The most invisible umbilical cord: how much does mothers' nutrition weigh on the health of their children

Each step of the parents leaves a more or less deep mark on the path of their children.

Even before conception, their habits lead the way and, like a kind of invisible thread, this influence continues throughout childhood and adolescence.

Where they live, with whom, family income or parental education, all play a decisive role.

But also food: during pregnancy, due to the direct link through the umbilical cord of the pregnant woman, and during child-rearing, due to the replication of life patterns, among other things.

A study published this Wednesday in the

emphasizes this idea and suggests that the consumption of ultra-processed foods by mothers during their upbringing is associated with a greater risk of their offspring becoming overweight or obese.

More information

The Mediterranean diet and a relaxation program in pregnancy reduce cases of low birth weight

There is "a transgenerational association" between maternal consumption of ultra-processed foods and the body weight of their children, explains in the

a group of researchers from Harvard Medical School.

They confirm this after studying the dietary and behavioral data of a cohort of nearly 20,000 children born to more than 14,500 mothers in the United States (the data comes from the cohorts of the Nurses' Health Study II and the Growing Up Today Study).

A causality cannot be established because this study is only observational, but the analysis of the patterns of ultra-processed consumption in the mothers finds that, regardless of other lifestyle risk factors (such as smoking, marital status, education partner or physical activity), the children of women who consume more ultra-processed foods have up to 26% more risk of developing overweight or obesity than the offspring of those mothers who eat less.

By ultra-processed, scientists understand that they are products such as "bacon, colas, energy bars and ice cream that have undergone intensive industrial processing."

That is, those products that, according to the NOVA nutritional system (a food classification scale according to their level of processing), are configured as "industrial formulations" that include food substances such as sweeteners, dyes or additives, among others, to give them a certain appearance or taste or that are durable, accessible or ready to eat.

The scale is controversial within the scientific community and not all ultra-processed foods have the same impact on health, experts warn, but they do agree that many of these products tend to have a lower nutritional profile.

According to the Harvard researchers, their findings "suggest that mothers could benefit from limiting their intake of ultra-processed foods to prevent their children from becoming overweight."

"Dietary recommendations must be refined and financial and social barriers removed to improve the nutrition of women of childbearing age and reduce childhood obesity," they conclude.

The study found a link during childhood and adolescence, but, interestingly, not during pregnancy: there was a trend in the same direction, but it was not statistically significant.

The researchers believe that "maternal diet during child-rearing is likely to shape the diet and lifestyle choices" of their offspring.

In fact, they point out, it has already been shown that interventions only in the parents are also effective for the child to lose weight.

However, they leave the door open to more hypotheses that explain the persistence of this kind of invisible umbilical cord — “for example, long-term imprinting in the uterus and the presence of genes not characterized by environmental factors” — and suggest that Other avenues need to be explored further.

They also admit that part of the risk may be due to unmeasured factors.

Limit your intake

Independent experts consulted assure that the study is reliable and, despite the limitations that the authors themselves admit (such as the fact that causality cannot be established, that some data were self-reported and there may be errors, or that the results cannot be generalized because the mothers in the cohort were predominantly white), the results are “concordant” with other research.

Javier Aranceta, president of the Spanish Academy of Nutrition and of the Scientific Committee of the Spanish Society of Community Nutrition, points out that the research marks “a trend”: “There are precedents, concordant results, although they had less power.

Ultra-processed foods have a negative effect on body composition, they pose a risk of obesity, which is the zero kilometer of many diseases.

The evidence on the influence of the parents' diet on their offspring continues to grow.

At all stages.

A study in animal models found that an adverse maternal environment during pregnancy predisposes the offspring to suffer from the metabolic syndrome, with an increased risk of obesity and diabetes, and, although the causes are not clear, the researchers point to epigenetic changes in neurons of the hypothalamus, responsible for regulating the energy balance of the descendant.

Another analysis of seven European cohorts also revealed that a poor-quality maternal prenatal diet can negatively influence offspring body composition and risk of overweight and obesity.

Although the

study focuses on the role of mothers - the cohort studied was made up only of women - not all the weight falls on them.

Aranceta explains that there are already two meeting points in how the habits of parents influence the health of their children: “First, in a preconception phase, it is increasingly seen that changes in men also have an influence.

The lifestyles of the father will also influence the amount of health, in the imprint that the new being will have.

And then, in pregnancy, where the mother has exclusive influence here, metabolic programming comes into play: the fetus is going to learn from the food that the mother eats.

The imprint of flavors and smells reaches the fetus and is a way of creating passive food education”.

Influence of both parents

A scientific review published in the journal

also includes the influence of the habits of both parents, not just the mother, on the health of their children: "A higher risk of birth defects in offspring has been reported when both parents were overweight .

In addition, parental obesity before conception predicts increased offspring body mass index from childhood to adolescence and from adolescence to adulthood."

In

, scientists admit, precisely, "the possibility" that mothers are not the only ones responsible for food in the home and warn, in any case, that "it is possible that many women already feel ashamed about health behaviors related to weight during pregnancy and parenting” and reject the use of their findings “to further stigmatize their food choices.”

Fàtima Crispi, a gynecologist and researcher at BCNatal, defends that research must serve to empower women.

Crispi has proven that a Mediterranean diet intervention and relaxation techniques reduce the risk of low birth weight.

“We have never tried to stigmatize anyone.

The father's diet also has to do with it.

In this case, the most important thing is the social factor: if you get children used to seeing fresh products, legumes and healthy things in the fridge, they will see that as normal”.

And even though the

was not conclusive with the influence on pregnancy, Crispi insists that “what the mother eats affects how the fetus develops”: “There are two possible explanations [in the BMJ study]: that already, what the mother eats the mother is a reflection of what the family is going to eat;

or the biological hypothesis: what the mother eats during pregnancy, programs the child what she likes”.

The researchers do not lose focus, in any case, that the risk factors for developing obesity or overweight do not play alone, but are intertwined: it is not only the diet per se, but the greater or lesser ease of access to certain products, food education or the time available to cook and eat.

Libertad González, professor of Health Economics at Pompeu Fabra University, regrets that the Harvard researchers do not delve into the causes that explain this phenomenon, but insists, in any case, that the consumption of ultra-processed foods "is correlated with other variables, such as income or living in places where it is more difficult” to get healthy products.

There are several factors that overlap at the same time.

González also considers it a "disadvantage" that the cohort, despite being of good quality, only includes women, although she herself has led studies where, in practice, they confirm that the weight of food operations in the family falls on women. women.

Duane Mellor, a dietitian and professor at Aston University, also criticized, speaking to Science Media Center, that the

study did not include the mother's food intake at other times in her life and also "did not consider the intake food from the other parent.

In 2020, around 39 million children in the world under the age of five were obese or overweight, according to the World Health Organization.

Aranceta points out that the problem —and the responsibility— is global: “After the breastfeeding period, everyone is responsible.

We have to be responsible and parents and grandparents have to realize that we have to improve the food aspect.

The healthiest is more expensive and less comfortable, but more time in the kitchen is less time in the clinic”.

You can follow