Major depressive disorder (MDD) is the leading cause of disability in the U.S. for persons ages 15-43, affecting 16.2 million adults. Furthermore, depression is comorbid with other prevalent, chronic conditions including cardiovascular disease (CVD) and obesity/metabolic syndrome (MetS). MDD alone is almost twice as prevalent in women compared to men, and women have a 62% increase in risk for comorbidities with MDD. Comorbidity of MDD with CVD is predicted to be a primary cause of disability worldwide by 2020, posing significant public health implications for women.

A Common Mechanism of Disease

MDD, CVD, and obesity/MetS have been independently linked to changes in the body’s response to stress. Stressors, including inflammation, overnutrition, and undernutrition, stimulate a route of communication that relays information from the body to the brain. The brain responds to these challenges by sending signals resulting in behavioral and physiological changes. This communication circuit is known as the hypothalamic-pituitary-adrenal (HPA) axis and a primary signal is cortisol, the most common glucocorticoid. MDD symptoms have been linked with elevated cortisol, as a result of disease (Cushing’s syndrome) or when given as glucocorticoids. MDD affects regions of the brain that are stimulated by cortisol, sex steroid hormones, and inflammatory signals. Consequently, these regions then communicate to regulate metabolism and cardiac function. Therefore, the relationship between MDD, CVD, and obesity/MetS is not surprising from a physiological perspective.

The Role of the Prenatal Environment

Studies in both humans and rats have indicated that suboptimal conditions during pregnancy, resulting in excess maternal cortisol production and inflammation, increase the risk for MDD, CVD, and obesity/MetS in offspring. Stressful prenatal conditions include a low protein diet, high salt diet, high fat diet, and malnutrition. Prenatal stressors can impact programming of the HPA axis, resulting in long-term changes into adulthood. These changes result in hyperactivity and extension of the glucocorticoid response to stress in adults.

Why are women at greater risk?

Interestingly, the same maternal stressors produce different responses in male and female offspring. This can be partly attributed to differences in the size of regions of the brain that respond to and regulate the HPA axis. These regions are implicated in regulating mood, cardiac function, and metabolism, and are abnormal in patients with MDD. Physical differences in the anatomy of the brain are a result of differences in exposure to gonadal steroid hormones, such as testosterone and estrogen, during critical periods of development. These are characterized as permanent changes. However, short-term changes can also occur with fluctuations in gonadal steroid hormones, or in response to sex-dependent differences in circulating levels of these hormones (https://doi.org/10.1113/jphysiol.2004.078212).

These findings have widespread implications in that they suggest: 1) a shared developmental origin of multiple diseases and 2) sex dependent differences in the changes underlying diseases development. Further investigation into sex differences will be critical to the treatment of MDD comorbid with CVD and obesity/MetS in both women and men.

 

 

Folic acid is a B-vitamin and is well known for its role during early neurodevelopment. It promotes the closure of the neural tube in utero. The neural tube in the developing embryo is the first step to forming the brain and spinal cord. If the neural tube does not close, it can lead to neural tube defects (NTDs), such as spina bifida. Women of child bearing age are recommended to supplement their diet with 0.4 -1 mg of folic acid daily. Additionally, to reduce the number of NTDs mandatory folic acid fortification laws were put into place in 1998 in the US and Canada, as well as other countries around the world. In response to mandatory fortification, there has been a reduction in the number of NTDs in both Canada and the US.

Recently, maternal over supplementation of folic acid has raised some concerns.  Over supplementation is defined as ingesting over 1 mg of folic acid daily. There has been an increase in over supplementation of folic acid in the US and Canada where mandatory folic acid fortification laws are in place and supplement use is high. Epidemiological studies have reported that too much folic acid has been associated with increased risk of cancer. Interestingly, too much maternal folic acid intake has been associated with autism spectrum disorder, but the data is not clear as other studies have reported protective effects. Furthermore, too much maternal folic acid has been reported to change neurodevelopment in animals.

