Skip to content

Category: nutrition

Published on

Heavy alcohol consumption has been linked to increased risk of several cancers (colorectum, breast, oral , pharynx, larynx, liver, and esophagus). But what about moderate or minimal drinking? The Mediterranean diet and other studies looking at longevity have long viewed a glass of wine a day as beneficial. However, this large study found that even light to moderate drinking is associated with an increased risk of breast cancer in women, and there is an increased risk of alcohol related cancers only among male smokers. From Science Daily:

Light/moderate drinking linked to increased risk of some cancers in women, male smokers

Even light and moderate drinking (up to one drink a day for women and up to two drinks a day for men) is associated with an increased risk of certain alcohol related cancers in women and male smokers, suggests a large study. Overall, light to moderate drinking was associated with minimally increased risk of total cancer in both men and women.

However, among women, light to moderate drinking (up to one drink per day) was associated with an increased risk of alcohol related cancer, mainly breast cancer. Risk of alcohol related cancers was also higher among light and moderate drinking men (up to two drinks per day), but only in those who had ever smoked. No association was found in men who had never smoked.

They used data from two large US studies that tracked the health of 88,084 women and 47,881 men for up to 30 years. They assessed risk of total cancer as well as known alcohol related cancers including cancer of the the colorectum, female breast, liver, oral cavity, pharynx, larynx and esophagus.

Light to moderate drinking was defined as up to one standard drink or 15 g alcohol per day for women and up to two standard drinks or 30 g alcohol per day for men. One standard drink is roughly equivalent to a small (118 ml) glass of wine or a 355 ml bottle of beer....During the follow-up period, a total of 19,269 and 7,571 cancers were diagnosed in women and men, respectively. The researchers found that overall, light to moderate drinking was associated with a small but non-significant increased risk of total cancer in both men and women, regardless of smoking history.

Published on

 Artificial trans fats in foods are bad for health in so many ways: linked to increased risk of coronary heart disease, atherosclerosis, inflammation, and risk of early death. And even though the FDA is finally phasing out partially hydrogenated oils (because they have high levels of artificial trans fats) within the next 3 years, trans fats will still be found in foods (processed foods). How can this be? Well, trans fats are still allowed to be in foods that are labeled as 0 trans fats if it is less than .5 grams trans fats per serving (a loophole allows them to round downward to zero ). And according to research by Environmental Working Group (EWG), trans fats are being used by the food industry in undisclosed ways in amounts low enough to exploit the trans fat loophole. Besides partially hydrogenated oils, they are found in other types of refined oils, monoglycerides, diglycerides and other emulsifiers, and even in flavors and colors. So when you see ZERO trans fats on the label, it doesn't actually mean that it is zero trans fats. The problem is that over the course of a day, eating a number of foods and servings that have under .5 grams of trans fats adds up to levels that research now says has negative health effects!

Artificial trans fats are found in a lot of processed foods. A EWG analysis found that harmful artificial trans fatty acids lurk in more than 27 percent of more than 84,000 processed foods common in American supermarkets.  Another 10 percent contain ingredients likely to contain trans fat. Foods most likely to have hidden trans fats are: breakfast bars, granola and trail mix bars, pretzels, peanut butter, crackers, breads, kids fruit snacks, kids cereal, graham crackers, whipped topping, non-dairy creamers, pudding mixes, cupcakes, and ice cream cones.

So what can you do? Read ingredient lists on labels and try to avoid foods with the above mentioned ingredients: partially hydrogenated oils, emulsifiers, monoglycerides, diglycerides and other emulsifiers, artificial flavors, artificial flavors, and colors. Try to cut back or avoid foods that have ingredients that are not real foods - tough to do, but it can be done.

And the amazing part, saturated fats (such as butter) are NOT linked to early death and heart disease, but trans fat in foods is. Latest research, from Science Daily:

Trans fats, but not saturated fats like butter, linked to greater risk of early death and heart disease

A study led by researchers at McMaster University has found that that trans fats are associated with greater risk of death and coronary heart disease, but saturated fats are not associated with an increased risk of death, heart disease, stroke, or Type 2 diabetes. The findings were published today by the British Medical Journal (BMJ)...."For years everyone has been advised to cut out fats. Trans fats have no health benefits and pose a significant risk for heart disease, but the case for saturated fat is less clear," said de Souza.

