Chrononutrition argues that eating late and skipping breakfast is unhealthy8 min read
A Spanish researcher who is an expert in chrononutrition has gone one step further and has shown that it is not only important to take into account what and how much we eat, but also when.
A study funded by the US National Institute of Health and conducted by researcher Marta Garaulet Aza confirmed that eating late increases the risk of diabetes in 50% of the population due to a genetic variant.
It was found that eating late affects glucose tolerance, especially in those who have a risk genetic variant in the melatonin receptor; specifically in the MTNR1B variant that is present in half of the population of Spain.
This is something really important, especially since a genetic variant has been determined that increases the risk of type 2 diabetes in half the population”, “Thanks to this research we have managed to establish the relationship between the functioning of insulin in the pancreas and melatonin.
On 2 different days, the researchers monitored glucose tolerance and insulin secretion. A glucose tolerance curve was performed in the first session, after taking a dextrose serum 4 hours before their usual bedtime. In the second session, glucose solution was ingested one hour before the volunteers’ usual bedtime.
The research also included monitoring and recording the eating and sleeping habits of the participants for a week.
Previous studies had identified that the melatonin receptor is a gene implicated in diabetes, that shift workers are at increased risk of developing type 2 diabetes, and that taking melatonin regularly increases blood sugar levels.
The new discoveries are an extremely important focus because they apply to about one-third of the population in the industrialized world, who consume food close to bedtime.
Italians eat dinner about an hour earlier, around 8:45 p.m., while Germans eat their last meal of the day at 7:00 p.m. and Swedes at 6:00 p.m. The implications for countries with late eating habits such as Spain are considerable since the average dinner time of a Spanish family is approximately 9:45 p.m.
The appropriate thing would be for the Spaniards to advance their dinner a little, at least, at the time of the Italians. For various reasons, 75% of the population should not eat late.
In previous research, eating late was associated with lower energy expenditure, decreased carbohydrate oxidation, altered diurnal temperature rhythms, increased carbohydrate intolerance, which may be a marker of circadian health, and altered sleep rhythms. cortisol, which is known to be typical of stressful situations.
The study establishes that by altering eating times to eat later for a week, healthy thin women had similar physiological behavior to obese or elderly women.
The recent findings about the risk of diabetes in people who eat late are not surprising to Garaulet, who has been warning for years that the ancient Spanish tradition of dining around 10 pm can be harmful to health.
Garaulet carefully explained the importance of understanding our biological clocks to improve our level of well-being. She was the first to show that there is a clock in adipose tissue and that knowing what and how to eat is not enough, but also when.
Explain that living things have biological clocks that are synchronized by the environment.
The Swedish botanist Carlos von Linnaeus was one of the first to understand this phenomenon, to whom we also owe the nomenclature and classification of the species. He claimed that “nature did not jump” and that everything happened in a specific order. He verified this with his Floral Clock, in which he represented the maximum opening hours of the flowers. He knew that each species of flower responded differently to the sun’s rays.
In 1885 Leonard Landois, a German physiologist, described that the body does not work like a machine in a uniform way, but that human physiology changes throughout the day because we have gradual changes in our body temperature. If we go to bed at midnight and wake up at 8:30 a.m., we will have the highest level of alertness at 10 a.m. and at 3 p.m. the energy level usually drops.
This was the first clue, which would take more than 100 years to prove, to explain that the need to take a nap is a physiological and not a cultural fact.
The rationale for these changes lies in circadian rhythms, which are physical, mental, and behavioral changes that follow a 24-hour cycle. Most living things are largely responsive to and affected by these natural processes, including animals, plants, and microbes. Activity changes in animals are an example of a light-related circadian rhythm. Humans are diurnal mammals that are conditioned to sleep at night and be awake during the day.
These circadian rhythms are coordinated by the suprachiasmatic nucleus or SCN, which is a group of about 20,000 neurons found in the hypothalamus that serve as the body’s central clock. But that clock does not work independently but rather is synchronized to the changes it perceives in the environment.
The rhythm of hormones
Furthermore, it has been scientifically proven that hormones have their own rhythms.
Growth hormone is elevated during the night hours and that is why it is said that children grow while they sleep. The secretion of leptin, which is the hormone that regulates hunger, is high at night because if we were hungry at dawn we would not be able to sleep. While cortisol can increase up to six times in the morning and that allows us to start the day with energy.
