How a mother's nutrition affects her baby's tastes and can adults change their eating habits

Our eating behavior depends not only on genes, but also on the influence of the external environment. For example, the nutrition of the mother during pregnancy and breastfeeding directly affects the baby's body. Even then, habits appear that will remain with an adult. Well-known neuroscientist Hanna Crichlow tells about this in the book “Science of Destiny. Why is your future more predictable than you think."

To better understand questions about the human brain and genetics, Crichlow seeks help from colleagues in other fields of science. An excerpt from the third chapter, in which the author tries to understand whether it is possible to change the habits established from childhood, Lifehacker publishes with the permission of the publishing house "Bombora".

Eating behavior isn't just about genes. Recent studies have shown that 70% of a person's body weight is determined by genes. But still, as much as 30% are due to the influence of the external environment. This means that you can either correct the deep brain circuits, or strengthen them in the first years of life, by changing the surrounding conditions. Under the influence of parental genes, the foundations of the baby's brain are laid during 40 weeks of pregnancy, including the reward system and other zones involved in appetite management. However, this can also be influenced by the intrauterine environment.

Biopsychology professor Marion Hetherington of the University of Leeds' Department of Human Nutrition Research analyzed how a mother's nutrition during pregnancy affects a child's appetite and eating habits in the future. In our conversation, she referred to the discoveries of her laboratory and scientists from all over the world, according to which there is an opportunity to reduce the potential propensity of a person to obesity.

Many of us, and especially those who have had the experience of pregnancy, have heard that the nutrition of a woman during this period plays an important role in the health of her unborn child. Pregnant women are advised to limit their caffeine intake, eliminate alcohol, and completely eliminate nicotine, any drugs and products that may contain dangerous germs, such as unpasteurized milk and cheese. Through the amniotic fluid, and then through breast milk, the mother transfers nutrients to the baby that affect the baby's rapidly developing brain.

Experiments have shown that if during pregnancy a woman ate foods high in volatile compounds, such as garlic or chili peppers, the newborn will turn and reach for the sources of these aromas. Scientists cannot yet say for sure exactly how prenatal familiarity with certain tastes affects the formation of fetal brain circuits, but it is logical to assume that the reward system plays the main role here again.

Apparently, the baby's brain is learning to associate specific smells and tastes with the mother's pleasure.

The same effect is observed in the first years of life. If a nursing woman constantly eats certain foods (in one experiment, these were caraway seeds), information about them is transmitted through breast milk. Even after many years, the child will retain a special love for this taste, which is why he will choose hummus with caraway, rather than ordinary hummus. Studies have been conducted over and over again using a variety of experimental paradigms, and collectively, they provide compelling evidence that a woman's healthy and varied diet during pregnancy and breastfeeding influences her baby's preferences, increasing the likelihood that she will eat well into adulthood.

Weaning is another opportunity to influence eating habits. The baby grows up, it's time to introduce solid food into his diet, and then there is a chance to teach him to eat vegetables, rice porridge or potatoes by adding vegetable puree to expressed breast milk. Children who have previously been given carrots and green beans will smile and are more likely to eat a large meal when they are offered these vegetables again.

I wondered if I had done enough to instill in my son a preference for lettuce over chips, and asked Marion if the baby’s taste habits could be influenced after weaning, or if this window of opportunity was closing forever.

She smiled, as if worried parents had approached her with this question more than once. The most important rule is that the sooner the better, but the opportunity to change something remains up to eight or nine years. “It's important not to give up and stay persistent. New foods, such as vegetables, will have to be offered a dozen times before the child has an association between pleasure and a particular taste. Yes, you can tap into the innate reward system and use it to your advantage."

Older children can be helped to love broccoli or other healthy foods by associating them with rewards. It is necessary for the child to associate beautiful and tasty cabbage flowers with rewards, such as a walk in the park, a favorite game, new stickers, or simple praise.

It is almost impossible for carriers of the double variation of the FTO gene to maintain a normal body weight, even if they are in constant motion.