Saturated fats come mainly from animal products, such as butter, cows' milk, meat, salmon and egg yolks, and some plant products such as chocolate and palm oils. Trans unsaturated fats (trans fats) are mainly produced industrially from plant oils (a process known as hydrogenation) for use in margarine, snack foods and packaged baked goods.

Contrary to prevailing dietary advice, a recent evidence review found no excess cardiovascular risk associated with intake of saturated fat. In contrast, research suggests that industrial trans fats may increase the risk of coronary heart disease.

To help clarify these controversies, de Souza and colleagues analysed the results of 50 observational studies assessing the association between saturated and/or trans fats and health outcomes in adults....The team found no clear association between higher intake of saturated fats and death for any reason, coronary heart disease (CHD), cardiovascular disease (CVD), ischemic stroke or type 2 diabetes. However, consumption of industrial trans fats was associated with a 34 per cent increase in death for any reason, a 28 per cent increased risk of CHD mortality, and a 21 per cent increase in the risk of CHD.

Inconsistencies in the studies analysed meant that the researchers could not confirm an association between trans fats and type 2 diabetes. And, they found no clear association between trans fats and ischemic stroke. The researchers stress that their results are based on observational studies, so no definitive conclusions can be drawn about cause and effect.

Published on

Trans fats are commonly used in processed foods to improve taste, texture, and shelf life. Artificial trans fats are found in partially hydrogenated oils and in other ingredients, such as refined oils, emulsifiers, flavors and colors. Even those processed foods that say zero trans fats may contain trans fats - due to a loophole in labeling laws (if it has less than .5 grams per serving, then it can be rounded down to zero - thus allowing the incorrect claim of zero trans fats). Eating a variety of processed foods, each containing a little trans fats, easily adds up to eating a significant amount daily.Trans fats in the diet have long been linked to cardiovascular disease, artherosclerosis, obesity, oxidative stress, and inflammation, but now research finds that it is linked to a poorer memory in middle-aged men under the age of 45. From Science Daily:

Dietary trans fat linked to worse memory

Higher consumption of dietary trans fatty acids (dTFA), commonly used in processed foods to improve taste, texture and durability, has been linked to worsened memory function in men 45 years old and younger, according to a study.

Researchers evaluated data from 1,018 men and women who were asked to complete a dietary survey and memory test involving word recall. On average, men aged 45 and younger recalled 86 words; however, for each additional gram of trans fats consumed daily, performance dropped by 0.76 words. This translates to an expected 12 fewer words recalled by young men with dTFA intake levels matching the highest observed in the study, compared to otherwise similar men consuming no trans fats.

After adjusting for age, exercise, education, ethnicity and mood, the link between higher dTFA and poorer memory was maintained in men 45 and younger.The study focused predominantly on men because of a small number of women in this age group. However, including women in the analysis did not change the finding, said Golomb. An association of dTFA to word memory was not observed in older populations. Golomb said this is likely due to dietary effects showing more clearly in younger adults. Insults and injuries to the brain accrue with age and add variability to memory scores that can swamp ability to detect diet effects.

Trans fatty acids have been linked to negative effects on lipid profiles, metabolic function, insulin resistance, inflammation and cardiac and general health. In 2013, the United States Food and Drug Administration issued a preliminary determination that trans fats were no longer generally recognized as safe. According to the Centers for Disease Control, reducing dTFA consumption could prevent 10,000 to 20,000 heart attacks and 3,000 to 7,000 coronary heart disease deaths per year in the U.S.

Published on

Beware of big soda companies bearing gifts to scientists and their misleading messages to consumers. This time it is Coca-Cola that is trying to influence the research by funding scientists who shift blame for obesity to lack of exercise.There is a large body of evidence finding that what you eat is very important for health and weight control, and this does not mean a diet filled with highly processed foods, including soda.

