New research challenges the widespread belief that white meat, such as chicken, is better for cholesterol levels than red meat, such as beef, pork, or lamb.
A new study breaks some bad news for meat eaters, as researchers find that white meat is just as harmful to cholesterol levels as red meat.
The paper counters the widespread belief that white meat is more healthful than red. This belief relies on a variety of observational studies that have found a link between red meat intake and a higher risk of cardiovascular disease.
However, the authors of the new research argue that the connection between white meat and cholesterol has not received enough attention in specialized literature.
So, a team of researchers — spearheaded by senior author Dr. Ronald Krauss, senior scientist and director of Atherosclerosis Research at the Children's Hospital Oakland Research Institute in California — set out to investigate this link in more detail.
Dr. Krauss and colleagues tested how different meat intakes affected the levels of lipids and lipoproteins that can cause fatty deposits to form on the arteries. They published their findings in the American Journal of Clinical Nutrition.
Comparing meat and nonmeat intake
The researchers divided healthy men and women into two groups, according to whether they regularly consumed high levels of saturated fatty acids or low levels of saturated fatty acids.
Within these two arms of the study, the researchers randomly assigned the participants to a red meat group, a white meat group, and a nonmeat protein diet group.
Within each group, the participants — who were 21–65 years old and had a body mass index of between 20–35 kilograms/square meter — consumed the allocated foods for 4 weeks.
After the intervention, the researchers measured low-density lipoprotein (LDL) cholesterol ("bad" cholesterol), levels of apolipoprotein B, small and medium LDL particles, as well as total and high-density lipoprotein (HDL) cholesterol ("good" cholesterol).
Red and white meat have 'identical' effects
The study found that abstaining from eating meat altogether lowered blood cholesterol much more than researchers had previously believed.
Consuming both red and white meat raised blood cholesterol levels more than consuming equivalent levels of plant-based proteins. "This was due primarily to increases in large LDL particles," note the authors.
The raised levels of cholesterol did not depend on whether the diets also had high levels of saturated fats.
"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."
Dr. Ronald Krauss
The senior author adds that non-meat protein sources, such as vegetables, dairy, and pulses, have the most beneficial effect on cholesterol levels. However, the authors also note that the study did not include grass-fed beef, fish, or processed meats.
"The findings are in keeping with recommendations promoting diets with a high proportion of plant-based food but, based on lipid and lipoprotein effects, do not provide evidence for choosing white over red meat for reducing [cardiovascular disease] risk," write the researchers.
Dr. Krauss and colleagues conclude, "the present study is the first to show that both categories of meat protein result in LDL concentrations that are higher than those resulting from vegetable protein sources in otherwise comparable diets."