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When we eat food, we eat all the microbes that live on and in the food. But how many microbes do we eat daily? An interesting study was published a few years ago that tried to answer this question. The researchers found that the average American adult ingests between 1 million to over 1 billion microbes every day!

The University of California researchers conducted the study in 2014 by analyzing meals representing three typical dietary patterns: 1) the average American diet (lots of convenience foods) (2) the USDA recommended diet (emphasis on fruits and vegetables, lean meat, dairy, and whole grains), and 3) vegan diet (excludes all animal and dairy products).

They found that Americans likely consume between one million to about 1.3 billion live microbes daily from foods and beverages.  The highest numbers (3-fold higher) were in the USDA recommended meal plan, because it involved 2 meals with fermented foods (that had not been heat-treated or pasteurized, which kill many bacteria). Fresh produce also has high numbers of bacteria (e.g., an apple has 100 million bacteria!).

Fermented foods (e.g. kimchi, sauerkraut, yogurt, kefir, traditional pickles, kombucha, natto, tempeh, miso) are loaded with microbial species. Recent research shows that eating a serving or 2 of fermented foods daily is a quick way to improve health (by lowering inflammation) and increasing the diversity of bacterial species in the gut microbiome.

Ingesting higher numbers of microbes from foods is desirable  - because having more species in the gut is considered a sign of health. Some of the microbes we ingest join our existing gut microbes, but others just pass through our gut and leave (the "transient microbiome"). Research finds that microbes can have beneficial effects even as they pass through.

Excerpts from the Lang, Eisen, Zivkovic study (2014) study, from Peer Journal: The microbes we eat: abundance and taxonomy of microbes consumed in a day's worth of meals for three diet types.

...Little is known about the effects of ingested microbial communities that are present in typical American diets, and even the basic questions of which microbes, how many of them, and how much they vary from diet to diet and meal to meal, have not been answered.   ...continue reading "We Eat Millions Of Microbes Each Day"

Over the course of the last two decades there have been changes in the American diet. A recent study found that Americans now eat more ultra-processed foods than ever (53.5% of calories), and have decreased their consumption of minimally processed foods (fruits, vegetables, whole grains, dairy, meat). This is not good for health.

Consumption of ultra-processed foods is linked to obesity and some chronic diseases. It is also not good for the gut microbiome (the community of millions of bacteria, fungi, and viruses that live in the intestines). Ultra-processed foods include sugary breakfast cereals, sweets, frozen pizza, soda, fast food, salty snacks, canned soup. They can contain preservatives, additives, artificial ingredients, and emulsifiers (which are linked to gut inflammation).

The study by New York University researchers found that ultra-processed food consumption grew from 53.5 percent of calories in the beginning of the period studied (2001-2002) to 57 percent at the end (2017-2018). They found that ready-to-eat or just heat meals (e.g., frozen dinners) increased the most, while the intake of some sugary foods and drinks (e.g. soda) declined.

Most of the decrease in minimally processed whole foods (from 32.7 percent to 27.4 percent of calories in two decades) was mostly due to people eating less meat and dairy. And who increased their intake of ultra-processed foods the most during this time? Older adults (age 60 and over), who also decreased their intake of whole foods the most over 2 decades.

Bottom line: try to increase your intake of real whole foods, and decrease your intake of ultra-processed foods. This would benefit your gut microbiome (feed the good gut microbes with whole foods: fruits, vegetables, whole grains, legumes, seeds, nuts) and your health.

From Science Daily - Americans are eating more ultra-processed foods

Consumption of ultra-processed foods has increased over the past two decades across nearly all segments of the U.S. population, according to a new study by researchers at NYU School of Global Public Health.  ...continue reading "Americans Are Eating More Ultra-Processed Food Than Ever"

Those who enjoy a little "potty humor" will like the results of a recent nutrition study comparing the results of a Western style diet (high fat, low fiber) to a high fiber Mediterranean diet. The high fiber diet resulted in much larger, softer stools, and an increase in stomach noises and farting. (Yes, they weighed their stools and counted daily farts!) There was no change in the number of stools per day.

In the study 18 healthy men followed both types of diets for two week periods (first one diet, then a break, and then the other diet). The high fiber diet (54.2 grams fiber per day) resulted in numerous beneficial changes, especially nurturing healthy gut bacteria and metabolic improvements. The low fiber Western diet only had an intake of 4.7 g fiber per day. Interestingly, all participants were told to avoid fermented dairy products (e.g. yogurts) during the study.

The high fiber diet resulted in greater numbers of beneficial bacteria in the gut without any major changes in the core microbiome (microbial community). There were also numerous gut microbial metabolic improvements while on this diet. Interestingly, men who already had a more diverse gut microbiota (which is a sign of health) and routinely already ate more fiber rich plants foods, had less farting and stomach noises during the study.