Yes, exercise is important, but the overall diet is even more important. And we know that soda is not a beneficial food for the beneficial microbes within us (Feeding Your Gut Microbes). Coca Cola's sales of soda are really slipping and this Global Energy Balance Network is a major effort on their part to try to boost sales of sugary drinks. From NY Times:

Coca-Cola Funds Scientists Who Shift Blame for Obesity Away From Bad Diets

Coca-Cola, the world’s largest producer of sugary beverages, is backing a new “science-based” solution to the obesity crisis: To maintain a healthy weight, get more exercise and worry less about cutting calories.The beverage giant has teamed up with influential scientists who are advancing this message in medical journals, at conferences and through social media. To help the scientists get the word out, Coke has provided financial and logistical support to a new nonprofit organization called the Global Energy Balance Network, which promotes the argument that weight-conscious Americans are overly fixated on how much they eat and drink while not paying enough attention to exercise.  ...continue reading "Ignore Big Soda’s Message"

Published on

Another study finds health benefits to eating a Mediterranean based diet (here combined with the DASH diet) - the MIND diet. The researchers found that the older adults who followed the diet best were about 7.5 years younger cognitively than those who followed it least, thus suggesting that it may slow the cognitive decline of aging. Earlier research had suggested that it may reduce a person's risk in developing Alzheimer's disease. Foods to eat: fruits, vegetables, berries, whole grains, legumes (beans), nuts, fish, a little wine, and some chicken. Foods to limit on this diet: butter, red meat, margarine, sweets and pastries, whole fat cheese, and fried or fast food. From Medical Xpress:

Eating away at cognitive decline: MIND diet may slow brain from aging by 7.5 years

While cognitive abilities naturally diminish as part of the normal aging process, it may be possible to take a bite out of this expected decline. Eating a group of specific foods known as the MIND diet may slow cognitive decline among aging adults, even when the person is not at risk of developing Alzheimer's disease, according to researchers at Rush University Medical Center. This finding is in addition to a previous study by the research team that found that the MIND diet may reduce a person's risk in developing Alzheimer's disease.

The recent study shows that older adults who followed the MIND diet more rigorously showed an equivalent of being 7.5 years younger cognitively than those who followed the diet least. The results of the study recently were published online in the journal Alzheimer's & Dementia: The Journal of the Alzheimer's Association.

The National Institute of Aging funded study evaluated cognitive change over a period of 4.7 years among 960 older adults who were free of dementia on enrollment. Averaging 81.4 years in age....residents of more than 40 retirement communities and senior public housing units in the Chicago area. .... Martha Clare Morris, ScD, a nutritional epidemiologist, and colleagues developed the diet, whose full name is the Mediterranean-DASH Diet Intervention for Neurodegenerative Delay. As the name suggests, the MIND diet is a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets. Both diets have been found to reduce the risk of cardiovascular conditions, like hypertension, heart attack and stroke.

"Everyone experiences decline with aging; and Alzheimer's disease is now the sixth leading cause of death in the U.S., which accounts for 60 to 80 percent of dementia cases. Therefore, prevention of cognitive decline, the defining feature of dementia, is now more important than ever," Morris says.

The MIND diet has 15 dietary components, including 10 "brain-healthy food groups" and five unhealthy groups - red meat, butter and stick margarine, cheese, pastries and sweets, and fried or fast food. To adhere to and benefit from the MIND diet, a person would need to eat at least three servings of whole grains, a green leafy vegetable and one other vegetable every day—along with a glass of wine—snack most days on nuts, have beans every other day or so, eat poultry and berries at least twice a week and fish at least once a week. In addition, the study found that to have a real shot at avoiding the devastating effects of cognitive decline, he or she must limit intake of the designated unhealthy foods, especially butter (less than 1 tablespoon a day), sweets and pastries, whole fat cheese, and fried or fast food (less than a serving a week for any of the three).

