• Gut Health
  • Heart Health
    • Heart Health

      The stats tell it all: The number one cause of death in the United States is heart disease. That’s right, more than any other disease – even cancer (a close second) – heart disease is the most likely to kill you. The United States is currently facing a “diabesity” epidemic, or a substantial increase in the prevalence of metabolic syndrome leading to diabetes and obesity, all serious risk factors for heart disease.

      According to the American Heart Association, every 34 seconds someone in the US dies of a heart attack. By the time you finish reading this paragraph, another person will have lost their life. Sadly, many people do not even know they have heart disease until they experience a heart attack. These facts alone make Heart Health a critical topic to understand.

  • Skin Health
    • Skin Health

      The gut-skin connection is very significant. Inflammatory processes present in the gut may manifest on the skin. Toxins are expelled with sweat, and can cause the skin to react. Like the inside of the digestive tract, the skin is covered in microbes which can be neutral, protective or pathogenic. Skin reaction may reflect what is going on inside the body. Therefore treating skin conditions only from the outside will often be ineffective and lead to other chronic issues.

  • Brain Health
    • Brain Health

      The gut-brain connection occurs in two directions—from the brain to the gut, and from the gut to the brain. When a person has a “gut feeling,” or an emotional upset causes a stomachache or loss of appetite, they experience examples of the first, most familiar direction. When the gut is out of balance, inflammation results leading to a condition commonly known as leaky gut. A leaky gut will allow undigested food particles and toxins to enter into the bloodstream. Some may cross into the brain, setting the stage for diseases like Alzheimers and dementia. Recognizing the underlying contributing factors that created the gut imbalance in the first place is the first step to achieving optimal brain function .

  • Diet & Health
    • Diet & Health

      Healthy pH levels, whether in the colon or systemic, are found when you eat a high-fiber diet, high in vegetables and fruits, healthy proteins, and healthy fats. Complement this with foods and supplements high in beneficial bacteria, omega-3 fatty acids, and digestive enzymes, and you will be supporting optimal health (which begins in the digestive system).

  • About Brenda
  • Pet Health
    • Pet Health

      Our dog’s health is precious! They provide us with unconditional love and companionship. A daily probiotic formula is a great way to ensure good health. Make sure you choose one that delivers the recommended potency level and strain count. There is nothing quite like a healthy and happy dog. Happy Dog. Happy Life!

  • Blog
  • Shop

Probiotics – Good Summer Bugs!

Filed in Adults, Breastfeeding, Fermentation, Human Microbiome, Infancy, Obesity, Probiotics & Gut Flora, The Skinny Gut Diet, Weight Loss | Posted by Brenda Watson on 06/10/2016

probiotics - brendawatson.com

Although obesity remains one of our most pressing health problems today I’m hoping that for many Americans as the summer days unfold it may be an easier time to let go of some extra weight. In the heat, heavy foods just don’t seem quite as inviting as they were when it was cold outside. Moving around in humidity is much easier when you’re feeling lighter, and salads and light fruits are much more appealing in steamier weather. Fermented foods, which provide good bacteria known as probiotics become an excellent condiment with most any meal. Have you tried fermented salsa lately?

As always, I’m on the lookout for any new information regarding those great bacteria called probiotics. In addition to being present in fermented foods, the probiotics that we carry around inside of us also seem to impact our tendencies to accumulate weight. I found something I’d like to share with you in this article.

In my recent book Skinny Gut Diet we explored the different bacteria that have been researched thus far that play a part in whether we tend to be more fat or skinny. We actually tested our participants’ microbial ratios throughout our study and noticed that as the Bacteriodetes increased, their weight also decreased! That had also been the findings of many research studies and is mentioned in the article above. Fascinating!

Additionally, when I interviewed Rob Knight formerly of the University of Colorado and currently with the University of California, San Diego, it was clear in his studies of the Human Microbiome Project that the greater diversity of bacteria that a person’s gut environment portrayed, the more likely that person was to be healthy and balanced over all. I look forward to sharing that segment along with many more fascinating interviews with you this fall. The upcoming show is called Natural Health Breakthroughs with Brenda Watson. Keep an eye out on your local Public Television Station.

