Having late eating habits - such as breaking the overnight fast after 9 in the morning or eating dinner after 9 at night - is unhealthy and increases cardiovascular risk, especially in women, while having breakfast and dinner before 8, by extending overnight fasting, you reduce the risk of suffering from cerebrovascular diseases, such as stroke.
This is clear from the results of a study carried out by a team from the Barcelona Institute for Global Health (ISGlobal), INRAE, Inserm and the Universtié Sorbonne Paris Nord following the eating habits of more than 100,000 people for a median of seven years.
"Our findings suggest that, beyond the nutritional quality of the diet, meal timing may help promote better cardiovascular health," says Anna Palomar-Cros, first author of the study. And she specifies that, based on the results obtained (which should be replicated in other studies to provide greater evidence), "the recommendation is to have breakfast before 8 in the morning and have dinner before 8 at night, fasting until daylight." following".
According to the ISGlobal researcher, eating the first meal of the day later than that time has been associated with cardiometabolic risk factors: increased blood pressure, greater inflammation or increased insulin level. And a later last meal "was associated with higher glycated hemoglobin (which may be a risk factor for cardiovascular disease) and may contribute to glucose intolerance, insulin resistance, higher cholesterol levels, and an increase in body mass index, as indicated by human trials.
The scientific team studied associations between food intake patterns and cardiovascular diseases in 103,389 people (79% women) taking into account a large number of confounding factors, both demographic (sex, age, family situation, etc.) and nutritional quality. of diet, lifestyle and sleep cycle.
The results, published in Nature Communications, indicate a 6% increased risk of cardiovascular disease for every hour breakfast is delayed. In the case of dinner, eating it after 9 pm is linked to a 28% increase in the risk of suffering from cerebrovascular pathologies. On the other hand, a longer duration of overnight fasting is associated with lower risk.
Palomar-Cros highlights the importance of respecting these early eating patterns now that many people, seduced by the benefits of prolonged or intermittent fasting, choose to delay or skip breakfast to counteract a late dinner. "The ideal is to extend the night fast by bringing forward the last meal of the day, not postponing the first," emphasizes the ISGlobal researcher.
And it justifies that the study focused on the first and last meals of the day. "The first is important because the nocturnal fast is broken and there is increasing evidence of its importance in regulating the biological clock; and the last is relevant because if it gets late, when the body should be at rest, it causes alterations in said clock and, furthermore, since there is little interval between dinner and going to sleep, sleep and digestion are affected," he explains.
In this sense, it details that eating during the rest phase, when melatonin levels are high, can lead to developing glucose intolerance and higher blood sugar levels. "Animal studies show that delaying the first meal of the day or eating a late dinner are linked to increased body weight, fat accumulation in the liver, and alterations in gene expression related to lipid metabolism," she says.
The daily cycle of food intake alternating with periods of fasting synchronizes the circadian rhythms of the different organs of the body, thereby influencing cardiometabolic functions such as the regulation of blood pressure.
According to Palomar-Cros, from the point of view of chrononutrition, the time at which the daily eating window begins and ends and the fasting period until the next one matters most, and not so much the midday meal.
However, the researcher admits that additional scientific studies and other population cohorts are needed to confirm the potential role of meal times in disease prevention.