Berries are the only fruit specifically to be included in the MIND diet. "Blueberries are one of the more potent foods in terms of protecting the brain," Morris says, and strawberries also have performed well in past studies of the effect of food on cognitive function.

Published on

An observational study of older adults found that the Mediterranean diet may help preserve the connections between neurons in the brain, by preserving the microstructure in the white matter of the brain. This appeared to have a strong cognitive benefit - equal up to 10 years of delayed cognitive aging in those who adhered to the Mediterranean diet most closely. So if you haven't started already, try eating what the Mediterranean diet stresses: fruits, vegetables, whole grains, seeds, nuts, legumes, olive oil, some fish, and some wine. And cut back on highly processed foods, meat, and high fat foods. It's not one or two foods, but overall diet that is important. From Medscape:

Mediterranean Diet May Preserve Brain Structural Connectivity

The Mediterranean diet may help preserve structural connectivity in the brain in older adults, results of a French study hint. Greater adherence to the Mediterranean diet was associated with preserved microstructure in extensive areas of the white matter up to a decade later, the study team found. And this appeared to be related to strong cognitive benefit, equal to up to 10 years of delayed cognitive aging for those with the greatest adherence, they say....The study was published online July 16 in Alzheimer's & Dementia. The Mediterranean diet has been associated with a lower risk for Alzheimer's disease, but the underlying mechanisms have been unclear.

The new findings are based on 146 nondemented older adults in the Bordeaux Three-City study, a prospective cohort initiated in 1999-2000 to study vascular risk factors for dementia. Participants provided information on their diet in 2001-2002 (at a mean age of 73 years), underwent brain MRI an average of 9 years later (including diffusion tensor imaging)...On the basis of dietary assessment, 26% of participants had a low Mediterranean diet (MedDi) score of 0 to 3, indicating poor adherence to the diet; 47% had medium scores (4 or 5); and 27% had higher scores (6 to 8) representing the best adherence to the diet.

In adjusted analysis, there was no significant association between the MedDi score and grey matter or white matter volume. However, there was a strong association between the MedDi and diffusion tensor imaging patterns, suggesting that higher MeDi adherence was associated with a "general pattern of preserved WM [white matter] microstructure in multiple bundles," the researchers say. And preserved white matter microstructure with higher adherence to the MedDi "appeared to delay cognitive aging by up to 10 years."

"Our results suggest that the Mediterranean diet helps preserve the connections between neurons, which appear to be damaged with aging, vascular brain diseases and neurodegenerative diseases such as Alzheimer's dementia," Dr Samieri told Medscape Medical News. "In addition, the regions which appeared preserved with greater adherence to the Mediterranean diet were extended and were not specific to a particular disease, suggesting that the Mediterranean diet may have the potential to prevent not only stroke (as previously demonstrated with the PREDIMED [Prevención con Dieta Mediterránea] trial) but also multiple age-related brain pathologies," she added.

The added finding that none of the individual components of the Mediterranean diet was strongly associated with imaging results "supports our hypothesis that overall diet quality may be more important to preserve brain structure than any single food," they write.

Published on

For many years it was thought that yo-yo dieting resulted in higher cancer risk. So the findings of this study are a relief. Researchers looked at weight cycling (yo-yo dieting) and incidence for all cancer and 15 individual cancers among more than 132,000 participants during 17 years of study and found NO association with overall risk of cancer or any individual cancer. So feel free to diet and lose weight for the health benefits. From Science Daily:

Yo-yo dieting not associated with increased cancer risk

The first comprehensive study of its kind finds weight cycling, repeated cycles of intentional weight loss followed by regain, was not associated with overall risk of cancer in men or women. The study by American Cancer Society investigators is the largest to date to investigate weight cycling with cancer risk....Weight cycling was also not associated with any individual cancer investigated. The authors of the study say people trying to lose weight should be encouraged to do so even though they may regain it.

With almost half of American adults reporting they are trying to lose weight, and with most weight loss not maintained, weight cycling is very common. Previous studies in animals and humans had suggested that weight cycling may affect biological processes that could lead to cancer, such as increased T-cell accumulation, enhanced inflammatory responses in adipose tissue, and lowered natural killer cell cytotoxicity. However, many of these findings have not been replicated, and at least two previous studies showed no associations between weight cycling and cancer.

