Category Archives: Science Class

Epigenetics 102: Prenatal Nutrition and Disease Prevention

I cringe when I hear the phrase “eating for 2”.  Pregnancy is not a license to eat all of your guilty-pleasure foods as often as you want.  Pregnancy is a time when you should be extra cautious of what you put in (and on) your body.  You really only need an extra 300 calories in the second trimester and 500 calories in the third trimester, with no extra calories in the first trimester.  Instead of focusing on doubling the amount of food you eat, you should be focusing on getting the most nutrient-dense foods possible.  Doubling up on empty calories will only harm your baby.  Because what a woman is exposed to during pregnancy through her diet and environment can prevent or cause disease in her child later in life.  

How? 

By changing the baby’s epigenome.  Genes cannot be changed, but they can be turned on or off by your epigenome.  Each cell in your body has the same genes, but not all of those genes are active in every cell.  The cells in your eyes have no use for digestive enzymes (and would probably be harmed by them) so the genes that code for them are turned off in all of the cells in your eyes.  Similarly, the genes that code for photoreceptors are only needed in your eyes and are thus turned off in all other cells of your body.  How do your cells know which genes to turn on or off? That’s where your epigenome comes in.  While your genome is your complete set of DNA, your epigenome is all of the chemical compounds that control your genes.  By binding to or detaching from genes they can activate or deactivate them.  

Some genes are only active during specific periods of fetal development.  Take for example the genes that code for eye development.  These genes, and others, are active only during specific stages of fetal development, and then remain inactive for the rest of your life.  Chemical compounds turn these genes off once they have served their function to prevent you from growing a third eye.  And those genes are deactivated in the rest of your body cells right from the beginning to ensure that you don’t end up with eyes in the back of your head…or on your arms…or feet…you get the picture.  

So that is how your feet become feet and your heart becomes a heart and so on.  Because your epigenome controls which genes are turned on or off in which body part.  This is called differentiation.  Without our epigenome, we’d all be undifferentiated aliens that are not only hideous to look at but unable to function in the world.  Or even survive for that matter.  

The epigenome of a fetus or young baby can be altered by environmental chemicals in a way that increases disease susceptibility even in adulthood.   This explains why seemingly healthy people can still end up having a heart attack or getting cancer.  It was most likely programmed into their epigenome before or shortly after birth.  This doesn’t mean that eating healthy, exercising, and avoiding toxic chemicals is pointless.  An unhealthy lifestyle will only speed up disease progression and make recovery that much more difficult.  More importantly, unlike genetic changes or mutations, epigenetic alterations are reversible.  Research is showing that it is possible to make beneficial epigenetics alterations through diet and lifestyle.  So you are not doomed if you didn’t get the best nutrition in the womb or during infancy; there is still hope of changing your fate.  

Maternal stress as well as early life experiences have been linked to epigenetics changes in babies that can increase susceptibility to mental health disorders later in life.  That doesn’t mean that if you had a highly stressful pregnancy your child is doomed to become depressed or schizophrenic in adulthood.  It just means that you need to be extra mindful of providing a warm and loving environment for your child to grow up in while avoiding exposure to toxins through food and environment.  Remember, epigenetics changes are reversible.  

One of the most hopeful areas of research regarding the epigenome is the field of nutritional epigenetics.  There is potential for chemopreventive agents such as phytochemicals in food to prevent genetic diseases when administered prenatally or during early infancy by influencing the epigenome.  There is hope that even for babies who are genetically predisposed to disease, the right prenatal nutrition can alter their epigenome in a way that keeps those disease-causing genes inactive from infancy all the way through adulthood.  So perhaps the prenatal vitamins of the future will create a generation of super-babies who are immune to disease.  

My journey to a healthier, clean lifestyle started when I was pregnant with my daughter. There is no greater motivation than the daunting reality that your diet and lifestyle choices are directly responsible for the lifelong health of your precious baby.  For any of you that are pregnant or breastfeeding, please understand the importance of what you eat/drink and expose yourself to through personal care products, cleaning products, and your environment. You can either set your child up for a lifetime of good health or a lifetime of health struggles.  Your child does not have a choice, but you do.  Pregnancy is not a license to eat anything and everything.  Make healthy choices now and your child will reap the benefits for a lifetime.  

