Recurrent circadian fasting (RCF) improves blood pressure, biomarkers of cardiometabolic risk and regulates inflammation in men

Abstract

Background The effects of fasting on health in non-human models have been widely publicised for a long time and emerging evidence support the idea that these effects can be applicable to human practice. Methods In an open label longitudinal follow-up, a cohort of 78 adult men (aged 20 to 85 years) who fasted for 29 consecutive days from sunrise to sunset (16 h fasting—referred to as recurrent circadian fasting) in Pakistan, were studied. The primary outcomes of the fasting study was weight loss/recovery and the associated changes in blood pressure and circulating levels of surrogate markers linked to organ and system functions—including cardiovascular, metabolic and inflammation. Post-fasting outcomes include the regulation of physiological biomarkers. Results Recurrent circadian fasting with weight loss reduced blood pressure (140.6 vs. 124.2 mmHg) and markers of cardiovascular risk (~ 4-fold for resistin; triglycerides: p < 0.0001). Reduced glycemia (p < 0.0001) and the associated changes in the regulation of ketosis (β-hydroxybutyrate) were accompanied by a metabolic shift (PPARβ, osteoprotegerin), suggesting the involvement of the different physiological systems tested. Elevated orexin-A levels (p = 0.0183) in participants indicate sleep disturbance and circadian adaptation. All participants had CRP level < 2 mg/l during the fasting period and a similar trend was observed for TNFα. While most SASP molecules were decreased after the fasting period, heightened levels of IL-8 and IL-6 suggest that some inflammatory markers may be elevated by recurrent circadian fasting. Importantly, older adults reveal similar or more substantial benefits from fasting. Conclusions Recurrent circadian fasting is beneficial at the cardiometabolic and inflammatory levels, especially for at-risk individuals—this is contingent on compliance towards the recommended dietary behaviour, which controls carbohydrate and caloric intake. These benefits from fasting may be particularly beneficial to older adults as they often exhibit abnormal cardiovascular, metabolic and inflammatory signatures. Electronic supplementary material The online version of this article (10.1186/s12967-019-2007-z) contains supplementary material, which is available to authorized users.

Effect of diurnal intermittent fasting during Ramadan on ghrelin, leptin, melatonin, and cortisol levels among overweight and obese subjects: A prospective observational study

“…During the DIF of Ramadan, drastic changes in the timing and frequency of fluid and food intake have been reported [ 27 ], which contribute to chronobiological changes in the circadian rhythms that regulate body temperature, blood glucose, cortisol, and melatonin levels, and day- and night-time wakefulness [ 22 ]. Bogdan and colleagues have previously reported that DIF during Ramadan, along with the concomitant changes in social habits, psychology, and sleep schedules induce changes in the rhythmicity of levels of several hormones such as cortisol, melatonin, and leptin [ 28 , 29 ]; however, the authors did not account for the body weight of the study participants, nor did they examine how changes in anthropometric measures, diet, and lifestyle during Ramadan impact these hormonal changes.…”

Ramadan Fasting and Risk of Coronavirus Disease 2019 (Covid-19) in Healthy People: A Review

“…fasting showed a beneficial effect on health. A cohort study was done by Alam et al, 2019 29 on 78 adult men who were fasted for 29 consecutive days from sunrise to sunset in Pakistan, aged 20 to 85 years, All CRP level < 2 mg/l during the fasting period and a similar trend were observed for TNFα. Most SASP molecules were decreased after the fasting period, heightened levels of IL-8 and IL-6 suggest that some inflammatory markers may be elevated by recurrent circadian fasting.…”

C-Reactive Protein and White Blood Cell Count in Non-Infective Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis

“…It is worth mentioning that in reference to another blood parameter such as glucose, its values measured fasting the next morning after admission had more potent long-term prognostic significance than the admission values [ 22 ]. Therefore, as levels of CRP might be biased by food intake [ 17 ], we measured CRP levels in our AIS patients after at least 6 h overnight fasting [ 21 ], according to our institutional protocol [ 22 ]…”

“…Therefore, previous studies might have produced inconsistent findings of the prognostic role of CRP in AIS patients due to the variable and inadequate threshold of a biomarker used. CRP level and WBC may also be affected by measurements which took place in different clinical conditions, such as different time of the day, after previous food intake and under the influence of non-steroidal anti-inflammatory drugs [ 17 , 18 , 19 ]. For example, fasting is associated with a significant decrease in the CRP level [ 17 ], whereas WBC increases by nearly 10% two hours after meal consumption [ 19 ].…”