For the latest study, researchers led by Victoria Stevens, PhD, American Cancer Society Strategic Director, Laboratory Services, examined weight cycling and cancer among more than 132,000 men and women enrolled in the Cancer Prevention Study II Nutrition Cohort. Begun in 1992/1993, the Nutrition Cohort gathered detailed dietary information from men and women ages 50 to 74 participating in the Society's larger Cancer Prevention Study II, to explore nutrition's effect on and cancer incidence and mortality. Investigators looked at weight cycling and incidence for all cancer and 15 individual cancers. More than 25,000 participants developed cancer during 17 years of study.

Published on

One study points out the difficulty of weight loss in overweight adults, because so few actually are able to get down to a normal weight or even lose a mere 5% of body weight (for example. 10 pounds for a 200 pound person or 15 pounds for a 300 pound person). The annual chance of an obese person attaining normal body weight is only 1 in 210 for men and 1 in 124 for women,and the annual chance of obese patients achieving five per cent weight loss was 1 in 12 for men and 1 in 10 for women.  The second study highlights how well weight loss treats "fatty liver" (which is a problem in middle-aged overweight people). Fatty liver or nonalcoholic steatohepatitis (NASH), which affects 2 to 5 percent of Americans, can be severe and can lead to cirrhosis, in which the liver is permanently damaged and scarred and no longer able to work properly.

After reading scientific studies nonstop for the last few years, it seems that the best, easiest way to lose weight is to have lifestyle changes rather than focusing just on a "weight-loss diet": increase activity levels (yes, walking counts) and switch to a more plant based diet or Mediterranean diet (lots of fruits, vegetables, whole grains, legumes, seeds, nuts, olive oil, some fish each week) and decrease the amount of typical Western style diet (highly processed foods. lots of meat and coldcuts, lots of fat, fast foods, soda). Try to only eat within 12 hours each day (for example, 8am to 8pm) and don't eat the other 12 hours. And of course eat fewer calories (it should be easier  to do if you substitute fruits and vegetables for high calorie processed foods such as ice cream, french fries, and sweets). And yes, of course it's really hard to lose weight, but the health benefits of weight loss are enormous. From Medical Xpress:

Low chance of recovering normal body weight highlights need for obesity prevention

The chance of an obese person attaining normal body weight is 1 in 210 for men and 1 in 124 for women, increasing to 1 in 1,290 for men and 1 in 677 for women with severe obesity, according to a study of UK health records led by King's College London. The findings, published in the American Journal of Public Health, suggest that current weight management programmes focused on dieting and exercise are not effective in tackling obesity at population level.The research, funded by the National Institute for Health Research (NIHR), tracked the weight of 278,982 participants (129,194 men and 149,788) women using electronic health records from 2004 to 2014.

The annual chance of obese patients achieving five per cent weight loss was 1 in 12 for men and 1 in 10 for women. For those people who achieved five per cent weight loss, 53 per cent regained this weight within two years and 78 percent had regained the weight within five years.

Overall, only 1,283 men and 2,245 women with a BMI of 30-35 reached their normal body weight, equivalent to an annual probability of 1 in 210 for men and 1 in 124 for women; for those with a BMI above 40, the odds increased to 1 in 1,290 for men and 1 in 677 for women with severe obesity. Weight cycling, with both increases and decreases in body weight, was also observed in more than a third of patients. The study concludes that current obesity treatments are failing to achieve sustained weight loss for the majority of obese patients.

Dr Alison Fildes, first author from the Division of Health and Social Care Research at King's College London (and now based at UCL), said: 'Losing 5 to 10 per cent of your body weight has been shown to have meaningful health benefits and is often recommended as a weight loss target..... More importantly, priority needs to be placed on preventing weight gain in the first place.'