Depending on the time of day, another hormone that changes radically is insulin, allowing sugar to pass from the blood and enter the tissues. At 9 am we have a good secretion of insulin, in the afternoon (and if we eat sweets) the insulin does not respond as well and at night the production of insulin is low.
But organs and arteries also have their own clocks, called peripheral clocks, which coordinate with the central clock. In addition to light and dark, peripheral clocks detect when you eat or stop eating and when you move. In normal situations, these clocks associate that the night is for resting and fasting and the day is for eating and being active.
The nutrigenetics of Ordovas
Nutrigenetics is the interaction of the various genetic variants and what we ingest in our body.
Garaulet argues that we are born and die with the same genetic code and there is no way to alter it. Obesity only occurs when a person with a genetic predisposition consumes a high-fat diet. So although we cannot change the genetic constitution, we can change our habits so that the risk genes are not expressed.
Nutrigenetics is a science with practical applications because it allows the design of a specific nutritional plan so that it interacts with the genetic constitution of each individual and achieves optimal health.
José María Ordovas, one of the fathers of nutrigenetics, found that 90% of people who consume a lot of fat gain weight for genetic reasons.
In the DNA of all people there are four nucleotides or bases: adenine (A), cytosine (C), guanine (G) and thymine (T). Ordovas analyzed that people who gain weight by eating fat have a thymine in a specific position in the ApoA5 gene. But there are 10% of people who do not observe a change in weight when they eat fat because instead of a thymine it has a cytosine.
Garaulet obtained the same results when replicating the study in a thousand Spanish patients.
However, the researcher went further and measured the level of triglycerides in the blood of the patients and found that the minority group not only does not gain weight but that the more fat they eat, the less triglycerides they have in their blood, that is, they are protected from the risk cardiovascular.
Other studies that invite you to dinner early
It is fashionable to talk about the glycemic index, says Garaulet, it is the ability of a food to raise blood sugar in the two hours following its consumption.
Certain foods such as cakes, cookies, ice cream, white bread have a glycemic index of almost 100%. But there are other foods such as some types of rice or vegetables, or whole-grain breads that lower the glycemic index by almost half.
Garaulet assures that what is truly fascinating is that it is not an absolute or radical concept because they have discovered that the glycemic index changes depending on the time of day.
A Galician stew does not have the same effect if it is eaten at 1:00 pm or 4:00 pm.
Garaulet demonstrated, together with the researcher Cristina Bandín in 2015, that a stew caused changes in carbohydrate metabolism and glucose tolerance depending on the time.
It was found in a study that the time of food consumption affects glucose tolerance. People who ate a light breakfast and a heavier lunch had greater glucose intolerance and more trouble metabolizing carbohydrates.
In another experiment, the same dinner, some ravioli with tomato and a peach in syrup, was given to 40 women. Some ate an early dinner at 7:00 p.m. (which is 4 hours before their usual bedtime) and others a late dinner between 10:30 p.m. and 11:00 p.m. (one hour before their usual bedtime).
It was concluded in this preliminary study that eating late dinner produces a decrease in glucose tolerance, compared to those who eat early.
Another component that leads to obesity are perilipins, proteins that surround the drop of fat that is inside the adipocytes, and that prevent the mobilization of that fat. If the perilipins work well, we will have difficulty losing weight and this happens in 90% of the population.
The proper functioning of perilipins was an evolutionary advantage centuries ago, because humans needed to maintain the effect of food in the body for a longer time. Those who stored fat were more likely to survive famines.
10% of the population that have less efficient perilipins and that allows them to better mobilize fat. Those people always stay slim because they have no problem losing weight, even if they eat late. And although in prehistory these people had more difficulty staying alive, in the modern era with a tendency to obesity, their weakness has become a strength because it reduces their risk of suffering from cardiovascular diseases.
Garaulet also suggests, based on another essay, that eating breakfast is healthy because he related skipping breakfast to a higher body mass index, a tendency to depression and the habit of smoking.
It is clearly concluded with the analysis of all the studies questioned, that genetics and eating habits are decisive factors to maintain a healthy weight.
If you really want to stay healthy, have a balanced diet for breakfast, lunch and dinner early. Posted by Iraq.info, news and information agency