A recent published study investigated whether too much maternal folic acid is associated with changes in the neurodevelopment of offspring. Using a mouse model of maternal over supplementation of folic acid the authors report that male offspring from mothers that were fed high levels of folic acid had impaired memory and brain development.  The amount of folic acid in the diet of mothers was 20mg/kg to model over supplementation in humans. Animals from mothers with over supplementation of folic acid did not remember seeing a familiar object as well as control animals did. Furthermore, they had reduced levels of a neurotransmitter that is important in learning and memory called acetylcholine.

These are some of the first results showing how maternal over supplementation with folic acid may affect early neurodevelopment. We recently published an up-to-date review of how maternal over supplementation of folic acid impacts offspring neurodevelopment.  Our comprehensive analysis includes studies from human populations as well as basic science studies to understand how things in the brain as well as behaviors are changing when mothers are supplementing with too much folic acid.  More studies are required to understand the full impact of how maternal over supplementation affects offspring neurological development. As someone wise once said, everything in moderation.

 

Breastfeeding as an issue of significance in the world of public health and nutrition has gained considerable traction in recent months. With globally publicized opposition by the US to the World Health Assembly Resolution on Infant and Young Child Feeding (triggered by severe restrictions on milk products for older infants and young children) and reports of coercion to further corporate interests, the issue is of great pertinence in today’s times. It being World Breastfeeding Week, this blog will delve into the science of breastfeeding, a nutrition-focused behavior that has amassed a tremendous body of evidence in its favor when concerning infant and young child health [1].

The Lancet series published in 2016 describes both the micro and macro level benefits of breastfeeding for infants in countries of all economic strata. One paper [2] from the series estimates that approximately 823,000 annual deaths among children <5 years of age and 20,000 annual deaths of women from breast cancer can be avoided through the promotion of improved breastfeeding practices. Additionally, breastfeeding has long lasting impacts on morbidity and improves the cognitive capacity and educational potential of children, with economic benefits including higher wages in adulthood [2]. Greater benefits are achieved with longer durations of breastfeeding, and this behavior has impact on morbidity with evidence showing protective benefits against diarrhea, respiratory infections, and asthma [3].

Additionally, a growing body of evidence shows overwhelming support for breastfeeding as protective behavior against long-term health outcomes related to non-communicable diseases including obesity [3]. An analysis of 113 studies shows that longer durations of breastfeeding are associated with a 26% reduction (95% CI: 22-30) in the odds of obesity across income groups. Another pooled analysis of 11 studies showed a 35% reduction (95% CI: 14-51) in the incidence of type 2 diabetes [3]. Prior work has shown that breastfeeding confers protection against obesity later in life, with lower prevalence rates after adjusting for confounders such as socioeconomic status, birthweight and sex [4].

Recent papers published in the American Journal of Clinical Nutrition highlight the nuanced impact of breastfeeding on child growth trajectories. A study by Kramer et al. (2018) showed, using various different statistical analyses, a causal effect of randomization to a breastfeeding promotion intervention on growth during the first 2-3 months of life [5]. Additionally, these authors noted that children in a breastfeeding intervention group and those who were breastfed for ≥12 months experienced faster growth when compared to those in the control group or those breastfed for <12 months, particularly during the first 2-3 months. The differences in growth velocity between groups was lower in subsequent months and almost equalized by 12 months of age.

A study by Eny et al. conducted in Canada found that maternal BMI was positively correlated to infant BMI [6]. These authors note that maternal BMI has been shown to modify BMI growth rates among children beginning at birth up to 12 years of age [7]. These authors note that the trajectories for growth differed by breastfeeding duration, maternal BMI and birth weight from 1-3 months of age.

Results from these studies and others highlight the need for more prospective research to assess how, when and whether breastfeeding practices influence infant weight gain, and what factors within breastmilk impact lean and fat mass growth [8]. Overall, the case for early initiation, exclusivity of breastfeeding for the first 6 months and continued breastfeeding up to 2 years remain strong and programs, policies and incentives to encourage and promote adequate breastfeeding behaviors remain the need of the hour. So this World Breastfeeding Week, may mothers’ across the world be motivated, encouraged and supported to continue gifting their young one of the most valuable gifts nature has accorded us!

