Stress
Acute stress (lasting a few minutes to a few hours) tends to stimulate the immune response .
Examination stress increased IgA levels in 15 nursing students. IgA decreased again two hours after the examination .
Contrarily, chronic stress, over a period of several days, weeks or months, decreases the immune response .
Chronic stress was associated with lower IgA in middle-aged and elderly subjects .
Perceived stress was associated with lower IgA in dental students .
In toddlers attending center or family childcare at home, children with a lower quality of childcare had lower IgA levels .
Low IgA is thought to be an important underlying mechanism linking chronic stress with increased upper respiratory tract infections .
Managing stress can help reverse the decrease in IgA. A study in 32 women showed that viewing unpleasant pictures decreased IgA levels. However, a reinterpretation of the situation (cognitive reappraisal) reversed the decrease of IgA .
Directly tied to reducing chronic stress, relaxation techniques can improve immune function and increase IgA levels.
In 24 volunteers, 20 minutes of relaxation significantly increased IgA production. Additionally, those who had practiced relaxation once a day for three weeks had larger increases in IgA levels than those practicing for the first time .
Ten minutes of relaxation increased IgA in 79 Japanese female medical workers .
In 14 breast cancer patients, IgA was higher after surgery in those who participated in a relaxation method called autogenic training .
People who use humor as a coping skill have higher baseline IgA levels .
Similarly, a funny presentation increased IgA levels in 21 fifth-graders compared to 18 of their classmates who watched an educational presentation .
Stressful events decrease IgA levels. Among 40 subjects, those with a sense of humor were less likely to have IgA reduced by stress .
Similarly, in a group of 66 college students, those exposed to background music for 30 minutes had increased IgA levels .
Another study also showed that college students listening to music had increased IgA .
Participating in music may have an even greater effect.
Out of 33 subjects, those who actively sang or played percussions had greater increases in IgA levels than people who only listened to music .
Another study showed that singing in the choir increases IgA .
13) Short/Moderate Exercise
IgA levels increase in response to short-term or moderate exercise. This can help reduce the risk of respiratory infections .
Regular, moderate exercise increased IgA at rest in 9 subjects compared to 10 sedentary controls .
In 45 elderly individuals, 60-minute resistance and 60-minute moderate endurance training once a week significantly increased IgA after 12 months .
14) Avoiding Strenuous Exercise
IgA levels change depending on the intensity and duration of exercise, as well as the type of physical activity. Prolonged exercise decreases, while short-term and moderate exercise increases, IgA levels [73, 74, 75, 76, 68].
Professional athletes have lower IgA levels and are more prone to upper respiratory tract infections .
In 155 ultra-marathoners IgA levels decreased after racing .
Another study found that IgA also decreased in 64 ultra-marathon racers and 43 participants of an open water swimming race .
In soccer players, IgA decreased following training but returned to pre-training levels after 18 hours of rest. Overnight rest was sufficient for IgA recovery following training, but not following two successive matches .
In 13 international soccer players, IgA levels progressively declined during a four-day training period .
In 26 elite swimmers with a seven-month training season, pretraining salivary IgA levels were 4.1% lower with each additional month of training. Post-training IgA levels were 8.5% lower for each additional 1 km swum in a training session and 7.0% lower for each additional month of training .
Adolescent volleyball players had lower IgA levels compared with sedentary volunteers .
15) Enough REM Sleep
In a study of 32 volunteers, IgA levels decreased during four nights of REM sleep deprivation, but not after total sleep deprivation. The IgA levels did not return to baseline even after three nights of sleep recovery .
Some drugs can block REM sleep and may decrease IgA levels. These include antidepressants and sympathomimetics (drugs that mimic the action of adrenalin and dopamine and activate the sympathetic nervous system) [84, 85].
Salivary IgA increases during sleep. In mice with disrupted circadian rhythms, salivary IgA failed to increase during sleep. It was shown that the increase in IgA was dependent on the sympathetic nervous system (fight-or-flight) activation, which is associated with REM sleep [86, 87].
16) Smoking Cessation
A couple of studies indicated that smoking tobacco and cigarettes can decrease IgA levels.
Tobacco chewers and tobacco smokers had decreased IgA levels compared to nonsmokers. Further, smokers had significantly lower IgA levels than chewers .
In mice, three months of cigarette smoke exposure before influenza virus infection resulted in reduced IgA levels and increased lung inflammation .
However, some studies showed no differences in IgA levels in smokers .
17) Bright Light
18) Sexual Activity in Moderation
Among 112 college students, those who had frequent sex had the highest IgA levels. The relationship between sexual activity and IgA levels had a reverse ‘U’ shape, with both those having very frequent and infrequent sex having lower IgA levels .
Further studies will hopefully clarify this point.
19) Breastfeeding (in Babies)
Infants receive IgA via breast milk. Then IgA production in the gut is gradually stimulated by developing gut microbiota .
20) Thermal Water Inhalation
Thermal water comes from hot springs. It rises from deep underground and absorbs beneficial minerals on the way to the surface.
In 100 children with respiratory infections, those who inhaled sulfurous thermal water had higher blood IgA and better infection outcomes .
In another study, 25 patients treated with thermal water had increased nasal IgA compared to 25 patients treated with distilled water .
Low IgA signals weakened immunity. Studies suggest that certain lifestyle and dietary changes may improve the immune response (and increase IgA levels). Though more research is needed, promising results were seen with probiotics, prebiotics, glutamine, vitamin A, and fasting. Studies suggest that taking up a relaxation technique, avoiding chronic stress, getting enough sleep and moderate exercise, quitting cigarettes, and having a good sense of humor may also strengthen the immune response and increase IgA.