But is it so easy to take this chance? It is difficult to imagine a woman who, due to genetic predisposition and established habits, prefers semi-finished products to vegetables and who suddenly begins to eat right during pregnancy, breastfeeding and weaning. Let's say I don't like broccoli and I have a baby. I stay awake at night and am exhausted from caring for a baby. How likely am I to buy and cook broccoli and then persuade my child to eat it if, nine times out of ten, he throws food on the floor or doesn't touch it? Outside the laboratory, early childhood environmental influences are likely to enhance rather than alter individually inherited eating habits.

“It's true,” Marion admits. - This opportunity is often missed. If you have a hereditary predisposition to being overweight, and you find yourself in a dehydrated from the English. obesogenic - prone to obesity. an environment where your parents are constantly offering you unhealthy food and are sedentary, you are sure to follow the path that inevitably leads to obesity."

Marion is trying to solve this problem. She is partnering with baby food manufacturers to develop more wholesome vegetable-based foods and promote them as the perfect food for a child who is starting to transition to solid foods. Not all parents will appreciate this, but some will still see the benefit.

It turns out that parents can influence the future of their children (but remember that you do not have to blame yourself if something did not work out for you). What about us adults who are no longer 10 years old? Is there a way to reprogram our brains so that we prefer healthy foods? Does the plasticity of our brains have the ability to change eating habits? Years of experience is difficult, but still possible to rewrite. Some people manage to lose weight and maintain a normal weight, some even become vegan or vegetarian.

Marion's findings are supported by research: it's never too late to change our behavior, but it gets harder over the years because the more our habits take root, the less we can rely on our willpower to rethink them. First of all, this is due to the fact that willpower is not a fixed moral quality, to which each of us has equal access.

Like any other character trait, the ability to resist temptations depends not only on innate neurobiological factors and environmental influences, but also on many changing conditions - for example, it is more difficult for a tired person to refrain from temptation than it is for a cheerful and full of strength. Alcoholics Anonymous uses the expression "To the White Knuckles" when referring to the willpower with which the addict resists the urge to drink every second. But this is not the best strategy for correcting any habit.

For group support and rigorous reporting, the Weightwatchers Association The Weight Watchers Association is a peer-to-peer support group for overweight people. considered the most effective route to reliable weight loss. The organization's program uses techniques that have been shown to increase the chances of continuing the diet. For example, you need to surround yourself with healthy and positive friends, attend group workouts to maintain your mood, and please yourself after going through important stages of a healthy eating system. Eat Right Now From the English. eat right - eat right; right now - right now. is a mindful eating program developed by Dr. Judson Brewer, who was an addiction specialist at Yale and later at the Universities of Massachusetts. It helped participants reduce food cravings by 40% and is now offered in conjunction with other university programs to promote healthy lifestyles.

Different people need different strategies because habit formation is a complex process that is different for everyone. This is not surprising, since it is influenced by the interaction of the following three factors: the ancient brain, which developed during the evolution of man as a species; an individual set of genes given to us from birth; the environment we are in at the moment. Therefore, if we want to change our eating behavior, we need to experiment and look for an option that suits us. There is no one-size-fits-all solution.

Evolution, epigenetics and dietary habits

A conversation with Marion convinced me that we can all, at least a little, change our eating behavior. I know that nutrition scientists are turning their attention to a new scientific field - epigenetics. But how close are they to developing therapies that can change dietary habits in adulthood? To learn more about epigenetics and its possible practical applications, I met with Professor Nabil Affara of the Pathology Department of the University of Cambridge. He studies how the external environment affects not the DNA itself, but how the body reads and uses it. In other words, the subject of his research is the expression (or expression) of genes.

Most fascinating of all is that genetic mutation manifests itself over several generations, and not on the scale of evolution.

The role of the environment in directing gene expression - epigenetic regulation - has only recently been discovered. Epigenetics helps explain why cells in an organism with the same genetic code can behave in completely different ways. Each cell of the body, based on its genetic code, creates proteins necessary for its work. Which parts of DNA are activated depends on the environment: the stomach gives the command to one cell to act accordingly, while the other receives an order from the visual organs to behave like an eye cell.

As I entered the office where Nabil works, I smelled a thick, acrid smell of burnt agar-agar. Nabil explores how the diet of parents (and even their ancestors) can affect the behavior of a person and his children. He studies the pre-conception stage by looking at how the dietary environment of sperm and eggs can alter gene expression in the next two generations.

