Seasons of the year and body weight

Organisms adapt to changes in the environment, such as changes in light conditions (photoperiod) and temperature that occur throughout the year. These changes mark what we call seasonal rhythms, which consist of oscillations throughout the year observed in different physiological and metabolic processes and/or parameters (such as sleep, appetite regulation, body temperature or the release of some hormones).

A study shows that the beneficial effects of polyphenols in obesity may vary due to seasonal changes in the intestinal microbiota.

The results of the study carried out by a team that includes Verónica Arreaza-Gil, Cristina Torres and Anna Arola, all of them researchers from the Department of Biochemistry and Biotechnology of the Rovira i Virgili University (URV) in Tarragona, show for the first time in a model obesity animal, that the composition of the intestinal microbiota varies according to photoperiod conditions, one of the key characteristics of seasonal rhythms. This is of great importance, since this intestinal flora has been shown to play a fundamental role in maintaining the proper functioning of our body, its alteration being associated with various pathologies such as metabolic syndrome or obesity.

Thus, the composition of the intestinal microbiota could vary according to the season of the year, and these changes could determine a greater or lesser susceptibility to developing obesity. Specifically, this study has shown that rats housed in long photoperiod conditions (with more hours of light and therefore fewer hours of activity, since these animals are nocturnal) showed a greater alteration of the intestinal microbiota that was correlated with a further development of obesity.

If we were to extrapolate this to humans, what would be expected to be observed is that the changes in the intestinal microbiota observed in the period of the year when we have more hours of darkness and therefore less activity in general terms (since we are diurnal unlike the rodents), are associated with a higher risk of developing metabolic pathologies such as obesity. However, studies in this regard are necessary to confirm this hypothesis.

The results of the new study indicate that the seasons of the year influence the beneficial effects of bioactive compounds in the diet on obesity. (Image: Amazings/NCYT)

The study also shows that the beneficial effects of polyphenols (chemical compounds present in fruits and vegetables) to prevent or alleviate obesity change according to photoperiod conditions, due at least in part to these changes observed in the composition of the microbiota. intestinal. These results reinforce the theory that these intestinal bacteria play a very important role in mediating the effects of these bioactive compounds, which can be explained by the intervention of these bacteria in metabolic processes related to these polyphenols.

Thus, the polyphenols that we ingest with food reach the colon for the most part, where they are metabolized by the intestinal microbiota, giving rise to various phenolic compounds which may show different anti-obesogenic properties. Therefore, changes or alterations in these intestinal bacteria can give rise to different phenolic compounds and therefore to a change in their functionality, as the research team has observed in another unpublished study.

The now-published study highlights the great importance of chrononutrition, a novel and continuously growing field, in the treatment or prevention of diseases such as obesity.

The study is titled “The effects of grape seed proanthocyanidins in cafeteria diet-induced obese Fischer 344 rats are influenced by faecal microbiota in a photoperiod dependent manner”. And it has been published in the academic journal Food & Function. (Source: URV)