References:
[1] Jacobs, A. (2018). Opposition to breast-feeding resolution by the US stuns world health officials. Retrieved from: https://www.nytimes.com/2018/07/08/health/world-health-breastfeeding-ecuador-trump.html
[2] Rollins, N.C., Bhandari, N., Hajeebhoy, N., Horton, S., Lutter, C.K., Martines, J.C., Piwoz, E.G., Richter, L.M., Victora, C.G. (2016). Why invest, and what it will take to improve breastfeeding practices? Lancet, 387, 491-504.
[3] Victora, C.G., Bahl, R., Barros, A.J., Franca, G.V.A., Horton, S., Krasevec, J., Murch, S., Sankar, M.J., Walker, N., Rollins, N.C. (2016). Breastfeeding in the 21st century: epidemiology, mechanisms, and lifelong effect. Lancet, 287, 475-490.
[4] Armstrong, J., Reilly, J.J., & Child Health Information Team. (2002). Breastfeeding and lowering the risk of childhood obesity. Lancet, 359 (9322), 2003-2004.
[5] Kramer, M.S., Davies, N., Oken, E., Martin, R.M., Dahhou, M., Zhang, X., & Yang, S. (2018). Infant feeding and growth: putting the horse before the cart. American Journal of Clinical Nutrition, 107, 635-639.
[6] Eny, K.M., Anderson, L.N., Chen, Y., Lebovic, G., Pullenayegum, E., Parkin, P.C., Maguire, J.L., Birken, C.S. (2018). Breastfeeding duration, maternal body mass index, and birth weight are associated with differences in body mass index growth trajectories in early childhood. American Journal of Clinical Nutrition, 107, 584-592.
[7] Bornhorst, C., Siani, A., Russo, P., Kourides, Y., Sion, I., Molnar, D., Moreno, L.A., Rodrigues, G., Ben-Shlomo, Y., Howe, L., et al. (2016). Early life factors and inter-country heterogeneity in BMI growth trajectories of European children: the IDEFICS study. PLoS One, 2016:11:e0149268.
[8] Hay, W.W. Jr. (2018). Breastfeeding newborns and infants: some new food for thought about an old practice. American Journal of Clinical Nutrition, 107, 499-500.

Breastfeeding: Foundation of Life

World Breastfeeding Week is celebrated every year from August 1 – 7 across the globe to encourage breastfeeding and promote healthy practices from the earliest stages of life. This campaign is led by the World Alliance for Breastfeeding Action (WABA), a global network of organizations and individuals who work to promote and support breastfeeding practices worldwide. The 2018 slogan is “Breastfeeding: Foundation for Life”.

“In a world filled with inequality, crises and poverty, breastfeeding is the foundation of lifelong good health for babies and mothers.”

Latest Research on Breastfeeding

ASN’s four nutrition science journals often publish new research on breastfeeding, and there were many sessions on the topic at ASN’s annual meeting, Nutrition 2018. ASN also ensures the representation and support of breastfeeding research within our membership and scientific programs through a dedicated research interest section, Maternal, Perinatal, and Pediatric Nutrition. Members who belong to this group focus on the biology of nutrition as it impacts human development, and the role of nutrition on both short-and long-term outcomes in the mother, fetus, infant, and child.

New Research on Breastfeeding from American Journal of Clinical Nutrition

Breastfeeding newborns and infants: some new food for thought about an old practice

“Feeding newborns and infants is hardly a new topic, but these 2 articles provide some important new food for thought, and hopefully might stimulate appetite for studying how breastfeeding and human milk confer unique advantages on infant growth and development, as well as prevention of later life diseases such as obesity, which are programmed early in life.”