From Medical Xpress:  Weight loss for a healthy liver

Weight loss through both lifestyle modification and bariatric surgery can significantly reduce features of nonalcoholic steatohepatitis (NASH), a disease characterized by fat in the liver, according to two new studies published in Gastroenterology..."we most commonly see this condition in patients who are middle-aged and overweight or obese," said Giulio Marchesini, MD, from University of Bologna, Italy, and lead author of an editorial summarizing these two studies. "These two large prospective cohort studies strengthen the evidence that, no matter how you lose weight, weight loss improves liver health. Both bariatric surgery for morbidly obese patients or lifestyle modifications are viable options."

Lifestyle modifications: Eduardo Vilar-Gomez and colleagues from Cuba report in Gastroenterology that a weight reduction of 10 percent or more, induced by a comprehensive lifestyle program, is necessary to bring about NASH resolution and reverse scarring of the liver in overweight and obese patients. To a lesser degree, modest weight loss (7 to 10 percent) reduced disease severity in certain subsets of patients, including male patients and those without diabetes. Conversely, 93 percent of the patients with little or no weight reduction (less than 5 percent) experienced worsening of liver scarring....While promising, less than 50 percent of patients achieved the necessary weight loss goal of 7 to 10 percent, providing a stark reminder of the sustainability of weight loss interventions.

Bariatric surgery: For appropriate morbidly obese patients with NASH who have previously failed to lose weight through lifestyle modifications, bariatric surgery may be considered. In the second Gastroenterology study, Guillaume Lassailly and colleagues from France report that, one year after bariatric surgery, NASH had disappeared from 85 percent of patients and reduced the pathologic features of the disease after 1 year of follow-up. NASH disappeared from a higher proportion of patients with mild NASH before surgery (94 percent) than severe NASH (70 percent). More studies are needed to determine the long-term effects of bariatric surgeryin morbidly or severely obese patients with NASH.

Published on Leave a comment on What’s In the “Natural” Flavors In Our Foods?

I've been reading and thinking about "natural flavors" ever since my earlier posts about food additives (April 20, 2015, August 19, 2014). What exactly are natural flavors and how are they different from artificial flavors?  And why are they even found in organic foods? The more I read, the more I want to avoid them , but it seems to be really, really hard to do so because they seem to be everywhere, even in what we think of as basic foods (e.g., butter). Bottom line: both are chemicals concocted in labs and manufactured in factories. Read labels and try to eat as many unprocessed foods as possible to avoid them.We know very little about many of them, and if they have health effects. Note that the term "natural flavors" may include many chemicals in the "flavor mixtures" (incidental additives) that don't have to be listed on the labels. Currently there are more than 2700 natural flavors being used in the USA. The following are excerpts from articles and a book published in 2015.

From CNN:   What are natural flavors, really?

Look at the food label of almost any packaged good you consume and odds are you'll spot the term "natural flavors." But have you ever wondered what this mysterious additive actually contains? The answer isn't as clear as you might think.Though natural flavors may sound better than their presumably chemical-laden alternative — artificial flavors — it turns out they are not actually all that different.

In the Environmental Working Group's Food Scores database of over 80,000 foods, "natural flavor" is the fourth most common ingredient listed on labels. The only ingredients that outrank it: salt, water and sugar. Yet, natural flavoring isn't nearly as simple as these three pantry staples."Natural and artificial flavors play an interesting role in food. They're essentially providing the taste and often they're added to make the food more appealing, or to potentially replace something that's lost through processing, storage or in some cases even from pasteurizing," says David Andrews, senior scientist at the Environmental Working Group. One place you'll often spot natural or artificial flavor is in orange juice; manufacturers will add faux flavor to juice after it's packaged in the plant, to ensure uniformity.

"The differentiation is really down to the origin of those molecules, whether synthetically processed in a lab or purified in a lab but from a natural source," Andrews says. Here's where it gets even muddier: Added flavoring, both natural and artificial, could contain anywhere from 50 to 100 ingredients. And all of the extra ingredients in flavors often aren't as innocent as you'd hope they would be."The mixture will often have some solvent and preservatives — and that makes up 80 to 90 percent of the volume [of the flavoring]. In the end product, it's a small amount, but it still has artificial ingredients," Andrews says.  ...continue reading "What’s In the “Natural” Flavors In Our Foods?"

