El proyecto EXTREME, en el que participan profesionales del HUN, busca personas con sobrepeso para estudiar el ayuno intermitente

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El proyecto EXTREME, en el que participan profesionales del HUN, busca personas con sobrepeso para estudiar el ayuno intermitente


The research is funded by the Government of Navarra; the team is also made up of HUN - Navarrabiomed and the company Making Genetics.

A multidisciplinary team made up of specialists and research staff from the Public University of Navarra (UPNA), the University Hospital of Navarra (HUN) and geneticists from the company Making Genetics, is looking for volunteers aged between 30 and 65 who are overweight or obese for the "EXTREME" research project, which aims to examine the efficacy and feasibility of intermittent fasting on the cardiometabolic health of people with these characteristics. The professionals involved from the HUN belong to the Endocrinology and Nutrition Service under the coordination of Ana Zugasti Murillo and Estrella Petrina Jáuregui. The hospital's participation in the project is managed by Navarrabiomed.

The project is funded by the Regional Government's Department of Economic and Business Development and has the approval of the Navarra Clinical Research Ethics Committee.

The EXTREME project offers a 12-week nutrition programme designed by experts in the field of nutrition and health. The volunteers, after a medical check-up to ensure that there is no medical contraindication to participate, will have weekly professional care and supervision throughout the study. Medical and nutritional assessments are carried out using state-of-the-art technology. To participate or request more information, please call 644 06 88 34 or contact by email at: extreme.tre21@gmail.com.

Hourly restriction of food intake

According to the scientific director of the study, UPNA professor Idoia Labayen Goñi, the "hourly restriction of food intake" (TRE) "involves eating without restriction of type or quantity of food during a set time slot to eat and fasting for the rest of the day. Its main objective is to maintain a constant daily cycle of eating and fasting, which allows stable and healthy circadian rhythms to be maintained". 

"The results of the first studies on ERT in humans are promising and suggest that it reduces body weight and appetite, while improving cardiovascular health in adults with pre-diabetes and in patients with metabolic syndrome," explains Idoia Labayen. However, "there is currently insufficient scientific evidence to recommend ERT as a treatment for obesity and the mechanisms by which it could improve cardiovascular health without imposed energy restriction are unknown," she says.

Circadian rhythms, food intake, personalised SRT

Idoia Labayen explains that the dietary patterns proposed by intermittent fasting are based on aligning food intake with the biological rhythms that occur every 24 hours and result from the interaction between endogenous circadian rhythms and environmental factors. "The endogenous circadian system consists of a central clock located in the hypothalamus and peripheral clocks that appear in each and every one of the organs and tissues that make up our organism. Light signals, sleep schedules and diet, among others, affect the synchronisation of circadian rhythms," he says.

In this context, diet functions as a time signal in many organs related to metabolism. According to the study's scientific director, irregular eating patterns as well as food intake over a prolonged period of time (e.g. a 14-hour eating window from 7 am to 10 pm) lead to alterations in circadian rhythms. This, in turn, increases the risk of developing obesity, cardiovascular disease and type 2 diabetes. 

In addition, "the conflict between the biological clock and the social clock is a well-known phenomenon. For example, some people consider it a problem not to have dinner with their family and/or friends if they are following an early ERT schedule, e.g. from 8am to 2pm. Moreover, Spain is one of the countries in the world where people eat dinner the latest, around ten o'clock", he says. Thus, "the EXTREME project arose in response to the need to examine the viability and acceptability of different ERT mealtimes in our social context, as well as to analyse their effectiveness", concludes Idoia Labayen.

Source: www.unavarra.es