Breastfeeding duration, maternal body mass index, and birth weight are associated with differences in body mass index growth trajectories in early childhood

Infant feeding and growth: putting the horse before the cart

Current Knowledge on Micronutrients in Human Milk: Adequacy, Analysis, and Need for Research

This free supplement was published with the May 2018 issue of Advances in Nutrition. Articles included are:

Introduction to Current Knowledge on Micronutrients in Human Milk: Adequacy, Analysis, and Need for Research

Overview of Nutrients in Human Milk

Limitations of the Evidence Base Used to Set Recommended Nutrient Intakes for Infants and Lactating Women

Micronutrients in Human Milk: Analytical Methods

Retinol-to-Fat Ratio and Retinol Concentration in Human Milk Show Similar Time Trends and Associations with Maternal Factors at the Population Level: A Systematic Review and Meta-Analysis

Iodine in Human Milk: A Systematic Review

Vitamin B-12 in Human Milk: A Systematic Review

Breastfeeding and the Microbiome

ASN Fellow Dr. David Heber recently published a video Microbiome #3: Getting it Started. This is what he says:

“The Microbiome is established in the gut during breast feeding. While some bacteria enter the body during delivery and from the mother’s skin, the majority are formed from a special group of complex carbohydrates called Human Milk Oligosaccharides (HMO’s). There are about 150 HMO’s and they feed a single bacterial species called Bacteroides Infantilis which has a series of pumps on its surface bringing these sugars called oligosaccharides inside the cell to be digested. This bacteria is called an “inside” eater and does not share the HMO’s with other bacteria so it becomes the dominant bacteria in the gut Microbiome setting up the baby’s immune system. The breast milk has protein, fat, and lactose (the same sugar in cow’s milk) but is unique in having the 150 HMO’s. This is another reason why it is so important for women to breast feed their babies. Breastfeeding also removes 500 Calories per day from the Mom’s body helping with reducing pregnancy weight gain. During breast feeding women need to get extra protein, Calcium, vitamin D and B vitamins to replace what is being put out in breast milk!!”

Video shared with Dr. David Heber’s permission.

Mother and infant

Maternal diet during pregnancy is thought to be one of the most influential factors on child health and development. However, dietary interventions during this period may miss a critical window to improve health during childhood, as well as adult life.

In a recent series of articles in The Lancet, researchers address the significance of nutrition in the preconception period, or the time before a woman becomes pregnant. The series of three articles challenges the current perspective of the preconception period. Currently defined as 3 months before conception, the authors suggest preconception should also include any time a woman is at child bearing age. This revision is based on an understanding of the biological events occurring during the periconceptional period, or the time immediately surrounding conception. In addition, it addresses a lack of nutritional preparedness for pregnancy in women of reproductive age and the failure of dietary interventions during pregnancy in preventing adverse health outcomes.

How does pre-pregnancy nutrition affect child health?

The periconceptional period begins before fertilization occurs, with maturation of sperm and oocytes, and extends until implantation of the fertilized egg. From the time of fertilization, this process occurs relatively quickly (up to 9 days in humans) but is characterized by drastic changes developmentally, genetically, and metabolically. The embryonic genome undergoes epigenetic modifications, or alterations to the DNA that do not change the genetic code but rather affect how a gene is expressed by turning expression on or off. These modifications are responsive to environmental conditions and nutrient availability, and likely adapt to promote optimal survival under existing conditions. However, the established gene expression pattern may be detrimental in environmental conditions outside of the uterus, promoting disease development later in life.

Although epigenetic changes can occur throughout one’s lifetime, the periconceptional period is unique in that a small number of cells are present. Full exposure to the environment allows this founder population of cells to establish the genetic program that persists throughout development.

How does this change current practice?

The influence of maternal nutrition during the periconceptional period on disease and development in offspring is not a new concept. Both maternal overnutrition and obesity, as well as undernutrition have been known to adversely affect metabolic regulation in offspring and increase the risk for metabolic disease development.

More recently, analysis from the UK National Diet and Nutrition Survey suggest that less than 10% of women of reproductive age meet the recommended daily intakes during pregnancy for several key micronutrients including zinc, vitamin A, folate, and calcium. Only 30% of women meet the daily intake recommendations for iron. A lack of success of multiple micronutrient supplementation during pregnancy in improving child health outcomes, including survival, growth, body composition, and blood pressure, indicate the importance of correcting such nutritional deficiencies well before pregnancy.