Nutritional epigenetics was influenced by many years of research on the Dutch population, which were born at the end of World War II. Scientists have compared the health of people born in the territory occupied by German troops, where people starved in 1944-1945, and those who were born in the liberated zone and had greater access to food. It found that children whose parents ate poorly at the time of their conception were much more likely to face obesity and diabetes in adulthood.

This is due to the mismatch hypothesis. If a child grows up in a deficit environment, it is not easy for his body to get used to abundance. The point is not that the DNA of such children is rearranged under the influence of these conditions, no matter how harsh they are - the very behavior of genes changes, and this modification is passed on to the next two generations. This should be considered in our time, when there is an abundance of high-calorie, but insufficiently nutrient-rich foods.

This is another confirmation that our dietary habits are programmed not just before birth, but even before conception. Yet other epigenetic research, while far from complete, may one day lead to therapies that can help individual adults. There is growing evidence that all eating behaviors are driven by the environment our parents lived in before we conceived. In the course of one of these experiments, discoveries were obtained that can be used in the treatment of addictions. Moreover, they turned out to be so large-scale that their publication shook the entire scientific community.

Kerry Ressler, professor of psychiatry and behavioral sciences at Emory University, has studied how mice choose their food under environmental pressure. Rodents and humans have nearly the same reward systems with the nucleus accumbens, which are activated in anticipation of a tasty reward. The adjacent areas of the brain - the amygdala and the insular lobe - are associated with emotions, particularly fear. Kerry investigated the interactions between these parts of the brain.

The mice were given a sniff of acetophenone, the chemical that gives cherries a sweet scent, and at the same time shocked them with a shock. In neutral conditions, the animals sniffed and looked for sweet cherries, and their nucleus accumbens was activated in anticipation of delicious food. But time after time, the mice learned to associate the sweet smell with unpleasant sensations and froze, barely smelling it. They even began to develop new neural branches and pathways in the parts of the brain responsible for processing odors. This is due to the need to reliably anchor the new behavior. Incredibly, this acquired behavioral response was passed on to baby mice and their offspring. Subsequent generations of rodents died away at the smell of cherries, although they were never electrocuted when it appeared.

This discovery was a revelation. How is the experience gained in adulthood - the association of electric shock with the scent of cherries - inherited? In short, it's all about epigenetic modification. It turns out that the instilled fear caused genetic changes, not in the DNA itself, but in the way it was used in the mice. The settings of the receptor neurons that perceived the smell of cherries, as well as their location and number, were rearranged and fixed in the spermatozoa of mice, through which they were passed on to the next generations.

Researchers tried to associate electrical discharge with alcohol and found that alcohol deterred rather than attracted mice throughout their lives. If this discovery is true for humans, it can help explain how phobias are transmitted from person to person, even when they have never experienced triggers, and how complex behaviors can be inherited by descendants, even when they have not had the opportunity to learn it through observation.

There is growing evidence that all eating behaviors are driven by the environment our parents lived in before we conceived.

No, I'm not suggesting that you hit yourself with a weak electric shock every time you pass the bakery. Yet research suggests that our environment and genetic predisposition can be tricked into the good of future generations by altering our emotional responses and even our genetic responses to food. A promising experiment in alcohol use suggests that addictive or compulsive behavior can be overcome and thereby seriously affect the lives of millions of people.

Paradoxically, by understanding how our preferences and appetites are programmed, we can use this same mechanism to change character traits passed down from generation to generation. Epigenetics also demonstrates that evolutionary genetic changes, which take thousands of years, have an alternative, and there is a very complex connection between inherited neural connections and the environment in which we live. We are just beginning to understand how it works, and we have a long way to go to fully unleash its potential. However, given the pace of scientific progress, we have reason to hope that one day we will learn to overcome the temptation to eat a donut.

Buy the book “Science of Destiny. Why is your future more predictable than you think "

If you are interested to know how much our behavior, tastes and even the choice of friends are conditioned by the structure of the brain, then the search for answers can start with the "Science of Destiny." Crichlow and her colleagues will explain how the brain develops and learns, and whether humans have free will.