References

Kaur, P., Shorey, L. E., Ho, E., Dashwood, R. H., & Williams, D. E. (2013). The epigenome as a potential mediator of cancer and disease prevention in prenatal development. Nutrition Reviews, 71(7), 441-457. doi:10.1111/nure.12030

Sasaki, A., Vega, W. d., & McGowan, P. O. (2013). Biological embedding in mental health: An epigenomic perspective1. Biochemistry & Cell Biology, 91(1), 14-21. doi:10.1139/bcb-2012-0070

Advertisements

The Effect Of Chronic Stress On Digestion

   
What happens when you feel stressed out about something? Your sympathetic nervous system, aka the “flight or fight” response, is activated.  That means your heart rate goes up, your breathing gets heavier, adrenaline starts pumping through your bloodstream and your body diverts resources away from your digestive system while sending more resources to your brain, heart and muscles.  

Because if you’re under attack, immediate survival trumps digestion.  You need to be able to think clearly, act quickly, and either run or fight. 

But you are likely to never actually be threatened by a predator.  Because humans no longer live among wild animals. Unfortunately, your nervous system didn’t get the memo.  It still functions the same way it did back when humans were rubbing sticks together to create fire.  

We rarely face physical threats in our daily lives (at least not in first-world countries).  Nowadays we deal with more mental and emotional “threats”.  But to our nervous system, they’re both the same.  

While increased adrenaline may help us run away from an attacker, it doesn’t do much to help us with more likely stress-inducing scenarios.  Like being stuck in traffic.  Or writing a test.  Or trying to meet the next deadline at work.  Or tolerating the 10th meltdown of the day from your toddler.  You cannot run away from these “threats” nor can you punch them in the face. 

 The flight or fight response was meant to enhance our performance to deal with short term physical threats, not prolonged emotional stressors.  This is why chronic stress makes us burn out.  When your digestive system is getting short-changed constantly due to stress, it cannot do its job properly.  It cannot extract and absorb the all the nutrients your body needs to function optimally.

Which eventually leads to much bigger health problems.   You could eat the healthiest diet in the world, but if you’re too stressed out to digest it properly, it won’t keep you healthy. 

Prolonged stress can cause gastrointestinal discomfort as well as increased intestinal permeability (leaky gut syndrome)1.  So not only does chronic stress make it difficult for you to get all the nutrients from your food, it also causes your gut to absorb unwanted molecules that it would normally block from entering your bloodstream. 

So what can you do to help your digestion when you’re feeling stressed?  

1. Breathe.  Make a conscious effort to breathe slowly to calm your nerves and activate your parasympathetic nervous system which counteracts your sympathetic nervous system.  It helps you calm down and sends blood back to your digestive system so that it can function efficiently.  Do some breathing exercises just before eating, as well as afterwards. 

2.  Practice “mindful eating”.  Focus on chewing your food thoroughly, and take time to relax after eating.  Your body needs time to digest the food you just ate.  If you regularly eat on the go, scarf down your food, and take little to no time to relax after meals, then you are not getting the most out of your food.  This is definitely challenging in today’s society where 30 min lunch breaks are the norm.  But it can be done if you carefully plan out your day.  If you don’t have time to sit and relax after you eat, try to schedule the least stressful tasks on your to-do list for just after mealtimes.   Consume your biggest meal of the day when you have plenty of time to not only eat but also have some down time afterwards to allow for optimum digestion. If you are hungry and have no choice but to eat on the go, eat a small snack to tide you over and save full meals for when you have more time.  

2.  Don’t eat when you’re angry.  And don’t eat with people who tick you off.  Anger triggers your sympathetic nervous system the same way fear does.  Either eat by yourself or eat with people who make you happy. 

3.  Listen to relaxing music while you eat.  This has been proven to activate your parasympathetic nervous system1.

References

1. LABBÉ, E; et al. Coping with Stress: The Effectiveness of Different Types of Music. Applied Psychophysiology. Biofeedback. 32, 3/4, 163-168, Dec. 2007. ISSN: 10900586.

2. LI, X; et al. Combat-training increases intestinal permeability, immune activation and gastrointestinal symptoms in soldiers. Alimentary Pharmacology & Therapeutics. 37, 8, 799-809, Apr. 15, 2013. ISSN: 02692813.

The Decline of Probiotics in a Germophobic World (part 2)

   

 Ponder the above statement for a minute. What does it mean exactly? Essentially that humans are actually made up of 90% microorganisms and only about 10% human cells.