These findings suggest that preconception intervention strategies should include population targeted interventions for women of reproductive age, in addition to those targeting the 3 months before conception. This will allow adequate time to correct for nutritional deficiencies before pregnancy.

Sarah Reyes, Ph.D. Candidate in Nutritional Sciences at Cornell University and NIH Predoctoral Trainee in Translational Research in Nutrition

Sarah Reyes received her B.A. in Interdisciplinary Studies – International Studies and Human Nutrition and her M.S. in Animal Science from the University of Idaho and is completing her Ph.D. studies in the Human Nutrition Program at Cornell University’s Division of Nutritional Sciences. Sarah is an NIH predoctoral trainee on a translational research in nutrition training grant of which, until recently, former ASN president Patrick Stover was the PI. Sarah has been an ASN member since 2009 and holds the position of Secretary for the International Society for Research in Human Milk and Lactation’s Trainee Interest Group, an ASN partner organization.

1. How did you first get involved in nutrition science and research?

I come from Idaho, a rural state with high rates of chronic diseases such as diabetes and hypertension. I originally wanted to become a physician because access to quality medical care in Idaho is relatively limited for poor and rural populations. I chose to study International Studies and Human Nutrition to give me breadth of knowledge that I thought would position me competitively for acceptance into medical school. However, the more I learned about the cycles of poverty and oppression in my International Studies courses and the power of nutrition and exercise to prevent and even treat chronic disease, I realized quickly that my passion was to empower people like me—the daughter of a mixed-race couple from a blue-collar family in poor, rural America—to prevent chronic disease. I became passionate about public health and how to disrupt the systems in place that sustain cycles of poverty and oppression. I recognized that my overlapping interests in basic science and public health could be a powerful tool to create evidence-based recommendations to empower disadvantaged and marginalized members of our society achieve better health outcomes. (At the time I wasn’t aware of the term translational research, but ultimately that’s what I pursued). My interest in nutrition, specifically, was inspired by my undergraduate courses which taught me that my grandmother’s type II diabetes and neuropathy were consequence of years of subsisting on a diet nearly void of fresh fruits and vegetables and eating too much white bread, white sugar, and white potatoes (I mean it was rural Idaho—yes, the stereotype applies).

2. Tell us about your current position and the research activities in which you are involved.

I’m a PhD candidate in the Division of Nutritional Sciences at Cornell University. Kathleen Rasmussen, ScD, RD is the Chair of my doctoral committee, and I collaborate with the laboratories of Anthony Hay, PhD, at Cornell University, Mark McGuire, PhD, at the University of Idaho, and Shelley McGuire, PhD at Washington State University. In the spirit of translational research, I was intent on using basic science to advance a public health initiative for my doctoral research. I was able to leverage my Chair’s interest in women’s real-life experiences with pumping and feeding expressed breast milk with the combined expertise in microbiology and lactation physiology of my collaborators. I was particularly interested in the discordance between the way expressed milk was collected in studies cited in current recommendations for handling and storage of expressed milk at home and the way expressed milk is collected in real-life. Specifically, most studies collect milk aseptically whereas real-life is messy. Women often have to pump their milk in less than ideal conditions such as in restrooms, vehicles, and other public spaces. Plus, expressed milk is often stored at multiple temperatures and poured into several different containers. My doctoral research has focused on characterizing and comparing the human milk microbiome in real-life conditions v. aseptic collection and identifying sources of and factors associated with bacterial contamination in expressed milk. We conducted a randomized trial to do this research and I’m just finishing up the analyses of this work. Our results not only fill a critical gap needed to improve existing recommendations for handling and storage of expressed milk at home, but it also opens up questions about how differential exposure to microbes from breast milk influence the infant gastrointestinal microbiome and health outcomes. I’m excited to share some of our results for the first time at Nutrition 2018!

