Fasting

From the style of the language of the opening of this text it is clear that it was composed between 1790 and 1804 during the middle period of the reform movement established by the Shehu, which began in 1774 until his death in 1817. The specific target of this text was his son, Shaykh Muhammad Sanbu who requested the Shehu to put in writing some principles on the methodology of disciplining the soul through hunger and fasting. Shaykh Abd’l-Qaadir ibn Mustafa informs us in his Bayaan at-Ta`abudaat that as a result of applying the discipline of the text at the hands of his father, Shaykh Muhammad Sanbu ibn Shehu Uthman ibn Fuduye` had attained the station of champion of truth (siddiqiyya) at an early age. The general target audience of this text were the many spiritual disciples of the Shehu who were apart of his close assembly in Degel just before the hijra in 1804. Among them were Shaykh Umar Kamuni, Shaykh Muhammad Yero, Shaykh Abdullahi Mujjin Mahwi, Shaykh Muhammad Kari`angha, Shaykh Muhammad Tukur, Shaykh Ali Dhimbu, Shaykh  Shaykh Muhammad ibn al-Bukhari, Shaykh as-Sayyid Ibrahim, Shaykh Umar Ghurba, the wife of the Shehu A`isha Iyya Gharka bint Shaykh Muhammad Sanbu; and others. Shaykh Umar Ahmad Zaruq said that another important beneficiary of this text was the Shehu’s eldest son, Muhammad Sad, who died in the year 1791, which means the text was probably composed between 1789 and 1790. At the time of the composition, Shaykh Muhammad Sanbu was about 17 years old and Shaykh Muhammad Sa`d was about 20 years old.

We investigated whether spiders fed lipid-rich rather than protein-rich prey elevate metabolism to avoid carrying excessive lipid deposits, or whether they store ingested lipids as a buffer against possible future starvation. We fed wolf spiders (Pardosa prativaga) prey of different lipid:protein compositions and measured the metabolic rate of spiders using closed respirometry during feeding and fasting. After a 16-day feeding period, spider lipid:protein composition was significantly affected by the lipid:protein composition of their prey. Feeding caused a large and fast increase in metabolism. The cost of feeding and digestion was estimated to average 21% of the ingested energy irrespective of diet. We found no
difference in basal metabolic rate between dietary treatments. During starvation ˙VO2 and ˙VCO2 decreased gradually, and the larger lipid stores in spiders fed lipid-rich prey appeared to extend survival of these spiders under starvation compared to spiders fed protein-rich prey. The results show that these spiders do not adjust metabolism in order to maintain a constant body composition when prey nutrient composition varies. Instead, lipids are stored efficiently and help to prepare the spiders for the long periods of food deprivation that may occur as a consequence of their opportunistic feeding strategy.

Background  High-quality methods for lipoprotein characterization are warranted in studies on various metabolic diseases.Materials and methods  An automated system for size-exclusion chromatography (SEC) of lipoproteins using commercially available components is described. Cholesterol or triglyceride content in separated lipoproteins from plasma and interstitial fluid (IF) was continuously determined on-line using microlitre sample volumes.Results  The lipoprotein assay showed a good concordance with the classic ultra-centrifugation/precipitation technique using fresh or frozen samples. Determination of lipoproteins in IF obtained from vacuum-induced skin blisters from 18 healthy subjects revealed that very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol levels were 18%, 19% and 25%, respectively, of concomitant plasma concentrations. The size-exclusion chromatography (SEC) system also allows for triglyceride determination on-line and it could be shown that the system is advantageous for an accurate determination of triglycerides in conditions when there are high levels of glycerol, e.g. in mice and in patients with hyperglycerolaemia (pseudo-hypertriglyceridaemia).Conclusions  The described system should be of value in studies where detailed lipoprotein analysis is warranted and particularly when significant sample series with small volumes are available. Our data also suggest that there is a 4–5·5-fold concentration gradient between plasma and IF for the three major plasma lipoproteins.