How can that be, you might ask? Because humans evolved to live symbiotically with microorganisms. We provide them with food and shelter, and they in turn help us digest components of our food that we lack the enzymes to digest ourselves. They also synthesize certain vitamins, help regulate our immune systems, and prevent invasion from harmful microorganisms that can make us sick12. Their survival is dependent on us, and our survival is dependent on them. When the balance of good germs and bad germs is thrown off, the result is termed intestinal dysbiosis1.

How do these microorganisms get inside of us in the first place?

We inherit our gut flora from our mothers. Babies in the womb are completely sterile, meaning that they have no gut flora at all3. As they pass through the birth canal they “pick up” microorganisms that are present in their mother’s vaginal tract (which is representative of the microorganisms present in her gut)9. This could be why babies that are born via cesarean section have been found to have higher rates of asthma, allergies, obesity, coeliac disease, and diabetes than babies who are born vaginally8. Recent research has also linked cesarean deliveries to an increased rate of autism but it is unsure yet as to whether c-sections raise the chances of having a child with autism or if giving birth to a baby predisposed to autism raises the chances of requiring an emergency c-section4. Babies who are born vaginally and exclusively breastfed have also been found to have more “beneficial” gut microbiota compared to babies who are born via c-section and formula-fed8.  Now that doesn’t mean that if your baby was born via cesarean he or she will be doomed to develop some sort of illness. It just means that you need to ensure your baby develops a healthy gut flora via other methods (breastfeeding, eating fermented foods, and staying away from antibiotics unless absolutely necessary).

Breastfeeding and its role in developing healthy gut flora

 Breastfeeding helps babies’ immune systems “learn” to be tolerant to different foods and things in the environment to avoid allergic reactions8. Breastmilk also contains prebiotics12 which help the probiotics in the baby’s gut flourish.  If you are unable to breastfeed there are now many probiotic formulas available to promote good gut health in your baby. Even women who breastfeed are not necessarily passing on the best probiotics to their babies unless they themselves have good gut health (although they will still pass on many other molecules that are crucial to developing healthy gut flora). Babies can be given probiotic foods when they start weaning to introduce more “good germs” into their bodies. They will also naturally pick up germs from their environment, which is good for their gut flora.  Just as long as you don’t over-sanitize everything in their environment. 

Newborns and small infants should however be kept away from sick people since their immune systems are still developing (sick people harbour pathogens, the harmful kind of microbes that you don’t want invading your baby’s body). 

What is happening to our gut health?

 The cumulative overuse of antibiotics across multiple generations is resulting in our children lacking healthy gut flora1. Add to that the negative effect that birth control pills and vaccinations have on our gut flora, and its no wonder that we seem to be getting sicker and sicker. Each generation is passing on less beneficial microbes to the next. There are scientists who are studying and saving microbes found in fecal samples from people living in the amazon and villages who have had little to no contact with the modern world and also have not contracted our modern diseases3. The hope is that some of the beneficial microbes that have gone extinct in our bodies can one day be salvaged from those people and reintroduced into our bodies to protect or even cure us of our modern diseases3. If you are interested in reading more about how and why beneficial microbes are going extinct and why they are so important, I highly recommend this book by Dr. Martin Blaser.  

What happens when we don’t have good gut health? 

The beneficial microorganisms in the gastrointestinal tract directly affect the immune system, therefore the absence of “good germs” in the gut can lead to inflammatory diseases due to a lack of regulation of the immune system11. Microorganisms in the gut also influence how a potentially toxic environmental chemical is metabolized by your body (if its absorbed or excreted)7.  Basically, good germs in your gut can protect you from bad chemicals.  Antibiotic use has even been linked to coeliac disease10  which infers that the bacteria in your gut are crucial for proper digestion of food. It is very likely that antibiotics alter gut flora to the extent of causing disease.

So what does all of this research mean?

It means that we need to be more conscious of nurturing the trillions of “good germs” in our bodies that have such a profound impact on our health. We need to be mindful that when we get vaccinated and take antibiotics or other medications, we also need to restore the good germs that may have been lost. In order to maintain optimal health we also need to maintain the health of all of our microfriends living inside of us. This is where probiotics and prebiotics come in (read more about them in my previous post here).

