What happens to your 'good cholesterol' when you swap carbs for fat or protein?
Partially Replacing Dietary Carbohydrate With Unsaturated Fat or Protein Shifts Protein-Based HDL Subspecies Toward Lower Coronary Heart Disease Risk
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Your blood has tiny cholesterol particles with different proteins on them. Some proteins help protect your heart, others might hurt it. This study found that eating less carbs and more healthy fat or protein changes these particles in ways that seem good for your heart.
Surprising Findings
Replacing carbs with protein lowered HDL cholesterol (a known ‘good’ marker) but still improved heart risk profiles by reducing harmful HDL subspecies.
For decades, doctors told us to raise HDL-C at all costs. This study shows you can lower HDL-C and still get heart benefits—shattering the ‘higher HDL = better’ myth.
Practical Takeaways
Swap one daily carb source (e.g., white bread, sugary cereal) with 1 oz of nuts or 3 oz of grilled fish/chicken.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Your blood has tiny cholesterol particles with different proteins on them. Some proteins help protect your heart, others might hurt it. This study found that eating less carbs and more healthy fat or protein changes these particles in ways that seem good for your heart.
Surprising Findings
Replacing carbs with protein lowered HDL cholesterol (a known ‘good’ marker) but still improved heart risk profiles by reducing harmful HDL subspecies.
For decades, doctors told us to raise HDL-C at all costs. This study shows you can lower HDL-C and still get heart benefits—shattering the ‘higher HDL = better’ myth.
Practical Takeaways
Swap one daily carb source (e.g., white bread, sugary cereal) with 1 oz of nuts or 3 oz of grilled fish/chicken.
Publication
Journal
Arteriosclerosis, Thrombosis, and Vascular Biology
Year
2025
Authors
Bo Zhang, Jeremy D. Furtado, Allison B. Andraski, Barry Guglielmo, Lawrence J. Appel, Kun Wang, Shin'ichiro Yasunaga, Keijiro Saku, Katsunori Ikewaki, Frank M. Sacks
Related Content
Claims (5)
When you eat more healthy fats or protein instead of carbs, it changes the different types of 'good cholesterol' in your blood in ways that affect how your body handles fat, blood clotting, and immunity — like your body has separate teams inside the cholesterol that respond to what you eat.
If you swap out 10% of the carbs in your diet (like bread or sugar) for healthier fats (like olive oil or nuts), your body might produce a little more of a good protein in your blood that helps protect your heart — and this change can happen in just four weeks if you have slightly high blood pressure.
If you swap out 10% of the carbs in your diet for more protein, it might lower certain proteins in your 'good cholesterol' that are linked to heart disease — and this change happens in people with slightly high blood pressure after just 4 weeks.
If you swap out carbs in your diet for healthy fats or protein, your body may make more of a good cholesterol protein that helps protect your heart, but less of another protein linked to heart disease risk — and this happens within just four weeks if you have slightly high blood pressure.
Eating a little less fat might lower your risk of heart disease by about 7%, but eating a little less carbs might raise your risk by 5%, no matter what kind of food you're eating.