View clinical trials related to Ketosis.
Filter by:Altitude-related hypoxia decreases human functional capacity, especially during exercise. Even with prolonged acclimatization, the physiological adaptations are insufficient to preserve exercise capacity, especially at higher altitudes completely. Consequently, there has been an ongoing search for various interventions to mitigate the negative effects of hypoxia on human performance and functional capacity. Interestingly, early data in rodents and humans indicate that intermittent exogenous ketosis (IEK) by ketone ester intake improves hypoxic tolerance, i.e.by facilitating muscular and neuronal energy homeostasis and reducing oxidative stress. Furthermore, there is evidence to indicate that hypoxia elevates the contribution of ketone bodies to adenosine-triphosphate (ATP) generation, substituting glucose and becoming a priority fuel for the brain. Nevertheless, it is reasonable to postulate that ketone bodies might also facilitate long-term acclimation to hypoxia by upregulation of both hypoxia-inducible factor-1α and stimulation of erythropoietin production. The present project aims to comprehensively investigate the effects of intermittent exogenous ketosis on physiological, cognitive, and functional responses to acute and sub-acute exposure to altitude/hypoxia during rest, exercise, and sleep in healthy adults. Specifically, we aim to elucidate 1) the effects of acute exogenous ketosis during submaximal and maximal intensity exercise in hypoxia, 2) the effects of exogenous ketosis on sleep architecture and quality in hypoxia, and 3) the effects of exogenous ketosis on hypoxic tolerance and sub-acute high-altitude adaptation. For this purpose, a placebo-controlled clinical trial (CT) in hypobaric hypoxia (real high altitude) corresponding to 3375 m a.s.l. (Rifugio Torino, Courmayeur, Italy) will be performed with healthy individuals to investigate both the functional effects of the tested interventions and elucidate the exact physiological, cellular, and molecular mechanisms involved in acute and chronic adaptation to hypoxia. The generated output will not only provide novel insight into the role of ketone bodies under hypoxic conditions but will also be of applied value for mountaineers and athletes competing at altitude as well as for multiple clinical diseases associated with hypoxia.
Brief Summary: Ketones are a source of energy and signaling molecule that are produced by the body when not consuming any food or consistently eating a low-carbohydrate "keto" diet. Blood ketones can be used as a source of energy by the body, but they may also act as signals that impact how different cells in the body function. Recently, ketone supplements have been developed that can be consumed as a drink. These supplements can raise blood ketones without having to fast or eat a "keto" diet. Previous studies have shown that these supplement drinks can lower blood sugar without having to make any other dietary changes. Drinking these ketone supplements may therefore be an effective strategy to improve blood sugar control and influence how cells function. To find out if it is feasible for people with type 2 diabetes to drink these ketones supplements regularly over 90 days, we will compare between two groups in this study: one group that will be asked to drink ketone supplements, and one group that will be asked to drink a placebo supplement.
In a recent study (Poffé et al., 2019), we demonstrated that increasing the concentration of ketone bodies in the blood through the ingestion of a ketone ester (KE) post-exercise and just before sleeping time during a 3-week overtraining period resulted in suppression of the physiological symptoms of overtraining. Consistent KE intake improved endurance performance, positively affected the autonomic regulation of the heart, suppressed the increase of nocturnal sympathetic activity, and increased spontaneous energy intake. In addition, KE intake had a positive effect on muscular adaptive response, as evidenced by the significantly increased muscular angiogenesis. Therefore, in this study, we aim to investigate whether the oral administration of ketones after exercise and just before bedtime also has a positive effect on the adaptive response during a well-dosed endurance training program. Since suppression of nocturnal sympathetic activity can positively influence sleep quality, we will also study the effect of KE and the training period on sleep quality. To investigate this, we will use a randomized, placebo-controlled parallel research design. Well-trained male cyclists will participate in a fully controlled intervention period of 8 weeks. During the intervention period, participants will follow a supervised cycling training program (5-7 training sessions per week) with a gradual buildup aimed at improving endurance capacity. Throughout the intervention period, participants will ingest 25g ketone ester or a corresponding placebo after each training session and 30 minutes before bedtime. Endurance performance will be evaluated before the start of the training period (pretest), after week 3 (midtest), after week 7 (posttest) of the training period, and at the end of the training intervention (posttest+taper). Additionally, blood samples will be taken at the pre-test and post-test to analyze markers of hormonal status and inflammation. Muscle biopsies will be taken from the vastus lateralis muscle of the right leg at pretest and posttest to analyze cross-sectional area, muscle fiber typing, angiogenesis, protein synthesis and degradation, mitochondrial function, and energy substrate concentrations. One month after the intervention period, an additional biopsy will be taken to study changes in gene expression (epigenetic modifications). Sleep will be evaluated via polysomnography (PSG) at the pretest, midtest and posttest. Finally, before and after the training period, resting and exercise echocardiography will be taken to investigate investigate structural and morphological changes of the heart.
Patients hospitalized in intensive care between January 2014 and September 2021 for ketoacidosis complicated by organ failure in participating departments.
