You give your baby your genes. Both mom and dad contribute genes to the baby’s new genetic makeup. We’ve known this for a long time. Now we are beginning to learn more about the way those genes are turned on or off.
Epigenetics is the study of how all the switches making up our genetic material get turned “on” or “off” as our body forms in utero and then as we grow and live. These decisions about what happens and what doesn’t in a body are being made all the time, but they started being made long before you, the parents, were born.
1. What You Feel
Everyone has heard that when you’re stressed and pregnant it affects the baby. That stress isn’t good for us or our babies. The science of epidemiology goes even deeper, showing us that the effects of stress are teaching our babies’ bodies how to be a person and how to be a body. Read more on how to manage stress.
During WWII, Dutch pregnant women who were victims of the Nazi hunger winter spent months near starvation. When their babies were born, they were born expecting to live in a world without much food and their bodies had adapted to survive that. The war ended, though, and there was plenty of food. Those babies had much higher rates of diabetes, obesity, and heart disease than other generations. Their bodies were built for famine and they lived in plenty.
Imagine a baby whose mom’s pregnancy hormones were mostly happy. The baby is born expecting life to be mostly happy. Then, when born, he experiences breastfeeding, skin-to-skin, and loving care. That baby is getting a lot of oxytocin. He’s likely to have a high oxytocin threshold–he can make and use a lot of love hormones. He’ll form secure relationships, feel good about people, and generally be a happy person.
Babies who didn’t get a lot of oxytocin in utero are born expecting not much human bonding. Their body didn’t make a lot of receptors for oxytocin because, it reasoned, that would be a waste since there isn’t much around. This can be adapted throughout the first year, but researchers are arguing that these people have a comparatively lower ability to form healthy relationships and feel love.
Many of the things that build our babies we can’t control. Your stress level during pregnancy is passed down in some ways to your child. But even your stress level as a child (something you can do nothing about!) appears to impact the way your genes manifest in your children. Even mice dads who were stressed early in their life sired baby mice who were more likely to be depressed, underestimate risk, and have dysfunctional metabolisms.
Pregnant women who were traumatized by the attacks of 9-11 gave birth to children whose stress hormones and reactions to stressful situations were dysfunctional. The effects were most pronounced for mothers in their third trimester during the attacks.
People who were in abusive relationships during pregnancy have teenage children whose cortisol receptors are dysfunctional, leading to more mental health and aggression issues. A good reminder that taking care of yourself is taking care of your baby.
Genes get turned on and off our whole lives through, but especially during our time in utero and during our first year. If you had a stressful pregnancy, you can increase your affectionate behaviors now. Rat babies who were licked and cuddled by their mothers. That’s how methylation of genes changes the brain and body. Especially early on in parenting, we’re not just teaching patterns and emotions, we’re designing the genetic material of our children.
2. What You Eat
What you eat, what your parents and grandparents ate, what your parents fed you, and what you eat while your baby is growing can impact the metabolism and body composition of your children.
One study looked at the grandsons of people in a remote northern region of Sweden who were frequently starved for food. The grandsons of people who often went hungry during childhood had fewer health problems than the grandsons of those who had plenty to eat. The way we live as an effect on our children and grandchildren.
More rules about food? Ugh. Not really. Just try to eat as close to nature as you can–that’s what we have thousands of years of human history to know works. Most of the fake and processed foods are very new to our diets and science seems to be coming out against them.
And eat as much as you want! Mothers who are undernourished may give birth to children who have a genetic tendency to overeat. Numerous studies are being done to follow the nutritional choices of parents through the genes and health tendencies of their children. Too much soy, too many vitamins, too many high fat-high sugar foods…there are many ways we change the genes that are expressed in our children through what we eat.
What can you do? Don’t stress about it! Eat a whole foods diet made up of real food and as little junk as possible (more on that here). Don’t overeat any one thing– instead, use moderation in everything. The truth is we don’t know the future effects of so many things–including too much kale. You can only do what feels good to your body and try not to make food decisions based on emotions, habit or marketing.
3. How You Move
Just like movement and getting your heart rate up keeps you healthy, exercise has a protective effect on your offspring. Research shows that if your mom got sufficient exercise during pregnancy, you’re more likely to have a better metabolism and less likely to have cancer or cardiovascular risks as an adult.
4. Your Environment
We know that it’s a good idea for our health to minimize our exposure to harmful chemicals, pollution, and other hazardous elements of modern life. What we’re just beginning to learn is that our exposure may have an epidemiological effect on future generations. One study shows that pollution exposure in pregnancy may increase the asthma risk of your descendants for generations.
5. Dad is Not Off the Hook
As we’ve seen, it’s not just the body carrying the baby that informs genetic decisions regarding gene methylation. The genetic material that dad contributes also affects how your baby’s body is built and functions. Even dad’s stress levels count. Neuroscience researchers exposed male mice to high levels of stress (resulting in mouse PTSD, anxiety, and depression) and then bred them with ‘normal’ females who hadn’t been stressed. The mice babies of the stressed dads and regular moms also exhibited symptoms of anxiousness and stress. Researchers assumed the stress patterns had been handed down from the father since there was no maternal link.
In this time, when dads are able to take a more significant role in their child’s life, compared to generations past, it’s fitting that we discover just how important both parents are to making and loving a baby.
Disclaimer: Pregnancy by Design’s information is not a substitute for professional medical advice or treatment. Always ask your health care provider about any concerns you may have.
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