Red, white meats equally detrimental to blood cholesterol
Red and white meat have equally harmful effects on blood cholesterol levels, according to research published in the American Journal of Clinical Nutrition, contradicting the popular idea that lighter proteins like chicken are more heart-healthy than their counterparts like beef and lamb.
The APPROACH (Animal and Plant Protein and Cardiovascular Health) trial’s results surprised senior author Ronald Krauss, MD, and his colleagues at the University of California, San Francisco Children’s Hospital Oakland Research Institute, who hypothesized red meat would have a more dramatic effect on individuals’ cholesterol levels compared to white meat or plant proteins, the other two food sources they considered.
“When we planned this study, we expected red meat to have a more adverse effect on blood cholesterol levels than white meat, but we were surprised that this was not the case—their effects on cholesterol are identical when saturated fat levels are equivalent,” Krauss said in a release.
In the study, which didn’t include fish, grass-fed beef or processed products such as bacon or sausage, Krauss and co-authors assigned generally healthy men and women aged 21-65 to one of two parallel arms, one of which involved high saturated fatty acid (SFA) content to raise LDL-cholesterol and the other of which involved low SFA. Within those groups, patients were allocated to red meat, white meat and non-meat protein diets for four weeks each in a random order.
The authors found red and white meat similarly increased amounts of large cholesterol-enriched LDL particles—which have a weaker connection to CVD than smaller LDL particles—while plant-based diets didn’t. Since standard LDL-cholesterol tests primarily reflect levels of larger LDL particles, that means using standard LDL-cholesterol thresholds as a measure of cardiovascular risk might lead to overestimating that risk for higher meat and saturated fat intake.
Krauss et al. reported the best cholesterol benefit came from non-meat proteins like vegetables, dairy and legumes.
Government dietary guidelines recommend people opt for poultry instead of red meat, but Krauss noted there haven’t been any comprehensive studies comparing the effects of white, red and plant-based proteins on blood cholesterol until this point.
“Our results indicate that current advice to restrict red meat and not white meat should not be based only on their effects on blood cholesterol,” he said. “Indeed, other effects of red meat consumption could contribute to heart disease, and these effects should be explored in more detail in an effort to improve health.”