These type of studies are still in their infancy, and I’m certain much more will be learned about the actual benefits or health challenges that are directly associated with specific microbial species. Whether the research reflects obesity issues, cardiac challenges, or mental disorders, it will certainly be exciting!

What I loved reading most was research that is currently going on in Puerto Rico under the guidance of Maria Gloria Domingues-Bello of N.Y.U. It was found in previous studies that when newborns travel down the birth canal, they ingest bacteria that help them digest milk. There is a lot of evidence that babies raised on formula as opposed to breast milk are much more likely to suffer from allergies, skin conditions and even digestive issues and obesity. Babies raised on formula simply do not receive critical substances in breast milk that promote good bacteria and retard the growth of bad bacteria.

Dominguez-Bello’s new clinical trial will monitor the weight and overall health of babies born by cesarean section. These babies will be swabbed immediately with a cloth laced with the mother’s vaginal fluids and resident microbes as they come into the world. How interesting it will be to see the impact that Mom’s natural bacteria have as these children grow and develop.

I love these studies on newborns, as they are most certainly our future. However, no less important to our world is helping you to understand healthy choices that will nourish the good bacteria in your own life! And it’s easy, especially in this season to enjoy large amounts of fresh veggies and fruits along with fantastic fermented goodies. Here’s my bonus gift for you today – one of my favorite recipes! And easy to make. Happy summer probiotics to you!

Mother’s Prenatal Stress Affects Infant’s Gut Bacteria

Filed in General, Human Microbiome, Infancy, Pregnant women, Probiotics & Gut Flora, Stress | Posted by lsmith on 02/04/2015

A number of studies have linked stress during pregnancy to premature birth and low birth weight, eczema, asthma, skin condition, and general illness as well as anxiety, attention-deficit hyperactivity disorder (ADHD) and impaired cognitive and psychomotor development.1 The reasons for these associations is not completely understood. Some researchers believe that gut microbes play a role.

Intestinal microbes affect the development of an infant’s immune system, development of the gastrointestinal tract, and hormone function. Infants receive their gut microbes largely from their mother—especially if they are delivered vaginally and breastfed—and to a smaller extent from their environment. Compromised development of a healthy balance of gut bacteria during infancy can have long-lasting negative health effects.

In a recent study published in the journal Psychoneuroendocrinology, researchers found that women who experience stress during pregnancy are more likely to have babies with an imbalance of gut bacteria and worse gastrointestinal problems and allergic reactions when compared to women with less prenatal stress.1

Fifty-one mother-infant pairs were involved in the study. Stress levels during pregnancy along with salivary cortisol levels were measured. Cortisol, known as the stress hormone, is secreted under conditions of stress and so is a biological marker of stress. Those women with either high stress levels as measured by questionnaires or high cortisol levels were more likely to deliver babies with greater gut bacterial imbalance.

Fecal samples were collected up to five times beginning at seven days after birth up to four months after birth. Mothers with high stress and high cortisol levels had babies with higher amounts of Proteobacteria, which is comprised of a number of pathogenic species, and lower amounts of lactic acid bacteria (a group including the beneficial Lactobacillus) and Actinobacteria (a group including the beneficial Bifidobacterium). These children also experienced greater gastrointestinal symptoms and allergic reactions. Even breastfeeding, which is known to help promote the growth of beneficial bacteria in the gut due to its prebiotic content, was not enough to protect from the negative effects of stress.

“We think that our results point towards a possible mechanism for health problems in children of mothers who experience stress during pregnancy,” noted Carolina de Weerth, lead researcher. “Giving other bacteria would probably benefit these children’s development.”

The researchers suggest that cortisol may be affecting gut microbes in three main ways. First, cortisol may be interfering with bile production which can have an effect on gut bacteria. Second, cortisol may cross the placenta and increase fetal cortisol levels, which might affect the development of the gastrointestinal tract and impact gut bacteria. Third, cortisol may be transferred to the infant from breast milk. Cortisol is not the only mechanism, however, since prenatally stressed women without elevated cortisol also had babies with gut imbalance. The researchers suggest that the effects of stress on the endocrine and immune systems might be to blame. These mechanisms require further study.

