Budoff Et Al 2024 Carbohydrate Restriction Induced Elevations In Ldl Cholesterol And Atherosclerosis

This groundbreaking study examined a concerning phenomenon that some people experience on ketogenic diets: dramatically elevated LDL ("bad") cholesterol levels. Researchers studied 80 lean, metabolically healthy individuals who developed LDL cholesterol levels of 190 mg/dL or higher (with some reaching as high as 591 mg/dL) after following ketogenic diets for an average of nearly 5 years. These individuals, dubbed "lean mass hyper-responders," typically have low triglycerides and high HDL ("good") cholesterol despite their elevated LDL levels.

The key question was whether these sky-high cholesterol levels were actually causing heart disease. To find out, researchers used advanced heart imaging (coronary CT scans) to measure actual plaque buildup in the arteries of these keto followers and compared them to a carefully matched control group with normal LDL cholesterol levels (averaging 123 mg/dL). Surprisingly, despite having cholesterol levels nearly 150 points higher on average, the ketogenic diet group showed no more coronary artery plaque than the control group.

Even more intriguingly, the study found no correlation between LDL cholesterol levels and plaque burden in either group, challenging the conventional assumption that higher LDL always equals more heart disease risk. The researchers were careful to exclude people with genetic conditions that cause high cholesterol, focusing specifically on diet-induced elevations.

These findings suggest that the traditional approach of judging heart disease risk solely by LDL cholesterol numbers may not apply to everyone, particularly metabolically healthy individuals following carbohydrate-restricted diets. For clinical practice, this research supports the importance of individualized cardiovascular risk assessment that looks beyond cholesterol numbers to include advanced imaging and metabolic health markers when evaluating patients following ketogenic approaches.