All of the above information DOES NOT mean that we shouldn’t get vaccinated or take antibiotics and other medications when necessary. Without them, infectious diseases would still be the number one cause of death in humans as it was prior to their invention. We just need to be aware of the effect that they have on our gut microbiota and take measures to reverse that effect. So if you get bronchitis and have to take antibiotics, follow up with a round of probiotic supplements or increase the amount of fermented foods in your diet. The same logic applies to other medications and vaccinations.

For pregnant women, probiotic foods are a must and I cannot emphasize enough the importance of maintaining a healthy gut during pregnancy. Babies who have gut dysbiosis from birth are essentially immunocompromised and will react differently to vaccinations and antibiotics or medications than babies with healthy gut flora. Any medical intervention can end up being the straw that breaks the camels back when it comes to already immunocompromised infants and children, possibly resulting in disorders like asthma, diabetes, autism, obesity, coeliac disease, and others.

Let me be perfectly clear. I am in no way saying that the above listed illnesses are caused by medical interventions. I am saying that they can be triggered by them in babies and children who are already immunocompromised due to gut dysbiosis.  Those medical interventions are necessary and can be life saving.

Think about it this way; if children with gut dysbiosis can be triggered by certain medical interventions, that’s not to say that avoiding them completely will prevent them from being triggered. Those children can also be triggered by a virus or environmental exposure to a toxic chemical, basically anything that their immune system is not equipped to handle. So avoiding medical interventions isn’t the answer, it will only delay the onset of illnesses and disorders that some children are bound to contract as long as their gut microbiota are unbalanced. The answer is to heal their immune systems by healing their guts.

Or, if possible, give them the best start in life by ensuring they are born with healthy gut flora so that they don’t need to be healed in the first place.

I wish I had known all of this when I was pregnant as I could have possibly prevented a lot of my daughter’s “gut issues” (acid reflux, gas and overall stomach discomfort, irritability, poor eating habits) that caused her to be such a fussy baby. I’m grateful that I at least know it now so I can work on balancing her gut microbiota by feeding her plenty of fermented foods. Hopefully this post will help other parents recognize their children’s gut issues. And even better, I hope it will reach expecting mothers who may have unbalanced gut flora themselves, so that they can fix the imbalance before delivery to ensure that their babies have healthy guts from birth.

There are studies that show a correlation between good gut flora and having older siblings, possibly due to daily exposure to germs from other kids. However, I have my own theory as to why children with older siblings are more likely to have healthy gut flora compared to first-born or only children:



 References:

1. Blaser, Martin J. Antibiotics Overload Is Endangering Our Children. Time.com. 5/9/2014, p1-1. 1p

2. Blaser, Martin; Bork, Peer; Fraser, Claire; Knight, Rob; Wang, Jun. The microbiome explored: recent insights and future challenges, Nature Reviews Microbiology. Mar2013, Vol. 11 Issue 3, p213-217. 5p. DOI: 10.1038/nrmicro2973

3. Blaser, Martin J. Missing Microbes: How the Overuse of Antibiotics Is Fueling Our Modern Plagues. Holt. 2014. 288p

4. Curran, E. A., O’Neill, S. M., Cryan, J. F., Kenny, L. C., Dinan, T. G., Khashan, A. S. and Kearney, P. M. (2014), Research Review: Birth by caesarean section and development of autism spectrum disorder and attention-deficit/hyperactivity disorder: a systematic review and meta-analysis. Journal of Child Psychology and Psychiatry. doi: 10.1111/jcpp.12351

5. Dong, H., Rowland, I., Tuohy, K. M., Thomas, L. V., & Yaqoob, P. (2010). Selective effects of Lactobacillus casei Shirota on T cell activation, natural killer cell activity and cytokine production. Clinical & Experimental Immunology, 161(2), 378-388. doi:10.1111/j.1365-2249.2010.04173.x

6. Dotterud, C. K.; Storr, O.; Johnsen, R.; Øien, T. Probiotics in pregnant women to prevent allergic disease: a randomized, double-blind trial. British Journal of Dermatology. Sep2010, Vol. 163 Issue 3, p616-623. 8p. DOI: 10.1111/j.1365-2133.2010.09889.x

7. Holtcamp, Wendee. Gut Check: Do Interactions between Environmental Chemicals and Intestinal Microbiota Affect Obesity and Diabetes? Environmental Health Perspectives. Mar2012, Vol. 120 Issue 3, pA123-A123. 3/5p.