Indeed, this study points to the need for a diet high in plant-based foods that feed the beneficial bacteria in the gut, supplementation with pre- and probiotics, and stress-reduction therapies such as meditation during pregnancy. Lactobacillus and Bifidobacterium bacteria are sensitive to environmental disturbances, and yet are well known to be crucial to the development of a healthy gut microbiota in children. Replenishing this population of bacteria—and preventing its depletion—during pregnancy, infancy, and beyond is crucial.


  1. Zijlmans MAC, Korpela K, Riksen-Walraven JM, et al., “Maternal Prenatal Stress and Infant Intestinal Microbiota.” Psyconeuroendocrinol. 2015;19 Jan: online ahead of print.

Antibiotics During Pregnancy Increase Risk for Childhood Obesity

Filed in Antibiotics, Children, Infancy, Obesity, Pregnant women, The Skinny Gut Diet | Posted by Brenda Watson on 01/12/2015

Antibiotic overuse is a problem that I discuss on a regular basis. One of the most detrimental effects of antibiotic overuse is the increase in obesity it is thought to contribute to. Dr. Smith recently blogged about the use of antibiotics during early infancy and its link to obesity later in life. A recent study published in the International Journal of Obesity adds to this research, finding that children who were exposed to antibiotics during the second or third trimester of pregnancy were at a higher risk of being obese at age seven. Infants born to mothers who delivered by Cesarean section were also at increased risk for obesity during childhood.

Of 727 mothers enrolled in the study, 436 were followed until the children reached age seven. Sixteen percent of the mothers used antibiotics during the second or third trimesters, which put them at an 84 percent increased risk for obesity compared with those children who were not exposed.

“Our findings should not discourage antibiotic use when they are medically needed, but it is important to recognize that antibiotics are currently overprescribed,” noted Noel Mueller, PhD. “Our findings provide new evidence in support of the hypothesis that Cesarean section independently contributes to the risk of childhood obesity.”

I wrote about the effects of antibiotics on the development of obesity in my latest book, The Skinny Gut Diet. Antibiotics alter the gut microbes in ways that lead to the development of obesity. Researchers are discovering that the type of bacteria you have in your gut determines whether or not you will be more likely to gain weight.

Setting up a healthy balance of gut bacteria early in life—and maintaining it throughout life—looks to be one of the best ways to avoid the weight gain trap that currently plagues two-thirds of the United States. Vaginal birth, breastfeeding, antibiotic use only when absolutely necessary, and a healthy diet rich in fruits and vegetables will go a long way toward establishing a healthy balance of gut bacteria. Probiotic supplementation can also help to support this balance.

The Immune Effects of Breastfeeding vs Bottle Feeding

Filed in Human Microbiome, Infancy | Posted by Brenda Watson on 09/29/2014

Early life events, such as mode of delivery at birth, antibiotic use, and diet, all play a big role in what bacteria develop in the intestinal tract, which, in turn, determines how healthy an individual will be. In a recent study published in the journal Science Translational Medicine, researchers from UC Davis and UC San Francisco compared breastfed and bottle-fed infant rhesus monkeys in an attempt to better understand what immune effects occur as a result of the monkeys’ diets.

They found that the breastfed monkeys had more immune cells, called memory T cells and T helper 17 cells, known for fighting certain pathogens. The differences in immune development were still present for months after weaning. Even when weaned to the same diet as bottle-fed monkeys, the improvement in immune development persisted in the breastfed monkeys.

The researchers followed six breastfed and six bottle-fed monkeys from age 5 months to one year and found that at six months, the breastfed monkeys had higher amounts of Prevotella and Ruminococcus bacteria and the bottle-fed monkeys had higher amounts of Clostridia. In addition, the breastfed monkeys had a higher diversity of gut bacteria compared to bottle-fed monkeys, a finding consistent with healthier outcomes. In general, the more diverse your gut bacteria, the healthier you are.

“Our study suggests that the gut microbiota present in early life may leave a durable imprint on the shape and capacity of the immune system, a programming of the system if you will,” noted Amir Ardeshir, PhD.

The results of this study are not surprising when you consider that up to 80 percent of your immune system resides in the gut. During early life, gut bacteria evolve and are thought to prime the immune system, teaching it how to appropriately respond. This study helps to illustrate just how this intricate relationship plays out on immune function.