3. You are a student at a prestigious university, a mother of two, and pregnant?! How do you do it?

I get that question a lot! In fact, I made a YouTube video of a day in my life to give others a glimpse of how I make it work. First, I have a fully supportive and loving husband, Paul Reyes. His commitment to helping me achieve this goal is undoubtedly a huge reason why I have been able to pull off school and kids simultaneously. My hat goes off to all the single, working moms out there. I don’t know how they do it! Second, having kids has pushed me to become more intentional about my goals, to prioritize my daily, weekly, monthly, and yearly tasks needed to accomplish those goals, and to manage my time so I can maintain the energy and enthusiasm needed to be productive over extended periods of time while still being present at home.

4. What do you feel are the biggest challenges facing nutrition researchers today? 

My biggest concern for nutrition researchers is public trust. Without trust, individuals will not heed recommendations. Especially where I’m from, many are leery of dietary recommendations because some have changed drastically over time (think cholesterol and eggs). Drastic changes in recommendations are perceived as “scientists don’t know what they’re doing.” Plus, policies enacted to ensure healthy eating is equitable (e.g., trans-fat bans, soda size restrictions in NYC, school lunch policies limiting access to sugary and salty foods) are seen as attacks on individual rights and freedoms, which fuels distrust in recommendations. I think a combination of the use of rigorous study methods to produce quality science along with nutrition scientists being more vocal on social and other media platforms can help improve public trust.

5. Is there anything else you’d like to tell ASN members, especially students?

Know what your objectives are and be intentional on dedicating time to those. Expose yourself to as many learning opportunities as you can to gain breadth of knowledge and experience. For example, take a short-course on equity either online, at your university, or at another university. Become involved in things that matter to you both professionally and personally! This will keep you enthusiastic and motivated about your research and help you live a healthier life. Stay open-minded and remain objective in your pursuit of science. Finally, find a good mentor and a good advocate. A good mentor will help you learn how to conduct rigorous science and sharpen the skills you need to meet your own personal objectives. An advocate is someone who is respected in your field that can help you find and avail on opportunities that will help you achieve your goals.

[Learn more about ASN student membership here]

Sarah Reyes’ primary interests are the developmental origins of health and disease and finding equitable solutions to empower disadvantaged and marginalized populations achieve better health outcomes. Sarah’s interests are focused on the mother-infant dyad and, in particular, the breastfeeding relationship. Most recently, Sarah’s work has focused on characterizing the bacterial communities in breast milk pumped in real-life conditions. Sarah has conducted research in mammalian and bacterial cell culture, biochemical analyses, epidemiology, and microbiome research. In addition to her research interests, Sarah is interested in opportunities to use her knowledge to serve others. She recently attended the Make the Breast Pump Not Suck Hackathon where she helped design a study to evaluate the efficacy of hand expression on milk volume for incarcerated women in New Mexico. Visit her video, A Day in the Life of a PhD Mom | Ivy League, Kids, and Pregnancy.

These days you can hardly watch a T.V. program without being bombarded by the newest diet craze. Maybe it’s the time of year, January, when everyone is hoping to make 2018 their year, but more likely it is because dieting has become a multi-billion-dollar industry in the United States.

 

As a new-ish mother I’ve been carrying around the last 5, 10, okay 15 pounds for the last 7 months and decided in a sleep deprived haze to attempt a weight loss intervention for 2018. I was immediately overwhelmed by the number of programs, quick fixes, and suspicious non-FDA approved ‘supplements’ floating around on the market.

 

While all of these diets certainly have their individual gimmicks, they center around the core idea of calories in vs calories out. This core tenant of weight loss has been recognized as the hallmark of successful lifestyle change, that is, to lose weight one must intake less energy than they expend. While there are multiple ways to achieve this negative energy balance (i.e. diet, exercise, weight loss surgery, pharmaceuticals, etc.) I was interested in how to achieve negative balance while retaining a healthy breastmilk supply.

 

Breastmilk is composed of the 3 major macronutrients: fat, protein, and carbohydrate. Of these, mature breastmilk (that produced around day 6), contains 3.5 g of fat, 7 g of carbohydrate, and 0.9 g protein per 100ml. It also contains a whole host of other vitamins, minerals, immunoglobulins, and bioactive factors (1).  Most of the papers examining breastmilk composition in well controlled studies focus on diversity and amount of specific Fatty Acids, total protein profile, and total energy content (2). Multiple studies have also focused on the amount of DHA passed in breastmilk and linked it to maternal consumption of fatty fish (2).