8. Isolauri, Erika. Journal of Paediatrics & Child Health. Development of healthy gut microbiota early in life. Jun2012 Supplement, Vol. 48, p1-6. 6p. DOI: 10.1111/j.1440-1754.2012.02489.x

9. John Penders, MSca, Carel Thijs, MD, PhDa,b, Cornelis Vink, PhDc, Foekje F. Stelma, MD, PhDc, Bianca Snijders, MScb, Ischa Kummeling, MScb, Piet A. van den Brandt, PhDa, Ellen E. Stobberingh, PhDc. Factors Influencing the Composition of the Intestinal Microbiota in Early Infancy. PEDIATRICS Vol. 118 No. 2 August 1, 2006 pp. 511 -521 (doi: 10.1542/peds.2005-2824)

10. Mårild, Karl; Weimin Ye; Lebwohl, Benjamin; Green, Peter H. R.; Blaser, Martin J.; Card, Tim; Ludvigsson, Jonas F. Antibiotic exposure and the development of coeliac disease: a nationwide case-control study. BMC Gastroenterology. 2013, Vol. 13 Issue 1, p1-9. 9p. 1 Diagram, 2 Charts. DOI: 10.1186/1471-230X-13-109

11. Round, June L.; Mazmanian, Sarkis K. The gut microbiota shapes intestinal immune responses during health and disease. Nature Reviews Immunology. May2009, Vol. 9 Issue 5, p313-323. 11p. 3 Diagrams, 3 Charts. DOI: 10.1038/nri2515.

12. Wallace, Taylor C; Guarner, Francisco; Madsen, Karen; Cabana, Michael D; Gibson, Glenn; Hentges, Eric; Sanders, Mary Ellen. Human gut microbiota and its relationship to health and disease. Nutrition Reviews. Jul2011, Vol. 69 Issue 7, p392-403. 12p. 2 Charts. DOI: 10.1111/j.1753-4887.2011.00402.x.

Epigenetics 101: How Our Environment Affects Our Genes

Although your DNA is inherited from your parents, the environment still plays a major role in determining which genes are activated and when. Harmful chemicals in the environment can throw a wrench in your body’s genetic game plan.

(Why you should watch what you eat and expose yourself to on a daily basis )

DNA cartoon edited                                                                            IMG_3758.JPG

How do the wrong chemicals end up in your body in the first place?

1. Diet. Ingesting food or beverages containing harmful chemicals.

2. Exposure to harmful chemicals in the environment, either through inhalation or skin absorption.

Once these chemicals have entered your body, they can alter your genes in a few different ways:

1. Directly mutate a gene. This can result in an alteration of the gene’s function, complete loss of function, or no effect at all depending on the type and location of the mutation. All cells in our bodies have DNA repair mechanisms to identify and “fix” damaged or mutated DNA, however the efficiency of this mechanism varies from person to person. Just as some people have stronger immune systems and don’t get sick as often as others, some individuals have better DNA repair mechanisms and thus their bodies can handle more mutation-causing chemicals.

2. Act directly on a gene to turn it on or off. Chemicals can bind to genes in ways that can either activate or deactivate them.

3. Act on a regulatory gene that then turns another gene on or off. Many genes are part of pathways in which one gene’s product activates the next gene in the pathway and so on and so on.

Most of our DNA does not code for anything. Some genes code for proteins or RNA molecules that have some sort of perpetual function in the body. Other genes are only needed during development and are thus only turned “on” when appropriate. Certain toxic chemicals that enter our bodies can activate or deactivate genes at incorrect times. This is why exposure to chemicals is even more harmful during pregnancy. As the fetus develops, different gene pathways are turned on and off at key stages of development to ensure every part is formed correctly. Interference of the wrong chemicals (through exposure to toxins or extreme stress) or absence of the right chemicals (due to nutritional deficiencies or stress) could sabotage a certain stage of development resulting in a birth defect. There are even some genes that are only activated by extreme conditions (ex. during starvation of the body) as a survival mechanism.

Some people, although few, are lucky enough to have “good genes”. Their DNA codes for strong immune systems and highly efficient DNA repair systems. They can throw caution to the wind regarding their lifestyle choices yet still make it to old age with their health intact. However, for the majority of us, a good diet and conscientious lifestyle choices are our best shot at living out our retirement days disease-free and with our wits intact. Even those with “bad genes” (those genetically predisposed to illnesses), can change their fate by being extra conscientious of their surroundings, and of what they put both on and in their bodies.