Eating a diet with lots of red meat has long been considered a risk factor for cardiovascular disease.
But now a study has found that those who are allergic to red meat, specifically the complex sugar in such meat called alpha-gal, also seem to be at increased risk for the buildup of plaque in the arteries, which increases the risk of coronary artery disease.
To arrive at this finding, Dr. Coleen McNamara, professor of medicine in the Cardiovascular Research Center of the University of Virginia Health System, and her team examined blood work from 118 Virginia patients. They found 26 percent of participants created the IgE antibodies to alpha-gal. This indicated they had the allergy to mammals’ meat, which is known as alpha-gal syndrome.
They then found that, as they’d suspected, that the group reactive to alpha-gal had 30 percent more plaque accumulated in their arteries than other participants. Those in the study with the alpha-gal allergy, especially those over the age of 65, also tended to have plaque that was more unstable. This means they were at greater risk for a heart attack or stroke.
A red meat allergy develops from a bite from a Lone Star tick, which seems to prime the immune system to react to the alpha-gal carbohydrate. Alpha-gal syndrome is most common in southeastern United States. However, as this tick’s population grows, the condition is rising in central and northern states as well.
“Given evidence that the Lone Star tick sensitizes individuals to the alpha-gal modification associated with red meat allergy and the Lone Star tick is prevalent in regions of the southeast that have increased rates of heart artery disease, we hypothesized that the two may be connected,” McNamara told Allergic Living.
The lead study researcher stresses two takeaways from the study, which was published in 2018. “We need additional research in this area to confirm findings and to determine mechanism and causality,” McNamara told Allergic Living.
“No change in recommended health behaviors is needed. People should continue to follow the American Heart Association guidelines for heart-healthy living.” (These include regular exercise, not smoking, following a heart-healthy diet, maintaining healthy weight, and seeking treatment for high blood pressure, high cholesterol or Type 2 diabetes.)
McNamara’s co-authors, Dr. Scott Commins and Dr. Thomas Platts-Mills, were the first to report on red meat allergy in 2009.
McNamara and her team are also studying the disease mechanism and the cause and effect relationship “to provide greater insights into whether this is more than an association.”
See Allergic Living’s feature report “The Rise of Red Meat (Alpha-Gal) Allergy“.