The Study
VLCD-Induced Weight Loss Improves Heart Rate Variability in Moderately Obese Japanese
This study watched 16 people lose weight and measured their heart patterns before and after. It found that their hearts seemed to work better after losing weight, but we don’t know if the diet caused it—maybe they slept better or exercised more too.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
When overweight people lose a lot of weight, their heart starts to relax more during sleep, like a tired muscle getting a better break.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 539 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes—better heart rhythm at night means less stress on the heart and improved recovery, which can lower long-term risk of heart problems.
- 2People lost 17.8% of their body weight; their heart's resting rhythm got slower and more variable (better), especially at night; blood pressure didn't change.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Experimental Biology and Medicine
Year
2001
Authors
Y. Akehi, H. Yoshimatsu, M. Kurokawa, Toshiie Sakata, Hiroshi Eto, Sukenobu Ito, J. Ono
Related Content
Claims (6)
People with lower body fat tend to have a slower resting heart rate and greater heart rate variability.
In moderately obese Japanese adults, losing 17.8% of body weight through a very-low-calorie diet and behavior therapy is linked to measurable increases in heart rate variability during nighttime, reflecting greater activity of the parasympathetic nervous system.
In moderately obese Japanese adults, greater reductions in body mass index are associated with larger increases in high-frequency heart rate variability after weight loss.
In moderately obese Japanese adults, losing weight improves heart rate variability more at night than during the day, showing that the nervous system's regulation of the heart is more impaired during rest and recovers more during nighttime after weight loss.
In moderately obese Japanese adults, losing weight with a very-low-calorie diet and behavior therapy does not change average blood pressure, but heart rate variability improves regardless of blood pressure changes.
In moderately obese Japanese adults, losing weight through a very-low-calorie diet and behavior therapy is associated with a decrease in the low-frequency to high-frequency heart rate variability ratio.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.