 

While the outcomes of these studies showed associations of maternal diet with breastmilk composition only one well controlled study has been done to address the effects of following a diet (low carbohydrate or low fat) on the composition and supply of breastmilk. This study found that under moderate caloric restriction women on a ‘low’ (~31%) carbohydrate diets (vs low fat diets ~26% fat) had higher levels of fat in their breastmilk with higher levels of energy expenditure. Neither diet impacted breastmilk production as both were only moderately hypocaloric (3).

So where does that leave us?

 

We know women are likely to gain and retain weight during a first pregnancy putting them at higher risk for complications should a second pregnancy be desired. It appears that the most important time for weight loss interventions is the first 18 months post-partum after which weight loss tends to plateau (4). With the importance of exclusively breastfeeding up to a year we need more studies that focus on effective weight loss techniques for post-partum women who wish to maintain milk supply.

 

As for me? I think I’ll cut out the bread and leave the butter.

 

 

 

 

1) World Health Organization. “Infant and young child feeding: model chapter for textbooks for medical students and allied health professionals.” (2009).

 

2) Bravi, Francesca, et al. “Impact of maternal nutrition on breast-milk composition: a systematic review, 2.” The American journal of clinical nutrition 104.3 (2016): 646-662.

 

3) Mohammad, Mahmoud A., Agneta L. Sunehag, and Morey W. Haymond. “Effect of dietary macronutrient composition under moderate hypocaloric intake on maternal adaptation during lactation–.” The American journal of clinical nutrition 89.6 (2009): 1821-1827.

 

4) Gunderson, Erica P. “Childbearing and obesity in women: weight before, during, and after pregnancy.” Obstetrics and Gynecology Clinics 36.2 (2009): 317-332.

Potential mothers, new mothers and mothers of multiples often worry about how their nutrition will affect their children. With the high rates of childhood obesity, some mothers worry more than ever about what they are putting in their bodies. Although this could be a discussion that includes pesticides on food, chemicals in cleaners and even air pollution, let’s just focus on nutrition.

 

It has been shown that a strong predictor of a child’s future BMI is the mother’s pre-pregnancy BMI (Schou-Anderson et al, 2012). This prediction comes from two sources, environment (how parents eat directly influences how children eat) and genetics (especially epigenetics). Epigenetics is how our cells control gene expression without changing the core DNA sequence and can include both DNA methylation and histone modification. It is consistently reported that maternal diet can directly alter DNA binding sites (Aagaard-Tillery et al, 2008) and DNA methylation (Dudley et al, 2011) in the offspring of mothers fed high fat diets. High fat diets contain energy dense foods consisting of >45% of total calories from fat, essentially mirroring the typical Western diet, which is full of highly palatable, highly processed energy dense foods. While this is certainly not a comprehensive list of publications on this topic, it is safe to say that maternal diet can influence an offspring’s risk of developing obesity through epigenetics (a nice review here). Hence the idea that whatever you eat, your baby also experiences.

 

While this may not be a novel concept, it is more important than ever to educate mothers (and fathers!) about the influence their diet could have on their future children’s body composition and their overall risk for obesity-associated diseases. While this information may initially leave parents anxiously asking questions like “Is there anything I can do?!”; “Is the damage already done?”; or “What could I have done differently?”, our goal is to provide information that is both reassuring and accurate knowing that with the right nutritional decisions, your child will be just fine!

 

Multiple studies have shown interventions in eating patterns and exercise work for reducing obesity and risk for associated diseases (reviewed here, here, here, here, here etc.).

 

The trick? Implementing these changes in your families diet and exercise routines to change the trajectory that epigenetics may have imposed when your little one was no larger than a grain of rice.

