Trans fats increase stroke risk in postmenopausal women
Evidence continues to mount regarding the health impact of trans fats in one’s diet. According to a large new study, trans fats increase the risk of ischemic strokes in postmenopausal women. In addition, the report noted that the risk could be decreased with aspirin (An ischemic stroke is one due to a blockage of an artery, which results in lack of blood supply to a portion of the brain.) The study was published online on March 1 in the Annals of Neurology.
The researchers derived their data from 87,025 generally healthy postmenopausal women aged 50 to 79 years who were enrolled in the Women's Health Initiative Observational Study from 1994 through 1998. The investigators assessed the women’s diets via a self-administered food frequency questionnaire. The women were queried regarding their frequency of intake of fats in meat and dairy products, fats used in cooking, added fats, and reduced-fat foods during the previous three months. The women were evaluated at enrollment and at a follow-up visit three years later. The investigators documented 1,049 cases of ischemic stroke over 663,041 person-years of follow-up.
The study revealed that women in the highest quintile (highest 20%) of trans fat intake had a significantly higher incidence of ischemic stroke compared to women in the lowest quintile; in addition, the stroke risk was reduced in women who regularly used aspirin compared to those that did not. The researchers also found no significant relationships between the ingestion of other fats (saturated, monounsaturated, or polyunsaturated fat) and ischemic stroke. They also noted that the increased risk was not modified by major lifestyle variables, such as body mass index (BMI), smoking, or physical activity. Furthermore, the association between trans fats and stroke remained for health conditions such as a history of atrial fibrillation, coronary heart disease, or diabetes. Dietary factors such as significant ingestion of fruit and vegetables as well as Vitamin E supplements did not modify the risk.
The authors concluded that in the large study of postmenopausal women, higher intake of trans fat was associated with an increased risk of ischemic stroke independent of major lifestyle/dietary factors. In addition, the study suggested that aspirin use may reduce the potential adverse effect of trans fat intake on ischemic stroke.
The investigators also took into account that the women might reduce trans fats in their diet during the study period if thy suffered an adverse event such as a heart attack or the development of diabetes. This did occur in some of the study participants; however, it did not reduce their stroke risk.
Take Home Message:
Although this study was focused on postmenopausal women, it would be prudent for individuals of any age or gender to avoid trans fats. It would be inadvisable to continue with one’s unhealthy diet and pop an aspirin each day. A better approach would be to avoid the trans fats and discuss an aspirin regimen with a healthcare professional. Aspirin does reduce the risk of strokes or heart attacks; however, it has a risk of gastrointestinal bleeding.
Trans fats are produced by a chemical process known as partial hydrogenation. The purpose of the process is to extend a product’s shelf life and improve its taste. They are present in many processed foods such as buttery crackers, buttered popcorn, French fries, fish sticks, creamy frosting and pastries.
Reference: Annals of Neurology