Gluten-Free Research Roundup
The latest medical news for people with allergies and food sensitivities
Farms & Pets Reduce Allergies
Growing up on a farm is associated with lower rates of allergies and asthma. Now a new study has homed in on some of the immune mechanisms that may provide protection from allergic disease. In particular, it found that key cells, known as dendritic cells, appear to play an important role in the effect of farm exposures on childhood allergy. Growing up with dogs or cats also had immune-modulatory effects but these were different from the effects seen in farm exposures (e.g., drinking farm milk and playing in stables and hay barns).
The thinking is that growing up with a dog, cat or on a farm exposes kids to more bacteria and a greater variety of bacteria. These bacteria may be helpful in programming their maturing immune systems. The study was published in December 2015 in the Scandinavian Journal of Immunology and Clinical & Experimental Allergy.
More on the Microbiome
Researchers from the University of Oregon have added a new nugget to our understanding of the gut microbiome. They recently discovered that some species of bacteria don’t need to be present in large numbers to exert a powerful effect. In studies with “germ-free” zebra fish, researchers found certain species of bacteria were able to completely control an inflammatory response, despite being far outnumbered by a species of bacteria shown to be highly inflammatory. It turns out these so-called minority species secrete molecules—not yet identified—that allow them to tamp down the immune response of the whole community.
The role of minority species in the microbiome has garnered little attention until now. The new findings, published in November 2015 in Cell Host & Microbe, suggest that the contribution of each bacterium is not equal. If researchers identify a disease state where a key minority species is missing, it may one day be possible for a specific probiotic to restore healthy functioning.
Infertility & Celiac Disease
A number of studies have shown higher rates of infertility in women with undiagnosed (hence, untreated) celiac disease. But not all studies have been consistent—in part because of different study methods—and awareness of celiac disease as a possible factor in infertility remains spotty. Now research that pooled data across numerous studies on infertility and celiac disease is calling renewed attention to the link. It showed women with infertility were three times more likely to have celiac than women without infertility. When infertility was unexplained (i.e., there was no identifiable cause, such as no sperm issues or blocked fallopian tubes) women were six times more likely to have celiac disease. Findings were published in January 2016 in the Journal of Clinical Gastroenterology.
Processed Food & Autoimmunity
Food additives in processed foods have been linked to increased intestinal permeability (leaky gut) in a new report. Published in June 2015 in Autoimmunity Reviews, the report identified several common food additives that may weaken tight junctions in the intestine. These additives include glucose (sugar), salt, gluten, emulsifiers (e.g., sucrose esters, mono- and diglycerides), microbial transglutaminase (found in meat labeled “formed meat” and some dairy) and nanoparticles (miniscule bits of nonfood items, such as titanium dioxide, that are added to some processed foods to make them more visually appealing).
Leaky gut has been said to play a role in a number of autoimmune diseases, including celiac disease, type 1 diabetes and multiple sclerosis. The new research was prompted by the observation that consumption of processed food has skyrocketed alongside rates of autoimmune diseases.
Importantly, the study didn’t prove food additives cause autoimmune disease. However, its authors suggest limiting exposure to these food additives if you’re at greater risk for developing an autoimmune condition (i.e., due to family history). To reduce your exposure, stick to whole, single-ingredient foods.
Babies & Gluten
Recently, GF&M reported that it doesn’t matter when babies are first introduced to gluten. Results from two major clinical trials showed the timing of gluten introduction has no bearing on celiac risk. However, a new study published in November 2015 in Clinical Gastroenterology and Hepatology raises the question of whether the amount of gluten may still be important.
The study from Sweden showed infants genetically predisposed to celiac disease had an increased risk of the disease if they were fed larger amounts of gluten before age 2. Tots under age 2 who consumed more than 5 grams of gluten per day had double the risk of celiac disease compared to those who consumed less than 3.4 grams of gluten per day. Five grams of gluten is about the equivalent of one slice of whole wheat bread.
The new study wasn’t as rigorous in its study design as the two randomized clinical trials that concluded timing of gluten introduction didn’t influence celiac risk. One of these trials looked at the effect of introducing gluten early in very small amounts versus regular amounts later on; results suggested this didn’t reduce celiac risk. Still, this latest study may have some at-risk families wondering if they should strictly limit the amount of gluten given to their babies. Check with your pediatrician.
For more on this topic, see GlutenFreeAndMore.com/gluten-and-your-baby.
Omega-3s May Ward Off Rheumatoid Arthritis
New research suggests omega-3 fatty acids may help guard against the development of rheumatoid arthritis (RA). The study included 77 healthy people with risk factors for RA (i.e., family history). Thirty study participants also had a key RA auto-antibody called anti-CCP2. Auto-antibodies like anti-CCP2 are thought to precede the onset of RA symptoms, which include joint pain, stiffness, swelling and redness.
According to the study, just 7 percent of those with this RA auto-antibody took an omega-3 supplement compared to 34 percent without the auto-antibody. In addition, omega-3 levels in the blood were significantly lower in those with the RA auto-antibody.
Omega-3s, especially EPA and DHA, may help reduce inflammation and impede the development of RA auto-antibodies during the period before symptoms emerge.
Omega-3s can be found in wild-caught, cold-water fish, like salmon and mackerel, and in fish oil supplements.
The current study, which looked only at omega-3 supplementation (not dietary intake), was too small to suggest an ideal dose to reduce RA risk. Researchers hope to track a larger group of patients over a longer period of time to look at the effect of omega-3 supplementation over time and to examine dose and duration. Results were published online in September 2015 in Rheumatology.