 

As a new parent you can go no longer than 24 hours without hearing the phrase “Breast is Best.” I know this to be true because I became a parent in June of this year. In the hospital we were offered consults with lactation and had no less than six posters in our room touting the benefits of breastfeeding. As a PhD student I was intrigued by the literature behind these recommendations and eagerly spent multiple late night nursing sessions on my iPad reading the latest research. What I found were some studies finding associations with reduced risk of obesity, and others failing to find this same association (literature). Overall, it was concluded in the previous review that breastfeeding was associated with a reduced risk of obesity.

While this was great news, I could not help but question; was this association because of breastmilk or mode of delivery? Bottle feeding is typically associated with formula feeding but a growing number of women have begun pumping their breastmilk after returning to work or in cases of pre-term birth and latch issues.

Could bottle feeding breastmilk still ameliorate the risk of obesity later in life?

I was not the first person to raise this question which has been addressed here, here, here, and here. Overall the consensus seems to be that early bottle feeding, of breastmilk or formula, is associated with an increased risk for excess weight gain and poor self regulation. Exclusively feeding expressed milk is also associated with early cessation of breast-milk feeding.

So this leads to the inevitable question; what is a mother to do?

While the literature is still unclear if bottled breastmilk can fight obesity risk, it is clear the breastmilk has multiple other benefits according to the American Academy of Pediatrics and should be offered when possible. So to those mothers who pump a little, a lot, or all the time, I say pump on ladies!

For many generations parenting books and gurus alike have heralded the importance of routine. Beginning in infancy, children are scheduled to eat, sleep and play, and busy moms often follow this schedule to assure their youngest children are happy, healthy and well socialized. But, as is always the case, children grow older and become involved in more activities making it difficult to stick with rigid schedules established in infancy.

Recent evidence however has shown that regular mealtimes, bedtimes and limits on television at age 3 were all linked to children having better emotional self-regulation later in life. Self-regulation has two distinct domains, emotional and cognitive. Together, these domains help children control their attention. While these two domains have traditionally been studied together it is important to examine them independently as emotional self-regulation is tied to subcortical structures in the brain while cognitive self-regulation is based in the prefrontal cortex. The prefrontal cortex is known to mature later in development continuing its maturity until the early 20’s so outcomes based on these two domains must be distinct.

Anderson and colleagues (2017) tackled these questions in their recent publication accepted in the Journal of Obesity. Using a prospective study they examined how both domains of self-regulation and routine can impact obesity later in childhood (although only until age 11). The Millennium Cohort Study gathered data from 19,244 families recruited in the UK from 2000-2002. Data was collected beginning at 9 months with follow-ups at ages 3, 5, 7 and 11. Child Social Behavior Questionnaires were used at age 3 to determine self-regulation, while height/weight was used at age 11 to determine BMI and obesity status. A series of logistic regressions were used to understand how self-regulation and routine related to risk for obesity at age 11.

Results showed that having a “sometimes-regular bedtime” or “inconsistent bedtimes” were both associated with elevated risk for obesity at age 11. High television/video viewing time was initially associated with higher obesity rates but the result was not significant after controlling for other routines, a result that could be explained by the imprecise measurements used to quantify time spent. Surprisingly, children with mealtimes that varied considerably were found to be less likely to be obese at age 11. While this study agrees with previous literature in terms of bedtime, the results for mealtime were unexpected and need to be considered in the context of the study which was observational and based on parent self-report. Overall, emotional self-regulation and household routines were independent predictors of obesity at age 11 and those children with regular bedtimes, mealtimes, and limits on television/video displayed enhanced emotional self-regulation.

While this study demonstrates the importance of routine, it is important to understand that many factors could not be controlled for, leaving the study with multiple limitations. Still, if putting the kids to bed at the same time could be protective, maybe those rigid schedules shouldn’t be abandoned just yet.

 

References:

Anderson, S. E., et al. “Self-regulation and household routines at age three and obesity at age eleven: Longitudinal analysis of the UK Millennium cohort study.” International journal of obesity (2005) (2017).

Sowell, Elizabeth R., et al. “Mapping cortical change across the human life span.” Nature neuroscience 6.3 (2003): 309-315.