You’ve probably seen headlines contending that according to a new study, gluten-free diets are “bad for your heart,” “raise heart attack risk,” “do more harm than good” and should be avoided by everyone except the 3 million Americans with celiac disease, a digestive disorder that damages the small intestine. People who have it cannot eat gluten, a protein found in wheat, barley and rye.
Actually, there is scientific evidence that people with certain genes DO benefit from following a gluten-free diet to protect their heart health–even if they don’t have celiac disease. That’s why the BaleDoneen Method, which uses genetic tests to identify the best diet for each patient, continues to recommend a gluten-free diet for people with these genotypes. Here’s a closer look at the new study, which was widely misunderstood by the media, and how to tell if you should consider going gluten free to reduce heart attack and stroke risk.
Did the study find any evidence that gluten-free diets raise heart attack risk?
Although the study, which was published in British Medical Journal (BMJ), initially found a lower rate of cardiovascular events (such as heart attacks and strokes) in people who ate the most gluten, versus those who ate the least, the researchers reported that after adjusting their results for a variety of risk factors, the difference “was no longer significant.”
The researchers concluded, “Long-term dietary consumption of gluten was not associated with risk of coronary heart disease (CAD).” [Emphasis added.] That means there was no link between how much or how little gluten the people studied ate and the likelihood that they’d develop CAD (plaque in the arteries that can lead to a heart attack or stroke).
How was this study conducted?
Participants were not asked if they ate a gluten-free diet. Instead, they filled out questionnaires every four years that asked about their medical conditions and how often they’d eaten various foods in the past year. The study included about 100,000 men and women with no history of CAD or celiac disease.
The researchers estimated how much gluten each person ate and divided the study participants into five groups, from the highest consumption to the lowest. The study looked at rates of CV events over a 26-year period, which turned out to be similar in all groups after adjustment for CAD risk factors, such as obesity, age, and smoking.
Since the researchers found no link between gluten-free diets and heart attack risk, why did they warn against this diet for people without celiac disease?
The researchers point out that people with celiac disease are at increased risk for CAD, which can be reduced with a gluten-free diet. For everyone else, the study argues that avoiding gluten might reduce people’s consumption of whole grains, which contain heart-healthy fiber. Several studies show that eating whole grains, while limiting or avoiding refined grains (such as white bread and most baked goods), does help protect against CV events.
However, large studies around the world also report that the more servings of fresh fruit and vegetables people eat daily, the lower their risk for heart attack and stroke. Not only is fresh produce high in fiber, but it also contains many other valuable nutrients known to enhance cardiovascular wellness. Therefore, whole grains that contain gluten are not crucial for heart health.
Why does the BaleDoneen Method recommend gluten-free diets for people with certain genes?
Unlike the BMJ study, which did not take genetics into account, the BaleDoneen Method uses genetic testing to identify the best diet for each individual. To tell if you’d benefit from a gluten-free diet, we use a blood test to analyze your haptoglobin (Hp) genotype, which offers insight into your heart disease risk and which foods and supplements are beneficial for you.
The Hp gene regulates haptoglobin, a protein produced by your liver that binds to hemoglobin, a substance produced when red blood cells die. If hemoglobin isn’t bound quickly, it releases iron, which can have a variety of harmful effects on arterial health, including oxidizing LDL (bad) cholesterol, making LDL even more dangerous!
The Hp gene has two alleles, Hp 1 and Hp 2. Since you inherit one allele from each parent, there are three possible genotypes: Hp 1-1 (associated with low risk for CAD), Hp 1-2 (intermediate risk) and Hp 2-2 (high risk). Recent studies suggest that people with the Hp 1-2 and Hp 2-2 genotypes benefit from a gluten-free diet as part of their heart-attack-and-stroke-prevention plan, while there’s no CV advantage for those with the Hp 1-1 genotype.
How does going gluten free help people with those genotypes?
Recent research has identified Hp2’s precursor protein, zonolin, as “the biological door to inflammation, autoimmunity and cancer.” As discussed more fully in our book, Beat the Heart Attack Gene, chronic inflammation is a key player in causing CAD. Once plaque has formed in the arteries, this fiery process can also ignite a heart attack or stroke. Think of plaque as kindling and inflammation as the match.
Since gluten activates the zonolin pathway with adverse effects on the intestines, the lining of blood vessels and other parts of the body, increasing risk for chronic disease, including CAD, we recommend that people with the Hp 1-2 and Hp 2-2 genotypes limit or avoid gluten in their diet and consider taking a daily probiotic supplement, after consulting with their medical provider to make sure this is appropriate for them.