Think of it this way: your diet is what feeds and nurtures the microbes living in your gut. Some microbes are associated with chronic diseases, and some with health - so you want to nurture the health-associated bacteria by eating a diet rich in plant foods (Mediterranean style diet).

By the way, a recent study found that eating fermented foods is a quick way to increase gut microbial diversity and health. It's beneficial to add some fermented foods (e.g. yogurt, kimchi, sauerkraut, kefir) to your regular diet.

From New Scientist: Men fart more when eating a plant-based diet due to good gut bacteria

Plant-based diets cause men to fart more and have larger stools, researchers have found – but that seems to be a good thing, because it means these foods are promoting healthy gut bacteria.  ...continue reading "Farts and Good Gut Health"

Over the years many studies have found that eating nuts is good for health and good for the gut microbiome. Now, a study that looked at the effect of adding pecans to the daily diet can be added to the list.

The Univ. of Georgia researchers found that adding about 1/4 cup (68 grams) pecans to the daily diet for 8 weeks improved cholesterol levels. A conclusion is that pecans can be viewed as good for the heart or "cardioprotective".

In the study they randomly assigned 52 adults who were at risk for heart disease (they were overweight or had hypercholesterolemia) to 1 of 3 groups, including a control group with no pecan intake. As one of the researchers (Dr. Cooper) said: "We had some people who actually went from having high cholesterol at the start of the study to no longer being in that category after the intervention.

After 8 weeks of eating 1/4 cup pecans daily, there were lower levels of fasting total cholesterol, LDL cholesterol, triglycerides, TC/HDL cholesterol ratio, non-HDL cholesterol, and apolipoprotein B in the blood There were no changes in the control (no pecan) group.

By the way, do you remember years ago when doctors cautioned people about eating nuts?  That they were very high calorie and should be avoided? Hah! ... The view nowadays: Pecans are high in healthy fatty acids and fiber, both of which are linked to lower cholesterol. Eating nuts frequently also reduces the risk of several chronic diseases, including heart disease, type 2 diabetes, some cancers, and are beneficial for cognitive health.

From Science Daily: Pecan-enriched diet shown to reduce cholesterol

While the proper pronunciation of pecan remains a subject of debate, University of Georgia researchers have shown the tree nut can dramatically improve a person's cholesterol levels.  ...continue reading "Pecans Are A Healthy Addition to the Diet"

Recently there have been studies with conflicting results about the health benefits or harms from coffee consumption. Overall, it seems like moderate intake is OK and beneficial for adults, but too much may cause harm. And avoid caffeinated coffee if pregnant. Yesterday I posted about several recent studies finding health benefits from daily coffee consumption.

Coffee has anti-inflammatory effects, and contains more than a thousand chemical compounds. Over the years many studies found health benefits with regular and decaffeinated coffee, especially when a filter is used in the brewing process (e.g. drip coffee). But when the coffee is made by methods that don't filter the coffee (e.g. French press) the results may show harm, especially if large quantities are consumed daily.

The following are two recent studies finding that coffee consumption is associated with health benefits, and two studies finding potential harm from coffee consumption of over 6 cups a day. Note that whether the coffee is filtered or not may make a difference in results (the last 2 studies).

From (Jan. 11, 2021) Science Daily: Higher coffee intake may be linked to lower prostate cancer risk ...continue reading "Coffee Can Have Health Benefits, But Perhaps Harmful In Large Amounts"

It has been known for a while that eating fermented foods and high fiber foods is healthy for us. A recent study confirms this view. Researchers at the Stanford Univ. of Medicine found that eating fermented foods actually reduces inflammation and increases the diversity of gut microbes (gut microbiome).

Researchers randomly assigned volunteers to one of 2 groups for 10 weeks: the fermentation foods group, and the high fiber group. Surprisingly, the group eating the high fiber diet for 10 weeks did not have changes in microbial diversity or changes in the 19 inflammatory markers studied. Instead, the researchers reported that the high-fiber diet "changes microbiome function and elicits personalized immune responses".

The fermented foods group ate a diet rich in yogurt, kefir, fermented cottage cheese, kimchi and other fermented vegetables (e.g. sauerkraut, traditional dill pickles), vegetable brine drinks, and kombucha tea. Each day they ate 6 servings (1/2 cup = 1 serving generally). The high fiber diet was rich in legumes, seeds, whole grains, nuts, vegetables, and fruits (increased their fiber intake from about 22 grams per day to 45 grams).

The fermented foods group ate six servings daily (e.g. 1/2 cup yogurt, kefir, fermented cottage cheese, kimchi, sauerkraut, traditional dill pickles, and kombucha tea). The high fiber group increased their fiber intake from about 22 grams per day to 45 grams, by eating a diet rich in legumes, seeds, whole grains, nuts, vegetables, and fruits.