Antibacterial Compounds Pose Risk During Pregnancy—How to Avoid Them

Filed in Environmental Toxins, Infancy, Pregnant women | Posted by Brenda Watson on 09/24/2014

We are a germ-fearing society. From antibacterial soaps, wipes, cleaners, and ointments to hand sanitizer and antimicrobial bedding, we are trying—literally—to wipe ourselves free of all the germs. What could all this sanitization be doing to our health, some researchers have asked? As it turns out, a lot.

One compound in particular—triclosan—is found in many everyday items such as soaps, towels, mattresses, sponges, personal care products, shower curtains, toothbrushes, phones, kitchenware, shoes, flooring, cutting boards, clothing, fabrics, and toys that are labeled “antimicrobial” or that are labeled as “odor-fighting” or “keeps food fresher, longer,” according to the Environmental Working Group.

In a recent study presented at the National Meeting & Exposition of the American Chemical Society, researchers investigated the exposure of pregnant women to triclosan and triclocarban, two of the most common antimicrobial compounds in use in everyday products.

“We found triclosan in all of the urine samples from the pregnant women that we screened,” stated Benny Pycke, PhD, one of the researchers. “We also detected it in about half of the umbilical cord blood samples we took, which means it transfers to fetuses.”

Evidence is mounting against these compounds, which have been found to lead to developmental and reproductive problems in animals and linked to health problems in humans.

“If you cut off the source of exposure, eventually triclosan and triclocarban would quickly be diluted out, but the truth is that we have universal use of these chemicals, and therefore also universal exposure,” noted Rolf Halden, PhD, lead researcher.

More than 2,000 everyday products contain these chemicals, which highlights how widespread the exposure is. Minnesota has taken offense, and has passed a ban on triclosan use in certain products that will take effect in January, 2017. Some companies are also phasing out the use of the compound, but more needs to be done to reduce our exposure. In the meantime, you can choose to buy products that do not contain these ingredients. Use EWG’s Skin Deep cosmetics database to be sure that you are buying products that don’t contain triclosan or triclocarban.

Gut Bacteria in Premature Infants Depends on Age

Filed in Human Microbiome, Infancy, Probiotics & Gut Flora | Posted by Brenda Watson on 09/22/2014

Not long ago, researchers thought that infants in the womb were free of bacteria. Infants are inoculated by bacteria during birth, and later by the environment and diet, they said, but not before birth. In 2005, that idea changed when bacteria was discovered inside the umbilical cord. Last spring, the idea was really put to death when researchers discovered that bacteria are present in the placenta. It has now become clear that even before birth, bacteria are helping to shape our health.

Although mode of birth and environmental exposures still play a big role on the community of microbes that colonize an infant, a recent study published in the Proceedings of the National Academy of Sciences journal found that, in premature infants, age also plays an important role on what bacteria are present. Researchers analyzed over 900 stool samples from 58 premature infants ranging from 23 to 33 weeks in gestational age (7 to 17 weeks premature) and weighing 3 pounds, 5 ounces or less.

They found that three major classes of bacteria colonized the infants’ guts sequentially, but in different ratios based on their age. Earliest, Bacillus bacteria dominated, followed by Gammaproteobacterium, and then Clostridium. Environmental factors such as mode of delivery or whether or not antibiotics were given did determine the pace of colonization, but not the order of progression.

Although they do not yet know the significance of these three groups of bacteria, the researchers are interested in Gammaproteobacterium due to its inflammatory properties. In healthy children, Gammaproteobacterium only make up less than one percent of the bacteria in the gut. In many of the premature infants, they made up over 50 percent, and in some infants they represented over 80 percent of total bacteria.

“It is our first glimpse of how these earliest in life bacterial colonizations—events that may have lifelong consequences—occur,” noted Phillip Tarr, MD, lead researcher.

More studies are needed to determine what relationship these bacteria have to health. Because bacteria are present in the placenta and umbilical cord, whether or not bacteria play a role in the early birth of these infants will be an area of interest to researchers.

