Sensitivity to common food allergens such as dairy and peanuts could be an important and previously unappreciated cause of heart disease, and could also increase the risk for cardiovascular death, even in people who don't appear to have allergies, a new study has said.

According to the study published in The Journal of Allergy and Clinical Immunology, this increased risk may be comparable to -- or even exceed -- the risks posed by smoking, diabetes, and rheumatoid arthritis.

Researchers looked at thousands of adults over time and found that people who produced antibodies in response to dairy and other foods were at elevated risk of cardiovascular-related death. 

The strongest link was for cow’s milk, but other allergens such as peanuts and shrimp were also significant. 

According to the researchers, this is the first time that "IgE" antibodies to common foods have been linked to an increased risk of cardiovascular mortality. 

“What we looked at here was the presence of IgE antibodies to food that were detected in blood samples,” said researcher Jeffrey Wilson, MD, PhD, an allergy and immunology expert at the University of Virginia School of Medicine. 

Approximately 15 per cent of adults produce IgE antibodies in response to cow’s milk, peanuts and other foods. While these antibodies cause some people to have severe food allergies, many adults who make these antibodies have no obvious food allergy, the study noted.

Researchers also found that the strongest link with cardiovascular death was in people who had the antibodies but continued to consume the food regularly -- suggesting they didn’t have a severe food allergy.

To see if other food allergies could be affecting the heart, a team of researchers reviewed data collected from 5,374 participants.

Among the participants, IgE antibodies to at least one food were associated with a significantly higher risk of cardiovascular death, the researchers found.

Additional analysis also identified peanut and shrimp sensitisation as significant risk factors for cardiovascular death in those individuals who routinely ate them.