Published on Leave a comment on Why Breastfeeding Is So Important

There has been much discussion recently about breastfeeding - why is it so important? Is it really better than formula? The answer is: YES, breastfeeding is the BEST food for the baby, and for a number of reasons. Not only is it nature's perfect food for the baby, but it also helps the development of the baby's microbiome or microbiota (the community of microbes that live within and on humans).

Specifically, breast milk transmits about 700 species of bacteria to the baby - bacteria that are important in developing the baby's microbiota, bacteria that are important for the baby's development and health in many ways (including the immune system). No formula does that. Not even close.

There is obviously much we don't know or understand yet, but finding 700 species in breast milk is a big deal. The most variety was in colostrum (the first milk), but even after 6 months (mature milk) they found hundreds of species of bacteria. What was also interesting was that the bacteria species in the breast milk varied whether the baby was born by vaginal birth, unplanned cesarean, or planned cesarean (this last had a somewhat different bacterial community which persisted through the 6 months of the study).

By the way, in the original study, the authors made a point of saying that the 700 bacteria species are NOT bacterial contaminants, but meant to be there! (for those who want to sterilize and pasteurize everything because they think that all bacteria are bad).

This study is from 2013, but well worth reading. From Science Daily: Breast milk contains more than 700 species of bacteria, Spanish researchers find

Researchers have traced the bacterial microbiota map in breast milk and identified the species of microbes taken from breast milk by infants. The study has revealed a larger microbial diversity than originally thought: more than 700 species. The breast milk received from the mother is one of the factors determining how the bacterial flora will develop in the newborn baby.

A group of Spanish scientists have now used a technique based on massive DNA sequencing to identify the set of bacteria contained within breast milk called microbiome.  Colostrum is the first secretion of the mammary glands after giving birth. In some of the samples taken of this liquid, more than 700 species of these microorganisms were found, which is more than originally expected by experts.

"This is one of the first studies to document such diversity using the pyrosequencing technique (a large scale DNA sequencing determination technique) on colostrum samples on the one hand, and breast milk on the other, the latter being collected after one and six months of breastfeeding," explain the coauthors, María Carmen Collado, researcher at the Institute of Agrochemistry and Food Technology (IATA-CSIC) and Alex Mira, researcher at the Higher Public Health Research Centre (CSISP-GVA).

The most common bacterial genera in the colostrum samples were Weissella, Leuconostoc, Staphylococcus, Streptococcus and Lactococcus. In the fluid developed between the first and sixth month of breastfeeding, bacteria typical of the oral cavity were observed, such as Veillonella, Leptotrichia and Prevotella....The study also reveals that the milk of overweight mothers or those who put on more weight than recommended during pregnancy contains a lesser diversity of species.

The type of labour also affects the microbiome within the breast milk: that of mothers who underwent a planned caesarean is different and not as rich in microorganisms as that of mothers who had a vaginal birth. However, when the caesarean is unplanned (intrapartum), milk composition is very similar to that of mothers who have a vaginal birth.

These results suggest that the hormonal state of the mother at the time of labour also plays a role: "The lack of signals of physiological stress, as well as hormonal signals specific to labour, could influence the microbial composition and diversity of breast milk," state the authors.

And yes, what you eat while breastfeeding has an effect on the breast milk. From Science Daily:  Carotenoid levels in breast milk vary by country, diet

A Purdue University-led analysis of breast milk concludes that levels of health-promoting compounds known as carotenoids differ by country, with the U.S. lagging behind China and Mexico, a reflection of regional dietary habits. Carotenoids are plant pigments that potentially play functional roles in human development and are key sources of vitamin A, an essential component of eye health and the immune system.

The carotenoid content of a woman's breast milk is determined by her consumption of fruits and vegetables such as squash, citrus, sweet potatoes and dark, leafy greens.