Ketones are a source of energy and signaling molecule that are produced by the body when not consuming any food or consistently eating a low-carbohydrate "keto" diet. Blood ketones can be used as a source of energy by the body, but they may also act as signals that impact how different cells in the body function. Recently, ketone supplements have been developed that can be consumed as a drink. These supplements can raise blood ketones without having to fast or eat a "keto" diet. Previous studies have shown that these supplement drinks can lower blood sugar without having to make any other dietary changes. Drinking these ketone supplements may therefore be an effective strategy to improve blood sugar control and influence how cells function. To find out if it is feasible for people with type 2 diabetes to drink these ketones supplements regularly over 90 days, we will compare between two groups in this study: one group that will be asked to drink ketone supplements, and one group that will be asked to drink a placebo supplement.
The aim of this study is to investigate the effect of oral ketone ester administration on sleep architecture. To investigate this, the investigators use a randomised, placebo-controlled, cross-over research design. The study comprises three experimental sessions, each separated by a one-week washout period. Two of the three experimental sessions consist of a 120 minutes cycling endurance training session (ET) two hours after breakfast and an evening high-intensity-interval training (HIIT) ending one hour before bedtime. After each training session, and 30 minutes before sleeptime, subjects receive a ketone ester or a control drink . To investigate the effects of strenuous exercise on sleep alone, an additional experimental session without exercise is added. Before bedtime, a venous blood sample is taken to evaluate hormones playing an important role in sleep regulation. During the experimental sessions, the subjects sleep in a sleep facility to evaluate quality of sleep. Time spent in different sleep phases is measured via polysomnography (PSG). Urine output throughout the day and night will be collected for measurement of urinary excretion of adrenaline and noradrenaline as an index of intrinsic sympathetic activity.
The aim of this study is to investigate the effect of oral ketone administration during and immediately after an ultramarathon. Potential changes in cognitive function (reaction time, number of errors), running performance, jump height, skeletal muscle inflammatory infiltration and hormonal alterations will be the main focus. In this context, subjects (n=24) will perform a 100km ultrarunning trail, while receiving either ketone ester (KE, n =12) or placebo (CON, n=12). Experimental measurements will be performed immediately before and after the ultramarathon as well as 24h after the ultramarathon.
The objective of this randomized crossover study is to examine the influence of consuming a ketone ester plus carbohydrate (KE+CHO) supplement on substrate oxidation and physical performance in 15 healthy adults. Following a 48-hr muscle glycogen normalization period, volunteers will consume either an isocaloric KE+CHO (KE: 573 mg KE/kg body mass, CHO: 110 g) or isocaloric CHO drink and complete 90-min of metabolically-matched, load carriage (~30% body mass) steady-state aerobic (~60 ± 5 % of VO2peak) exercise on a treadmill. Glucose tracers will be used to assess glucose turnover, and contribution to exogenous and plasma glucose oxidation. Serial blood draws will be collected during each trial to assess endocrine and circulating substrate responses. After steady-state exercise volunteers will complete a time to exhaustion (TTE) physical performance tests at 85% VO2peak on a treadmill. Volunteers will then be provided with food for the remainder of the day. Following a 10-hr overnight fast, volunteers will return to the laboratory and consume the same supplement (KE+CHO or CHO) as they did the previous day. Volunteers will then perform a 4-mile load carriage time trial on a treadmill. Following a minimum 7-day washout period, volunteers will return to the laboratory to complete the second arm of the study. The primary risks associated with this study include those associated with exercise, blood draws, and gastrointestinal discomfort from the KE+CHO supplement.
Lipedema is a female progressive fat disorder, characterized by a symmetrical increase in subcutaneous adipose tissue in the lower extremities with the exception of the waist. The condition is often misdiagnosed and underdiagnosed. The etiology is poorly understood. Affects about 11% of all women and may lead to pain and immobility. The pathophysiology may be related to sex hormones and inflammatory response. Lipedema fat has been reported not to respond to lifestyle changes or bariatric surgery, both in terms of weight loss and symptom reduction; including pain and quality of life. Clinical research on the effect of dietary interventions on lipedema does not exist, but a pilot study with a ketogenic diet showed a significant reduction in pain regardless of weight loss. The aim of the research project will be to investigate whether a ketogenic diet can be a treatment option for patients with lipedema. Therefore, a randomized controlled trial will be conducted to compare the effects of two diets. 1) energy-restricted ketogenic diet and 3) energy-restricted low-fat non-ketogenic diet for 8 weeks. Pain and quality of life will be mesured at start and immediately after the intervention. The hypothesis is that a ketogenic diet may reduce pain and improve quality of life.
The ketone body 3-hydroxybutyrate (3-OHB) is a naturally occurring energy substrate, and is associated with increased life span and improved health. We have previously shown that intravenous 3-OHB treatment increases myocardial blood flow > 70% in healthy humans and data from our group show that 3-OHB increases cardiac output by 40 % in patients with heart failure. In this study the investigators aim to investigate: 1. If this effect is reproducible with a commercially available oral ketone supplements 2. The safety of commercially available ketone supplements in heart failure patients