Fasting is a common phenomenon and can either be intended or unintended. It can be self-imposed in the case of extreme dieting, religious fasts, and chaotic work schedules. It can be medically-imposed in the case of fasting before blood draws or surgery. In extreme cases, it can be caused by external circumstances such as food shortages, natural disasters, or poverty.
Food deprivation has been shown to alter the quantity of food people but or consume. However, little attention has been given to how fasting affects the composition of people's food choices. Do people simply buy more when they are food deprived, or do they specifically increase purchases of high-calorie, relative to low calorie, foods?
There is some reason to suspect that shifts in food purchases following deprivation would favor high-calorie foods. That is, fasting has been shown to increase brain reactivity to particular types of food over others. Fasting subjects showed increased activation in brain areas associated with reward, including the ventral striatum, amygdala, anterior insula, and medial and lateral orbiofrontal cortex (OFC), in response to high-calorie, vs. low-calorie, foods.
If one;s physiological reactivity to high-calorie foods is increased following fasting, it may well be that people would also choose more of those foods relative to low-calorie foods. Indeed, a recent lunchtime dining study demonstrated a shift towards more high-calorie options following 18-hour fasts. Such fasts may not be frequent or regular, but short periods of deprivation - such as skipping a meal - are fairly common. If shifts towards a higher-calorie shopping basket occur even with short-term deprivation, this would increase the importance of such findings for a wide number of groups ranging from meal-skipping dieters to overworked residents.

This article compares the findings of three studies that explored the role of increased blood glucose in improving memory function for subjects who ate breakfast. An initial improvement in memory function for these subjects was found to correlate with blood glucose concentrations. In subsequent studies, morning fasting was found to adversely affect the ability to recall a word list and a story read aloud, as well as recall items while counting backwards. Failure to eat breakfast did not affect performance on an intelligence test. It was concluded that breakfast consumption preferentially influences tasks requiring aspects of memory. In the case of both word list recall and memory while counting backwards, the decline in performance associated with not eating breakfast was reversed by the consumption of a glucose-supplemented drink. Although a morning fast also affected the ability to recall a story read aloud, the glucose drink did not reverse this decline. It appears that breakfast...

Mammals and birds adapt to prolonged fasting by mobilizing fat stores and minimizing protein loss. This strategy ends with an increase in protein utilization associated with behavioural changes promoting food foraging. Using the Zucker rat as a model, we have investigated the effect of severe obesity on this pattern of protein loss during long-term fasting. Two interactions between the initial adiposity and protein utilization were found. First, protein conservation was more effective in obese than in lean rats: fatty rats had a three times lower daily nitrogen excretion and proportion of energy expenditure deriving from proteins, and a lower daily protein loss in various muscles. This phase of protein sparing is moreover nine times longer in the fatty rats. Second, obese animals did not show the late increase in nitrogen excretion that occurred in their lean littermates. Total body protein loss during starvation was larger in fatty rats (57% versus 29%) and, accordingly, total protein loss was greater in their muscles. At the end of the experiment, lean and obese rats had lost 98% and 82%, respectively, of their initial lipid reserves, and fatty rats still had an obese body composition. These results support the hypothesis that in severely obese humans and animals a lethal cumulative protein loss is reached long before the exhaustion of fat stores, while the phase of protein conservation is still continuing. In contrast, in lean rats, survival of fasting seems to depend on the availability of lipid fuels. The data also suggest that accumulation of too much fat in wild animals is detrimental for survival, because it eliminates the late phase of increase in nitrogen excretion that is linked to a food foraging behaviour anticipating a lethal depletion of body reserves.

There is evidence that changes in branched-chain amino acid (BCAA) levels may correlate with the efficacy of therapeutic interventions for affecting improvement in metabolic control. The objective of this study was to evaluate whether serum concentrations of BCAAs (leucine, isoleucine, valine) could mediate in insulin sensitivity and glucose tolerance after continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnea (OSA). A prospective randomized controlled trial of OSA patients with morbid obesity was conducted. Eighty patients were randomized into two groups: 38 received conservative treatment and 42 received CPAP treatment for 12 weeks. Plasma levels of BCAA, glucose tolerance and insulin resistance were evaluated at baseline and after treatment. After treatment, significant decreases of leucine levels were observed in both groups when compared with baseline levels (P < 0.005). With respect to patients with normal glucose tolerance (NGT), pat...