Low-Dose Antibiotics During Early Infancy Trigger Obesity Later in Life

Filed in Infancy, Obesity, Prebiotics, Probiotics & Gut Flora | Posted by lsmith on 09/03/2014

Early life is a critical development period in many respects, and particularly as it relates to gut microbial composition. Even before birth, gut microbes are transferred from mother to fetus, a transfer that continues during birth and later via breast milk. Once established, gut microbes in the infant play a protective role on the infant’s health.

A disturbance of gut microbial balance during early development has been linked to obesity. Epidemiological studies have found that exposure to antibiotics during infancy can lead to weight gain later in life.1-3 Animal studies have confirmed this link and determined that low-dose antibiotics administered after weaning lead to an increased fat mass, altered metabolic hormones, liver metabolism, and microbiota composition.4

A recent study published in the journal Cell followed up this research and confirmed that the increased fat mass was the result of changes in gut bacteria and not to the antibiotic itself.5 Low-dose penicillin was administered either to the mother before birth and then to mouse pups until weaning, or they were administered to pups after weaning. In both cases, alterations in gut bacterial balance occurred, but they fully recovered after antibiotics were stopped. On the other hand, metabolic changes occurred that persisted into adulthood. Increased growth, which included lean mass, fat mass, bone mass, or a combination were induced by the antibiotic exposure. In addition, decreases were found in four main bacteria: Lactobacillus, Allobaculum, Rikenellaceae, and Candidatus arthromitus. Finally, a decrease in intestinal immune responses and impaired intestinal barrier function were found, which may help explain how bacteria might trigger metabolic dysfunction.

To confirm that these metabolic effects were the result of microbial alterations, the researchers transplanted feces from the obese mice into germ-free mice who inherited the altered gut microbes and went on to gain fat mass in a similar manner. They proposed the term microbe-induced obesity (MIO) as a condition of increased fat accumulation that results from alterations in gut bacteria. This study suggests that losses of the four bacteria are detrimental when they occur (Lactobacillus, Allobaculum, Rikenellaceae, and Candidatus) during the critical developmental period of early infancy.

“These four organisms have either metabolic and/or immunologic interactions, which may contribute to the observed protection from weight gain in the control animals,” noted the researchers.

“This highlights a need for judicious use of antibiotics in clinical practice in early life,” noted Martin Blaser, MD, lead researcher and author of the eye-opening book Missing Microbes. Brenda and I discuss some of his research in our new book, The Skinny Gut Diet.

Microbe-induced obesity in conjunction with diet-induced obesity (because the two go hand in hand as we discuss in our book) are a sure set up for difficult-to-lose weight gain. This was confirmed by feeding a high-fat diet to the mice given low-dose penicillin, in which they found an amplified increase in fat mass. The researchers suggest that restoration of lost microbes after antibiotic use during infancy as a potential strategy to reverse MIO and its related effects.

It is clear to me that pre- and probiotics during pregnancy will prove to be a major way to ensure that the immune system and intestinal lining of the fetus will optimally develop, which may negate the need for antibiotics, for the most part. In the event that there is a need for antibiotics, I think it will soon become standard of care to place everyone who is taking antibiotics on probiotics to maintain microbiome stability. Probiotics can provide high colony count numbers with increased species of commensal bacteria to block the emergence and dominance of pathogenic bacteria that can spell disaster.

Further studies are needed to confirm these effects in humans, and to determine what species are key to the prevention of weight gain in later life.


  1. Ajslev TA, Andersen CS, Gamborg M, et al., “Childhood overweight after establishment of the gut microbiota: the role of delivery mode, pre-pregnancy weight and early administration of antibiotics.” Int J Obes (Lond). 2011 Apr;35(4):522–9.
  2. Murphy R, Stewart AW, Braithwaite I, et al., “Antibiotic treatment during infancy and increased body mass index in boys: an international cross-sectional study.” Int J Obes (Lond). 2014 Aug;38(8):1115–9.
  3. Trasande L, Blustein J, Liu M, et al., “Infant antibiotic exposures and early-life body mass.” Int J Obes (Lond). Jan 2013; 37(1): 16–23.
  4. Cho I, Yamanishi S, Cox L, et al., “Antibiotics in early life alter the murine colonic microbiome and adiposity.” Nature. 2012 Aug 30;488(7413):621–6.
  5. Cox LM, Yamanishi S, Sohn J, et al., “Altering the intestinal microbiota during a critical developmental window has lasting metabolic consequences.” Cell. 2014 Aug 14;158(4):705–21.

