Can fasting improve cardiovascular health? Research shows that certain types of fasting, like intermittent fasting, can lead to positive changes in heart-related measures such as lower resting heart rate, better cholesterol levels, and improved blood sugar control. A study on healthy adults found that eight weeks of intermittent fasting boosted heart rate variability, a sign of stronger autonomic nervous system balance, and dropped resting heart rate from 74.8 beats per minute to 68.2 beats per minute. For more details, see this study at https://www.icr-heart.com/article/effect-of-intermittent-fasting-on-cardiovascular-autonomic-regulation-in-healthy-adults-2282/[1].
Intermittent fasting often means eating during set windows, like 16 hours of fasting followed by eight hours of eating, or fasting on certain days with only vegetables. In a six-month trial with 41 people, this approach cut body weight by 8 percent and body fat by 16 percent. It also improved lipid profiles with big drops in LDL cholesterol, non-HDL cholesterol, and triglycerides by up to 25 percent. Check the full trial results here: https://pmc.ncbi.nlm.nih.gov/articles/PMC12727815/[2].
These changes matter for the heart because high LDL and triglycerides build up in arteries, raising risks for blockages and heart disease. Fasting seems to trigger a metabolic switch where the body burns fat for fuel instead of sugar, which can lower inflammation and boost insulin sensitivity. One review notes benefits like lower cholesterol, blood pressure, and insulin resistance, especially when paired with weight loss[5]. A recent report even suggests intermittent fasting beats daily calorie cuts for lowering blood pressure and long-term heart risk estimates[4].
Fasting also helps with blood sugar markers tied to heart health. It reduced fasting blood sugar, insulin levels, insulin resistance via HOMA-IR, and HbA1c in some metabolic studies[3]. This points to better control over diabetes risk factors, which strain the cardiovascular system.
Not all fasting is the same, though. Skipping breakfast regularly links to higher cardiovascular disease risk, possibly from poor insulin response and more inflammation[6]. Structured intermittent fasting, done safely, shows more promise. It may promote autophagy, a cell cleanup process that cuts inflammation and protects heart cells[5].
Experts say these effects come from less overall calories, better hormone balance like GLP-1 signaling, and shifts in gut and lipid pathways[2]. Blood pressure drops were modest or not always significant, but trends go down over time[1][4]. Always talk to a doctor before starting, as fasting suits some people better than others.
Sources
https://www.icr-heart.com/article/effect-of-intermittent-fasting-on-cardiovascular-autonomic-regulation-in-healthy-adults-2282/
https://pmc.ncbi.nlm.nih.gov/articles/PMC12727815/
https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1664811/full
https://www.news-medical.net/news/20251217/Intermittent-fasting-edges-daily-calorie-cuts-for-blood-pressure-and-long-term-cardiovascular-risk-estimates.aspx
https://www.massgeneralbrigham.org/en/about/newsroom/articles/pros-and-cons-of-intermittent-fasting
https://pmc.ncbi.nlm.nih.gov/articles/PMC12702892/