Cardiovascular risk factors are known to exacerbate high-saturated fatty acid meal (HSFAM)-induced endothelial dysfunction, but the influence of subclinical metabolic dysregulations and the acute impact of a single mixed Mediterranean-type meal (MMM) remains unknown. Thus, this study has the objective to evaluate the metabolic and vascular effect of such meals in healthy subjects with or without subclinical fasting metabolic dysregulations. Twenty-eight healthy males without overt cardiovascular risk factors randomly ingested 1 of 2 isocaloric meals on separate days. Plasma metabolic markers, fatty acid (FA) profile, and endothelial function (flow-mediated dilatation; FMD) were assessed at baseline and 2 and 4 h after meal ingestion. Unsupervised hierarchical clustering identified 2 subgroups of participants (n = 11 and 17) differing by their baseline metabolic profiles. The MMM did not significantly alter postprandial endothelial function in all subjects, irrespective of baseline m...

1. The tolerance of chickens to acute heat stress, evaluated by the time required to reach the critical body temperature (Tr) of 44.5 degrees C, was markedly enhanced as the period of fasting was extended. 2. Fasting reduced the rates of heat-induced changes in blood acid-base and electrolyte status. 3. Changes in Tr were correlated with changes in blood pH, pCO2, [Cl-] and [Pi] but not with changes in [Na+] or [K+]. 4. Blood acid-base and electrolyte status were related to Tr rather than time of exposure to heat stress.

Imaging of the metabolism of hyperpolarized [1-(13) C]pyruvate has shown considerable promise in preclinical studies in oncology, particularly for the assessment of early treatment response. The repeatability of measurements of (13) C label exchange between pyruvate and lactate was determined in a murine lymphoma model in fasted and non-fasted animals. The fasted state showed lower intra-individual variability, although the [1-(13) C]lactate/[1-(13) C]pyruvate signal ratio was significantly greater in fasted than in non-fasted mice, which may be explained by the higher tumor lactate concentrations in fasted animals. These results indicate that the fasted state may be preferable for the measurement of (13) C label exchange between pyruvate and lactate, as it reduces the variability and therefore should make it easier to detect the effects of therapy. © 2016 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.

The Sirt1/AMPK signaling pathway is a key sensor of energy status and regulates glucose and lipid metabolism. Leucine (Leu) activates Sirt1 by lowering its Km for NAD(+) and potentiates other sirtuin/AMPK-activators, resulting in improvement of insulin sensitivity. Since metformin (Met) converges on this pathway, we hypothesized that leucine would amplify its gluco-regulatory effects. The effects of Leu (24g/kg diet)+Met (0.05-0.5g/kg diet) combinations were compared to standard therapeutic Met (1.5g/kg diet; ~300mg/kg BW) on glycemic control in high fat diet induced insulin resistant mice for 6weeks. The effects of Leu on Met stimulation of Sirt1 and AMPK activities were further evaluated in adipocytes. Sub-therapeutic levels of Met combined with Leu resulted in increases in Sirt1 activity and in tissue P-AMPK/AMPK ratio and corresponding dose-responsive improvements in fasting and post-prandial glucose, in glucose response to an insulin tolerance test and in the area under the cur...

There is no agreement on how to manage hunger strikers. The health professionals called to intervene in a hunger strike are faced with a dilemma: commit themselves to good order and discipline or comply with best practices for providing healthcare. Handling cases of hunger strikers confronts practitioners with the ethics dilemma of managing apparent intentional behavior that carries serious morbidity or mortality, but recognizing that hunger striking is a military and political tactic, and not a medical condition. The study by Reeves, et. al published in the Journal enhances our understanding of the motives and psychology of hunger strikers. Their analysis indicates that improving communication with custody administration and mitigating unnecessarily aversive housing environments can likely reduce the incidence of hunger strikes.

This report describes the performance of a wireless electronic diary (e-diary) system for data collection and enhanced patient-investigator interactions during intensive insulin management in diabetes clinical trials. We implemented a customized electronic communication system featuring an e-diary and a Web portal in three global, randomized, controlled Phase 3 clinical trials testing basal insulin peglispro compared with insulin glargine, both combined with prandial insulin lispro, in patients with type 1 or type 2 diabetes mellitus (T1DM and T2DM, respectively). We collected data during 28 weeks of study e-diary use for the report. Patients (n=2,938) in 31 countries used e-diaries to transmit 2,439,087 blood glucose (BG) values, 96% of which were associated by the patient with a protocol time point during the 72-h response window. Of 208,192 hypoglycemia events captured, 96% had a BG value, and 95% had treatments and outcomes entered by patients within the 72-h window. Patients re...