Human Placenta Contains a Community of Microbes

Filed in Conditions, Human Microbiome, Infancy, Prebiotics, Pregnant women, Probiotics & Gut Flora, Urinary Tract Infections | Posted by lsmith on 06/11/2014

The human microbiome is vast, accounting for 90 percent of our cells. Microbial composition varies from site to site across a range of niches in and on the body. Some niches—such as the colon—are colonized by a very high number of microbes. Other niches—such as the stomach—are colonized by lower amount of microbes. There are yet other areas of the body that are thought to be sterile. One such site—until recently—is the placenta that develops in the uterus during pregnancy.

Previously, it was thought that a healthy placenta is free of microbes. A recent study published in the journal Science Translational Medicine found that placenta does, however, contain an array of microbes. They analyzed the placenta of 320 women who had given birth and found that 10 percent of the placenta is made up of nonpathogenic microbes from the Firmicutes, Tenericutes, Proteobacteria, Bacteroidetes, and Fusobacteria phyla, or groups of bacteria. Most interestingly, they found that the bacteria in placenta is made up of a unique community that most resembles bacteria from the mouth, which may help explain the connection between periodontal disease and preterm birth. Only one participant of the study had periodontal disease, however, so further studies will be needed to determine whether periodontal pathogens are transmitted to placenta.

The study also found that women who had urinary tract infections during early pregnancy were at higher risk of premature birth, and the infectious bacteria turned up in the placenta even when the infection was cured. The researchers are not sure whether it was the infection or if it was the antibiotic treatment of the infection that had an effect on preterm birth.

It appeared as though vaginal gut bacterial colonization, maternal obesity, or mode of delivery were not linked to the composition of placental bacteria. More studies will be needed to determine just what role these bacteria play, how they are acquired, and whether they contribute to the development of gut bacteria in the infants.

It is not a surprise to me that placenta contains bacteria. Studies have previously found that commensal bacteria exist in umbilical cord blood of healthy neonates,2 and I have long suspected that infants receive the benefit of their mother’s bacteria even before birth.  Another recent study found DNA from Lactobacillus and Bifidobacterium in the placenta of newborn infants. These studies will continue to elaborate our understanding of how microbes are an integral component to each and every phase of our lives. I would bet that women who eat a diet high in plant-based foods with pre- and probiotics as well as some fermented foods will have healthier babies with highly educated gut and immune systems trained in utero by mom’s beneficial bacteria.


  1. Aagaard K, Ma J, Antony K, et al., “The placenta harbors a unique microbiome.” Sci Transl Med. 2014 May 21;237(6):ra65.
  2. Jimenez E, Fernandez S, and Marin ML, et al. “Isolation of commensal bacteria from umbilical cord blood of healthy neonates born by cesarean section.” Curr Microbiol. 2005 Oct;51(4):270-4.

Changes in Gut Microbes of Infants Greater than We Thought

Filed in Digestive Health, General, Infancy, Probiotics & Gut Flora | Posted by lsmith on 04/16/2014

It has generally been considered that an infant’s gut microbial composition resembles that of an adult by the age of about 12 months. Gut bacterial composition during the first year of life is in flux, with great variation seen between infants and even within the same infant over time. A recent study is changing how we view the early establishment of gut microbes, however. In a recent study published in the journal Applied Environmental Microbiology, researchers determined that microbes in the infant gut continue to transform over the first three years of life.1

The infant gut microbial composition is dependent on a number of factors, including mode of delivery, antibiotic use, and diet (breastfeeding or formula feeding). It is known that vaginal birth, as well as breastfeeding, promotes the growth of beneficial Bifidobacteria—well-known to be protective of infant health, while suppressing the growth of harmful bacteria.

Most studies of infant microbial composition have focused on colonization right after birth, during weaning, or up to one year of age. In this new study, the researchers analyzed changes in gut microbiota of Danish infants between ages 9 to 18 months and from 18 to 36 months. They noted clear changes during both periods, but particular between ages 9 and 18 months.

During the period between 9 to 18 months, they observed an increase in Bacteroidetes species, consistent with the introduction of food. At the same time, they observed a decrease in the abundance of Bifidobacterium. Specifically, B. longum and B. breve decreased while B. adolescentis increased. This makes sense when you consider that B. longum, B. breve utilize prebiotics found in breast milk as food, while B. adolescentis does not. Lactobacillus species and Enterobacteriaceae also decreased during the period between 9 to 18 months, also consistent with cessation of breastfeeding and introduction to formula or cow’s milk.

Interestingly, changes continued between 18 to 36 months, suggesting that a change toward adult-like stability was still occurring during this period. This is in line with another recent study that found a similar occurrence.2 These studies are shaking up what we thought we knew about infant microbial development.

Infants who were breastfed at 9 months had higher amounts of Lactobacillus and Bifidobacterium and lower amounts of other bacteria in the Clostridium and Eubacterium taxa, changes that were still evident at 18 months, but disappeared by 36 months. The researchers also looked at physiological parameters such as measures of growth and body composition and found a correlation between duration of breast milk consumption and overall energy intake—those infants who breast fed longest had lower energy intake. They also found a link between body mass index and an increase in Firmicutes bacteria, a group of bacteria that has been linked to body fat accumulation in a number of studies.

Lastly, the researchers found considerable changes between bacterial composition during the 9 to 18 month period and again during the 18 to 36 month period. They noted two distinct enterotypes, or dominant gut bacterial types, by 36 months of age, which is in accordance with findings of two or three enterotypes in adults. The two enterotypes observed in these infants were made up of Prevotella species in one and Bacteroides species in another. These enterotypes were able to change over time, which is in contrast to findings in adults.

It would be interesting to compare the gut microbiomes of these Danish children with those of the infants in Burkina Faso Africa, where they have found bacteria in children that are non-existent in Western cultures due to dietary differences. Many of these bacteria are very good at breaking down fiber due to the high-fiber diet of this culture. In many parts of the world, children are breastfed until at least age 3 or 4. Comparing Western children to these children would help us to learn more about the benefits of breastfeeding.

More studies will be needed to better determine gut microbial changes in infants, what factors affect these changes, and how these changes relate to health outcomes. One day, we will have available bioidentical breastmilk for women unable to breast feed. Until then, probiotics during infancy may be the best bet for babies unable to be breastfed.



  1. Bergstrom A, Skov TH, Bahl MI, et al., “Establishment of intestinal microbiota during early life: A longitudinal, explorative study of a large cohort of Danish infants.” Appl Environ Microbiol. 2014 Feb 28.
  2. Yatsunenko T, Rey FE, Manary MJ, et al., “Human gut microbiome viewed across age and geography.” Nature. 2012 May 9;486(7402):222-7.

Low-Dose BPA Proves Harmful to Primates—A Model for Effects in Humans

Filed in Environmental Toxins, General, Infancy, Pregnant women | Posted by Brenda Watson on 03/28/2014

BPA is one of the most highly covered toxins by the press, and for good reason. It is one of the most widely found toxins in everyday household items such as metal food and beverage cans, plastic bottles and containers, cash register receipts, and even dental fillings. A recent primate study funded by the National Institute of Environmental Health Sciences has found that low-dose exposure to BPA alters development of infants in utero.

“Previous studies in rodents have demonstrated that maternal exposure to very low doses of BPA can significantly alter fetal development, resulting in a variety of adverse outcomes in the fetus,” noted the researchers. “Our study is one of the first to show this also happens in primates.” Why study primates? Because they closely mimic human physiology and so study results can be extrapolated to humans more accurately. What this tells us is that the case against BPA just got stronger.

The researchers found significant damage to mammary glands, ovaries, brain, uterus, lung, and heart tissues of primate infants even before birth when compared to those infants not exposed to BPA. “Our findings suggest that traditional toxicological studies likely underestimate actual human exposure and show, unequivocally, that biologically active BPA passes from the mother to the fetus,” they state.

The United States has been slow to regulate BPA, although consumers have been asking for it to be removed from certain products. BPA-free plastic products can be found, but we still have a long way to go. In the meantime, when you buy canned foods and plastic containers, purchase the BPA-free versions when possible. And if you want to be proactive, ask the stores you shop at to use BPA-free thermal receipt paper. Change like this usually begins with consumers.