High-fiber diets are associated with numerous health benefits such as lower rates of numerous chronic diseases and mortality. The consumption of fermented foods can help with weight maintenance and may decrease the risk of diabetes, cancer, and cardiovascular disease.

From Futurity: Fermented Food Diet Boosts Microbiome and Cuts Inflammation

In a clinical trial, 36 healthy adults were randomly assigned to a 10-week diet that included either fermented or high-fiber foods. The two diets resulted in different effects on the gut microbiome and the immune system. 
...continue reading "Fermented Foods Are Good For Your Gut Microbiome"

The results of a large study adds more evidence to what we have long suspected: eating a Southern-style diet (fried foods and sugary drinks!) increases the risk for sudden cardiac death (up to 46% higher risk), while eating a plant-based or Mediterranean style diet appears to lower that risk.

Sudden cardiac death (SCD) occurs when the heart suddenly stops beating, and death occurs within one hour from the onset of symptoms. Heart disease (coronary artery disease) is the most common underlying cause of SCD (75 to 80% of cases), but it can also have other causes (e.g. heart failure, valve disease). Sudden cardiac death is quite common in the US - about 1 in every 7.5 deaths (or nearly 367,000 deaths in 2016).

Univ. of Alabama researchers looked at 5 dietary patterns that people ate over a 10 year period:  plant-based (Mediterranean), Southern, convenience food, alcohol & salad, and sweets. People generally eat foods from all 5 groups, but what is significant is the primary pattern - what the person mostly eats. The Southern diet is most prevalent in the southeastern US, which is also known as the "Stroke Belt", due to the higher stroke death rate there.

A Southern-style dietary pattern is characterized by fried foods, added fats,  eggs, organ meats (such as liver or giblets), processed meats (e.g. bacon, hotdogs, cold cuts), and sugar-sweetened beverages. A plant-based or Mediterranean dietary pattern is rich in fruits, vegetables, seeds, nuts, whole grains, legumes (beans), and fish, and low in processed meats, added fats, and fried foods.

The bottom line here is that what you eat has an effect on your health, including heart health. Best is a diet rich in plant-based foods - which also happens to be fiber rich and best for feeding beneficial microbes in the gut. Try to eat at least a minimum of 5 to 6 servings of fruits and vegetables each day, but more (up to 8 or 9 servings) might be even better.

From Science Daily: The Southern diet - fried foods and sugary drinks - may raise risk of sudden cardiac death

Regularly eating a Southern-style diet may increase the risk of sudden cardiac death, while routinely consuming a Mediterranean diet may reduce that risk, according to new research published today in the Journal of the American Heart Association, an open access journal of the American Heart Association.  ...continue reading "A Southern Style Diet Linked to Increased Risk of Sudden Cardiac Death"

Some good news. A recent study found that eating just 2 servings (a cup) of fruit per day is associated with a 36% lower risk for type 2 diabetes after 5 years (as compared to those who eat less than 1/2 a serving) . Doesn't sound like so much fruit, but appears to have a big effect.

However, in this Australian study, the association did not hold for fruit juice. Only for eating whole fruits.

From Science Daily: People who eat a healthy diet including whole fruits may be less likely to develop diabetes

A new study finds people who consume two servings of fruit per day have 36 percent lower odds of developing type 2 diabetes than those who consume less than half a serving. The research was published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.  ...continue reading "Eating Fruit Linked To Lower Risk of Type 2 Diabetes"

It has long been known that eating oily fish (e.g. salmon, sardines) has health benefits for the heart. But it also looks like regularly eating sardines may be a good way to lower the risk of getting type 2 diabetes, as well as improving heart health.

In a study (conducted in Spain) 152 persons at risk for developing type 2 diabetes ("pre-diabetes") were randomly assigned to one of 2 groups for 1 year: Group 1 regularly ate sardines +  followed a diabetes preventive diet, or Group 2 ate the same diabetes preventive diet, but without sardines. All participants were 65 years or older.

They found that after 1 year, the sardine group had greater health improvements than the non-sardine group. Fewer in the sardine group were still in the prediabetes group, and fewer had developed type 2 diabetes. The sardine group also had decreased triglycerides (good), greater increases in healthy HDL cholesterol, reduced insulin resistance, and lower blood pressure, as compared to the non-sardine group.

The sardine group also had higher taurine levels in the blood, as well as increases in nutrients linked to health benefits, including omega-3 EPA and DHA, vitamin D, and fluorine. Taurine has antioxidant and anti-inflammatory benefits.

What was their weekly consumption of sardines? They consumed 200 g of canned sardines in olive oil per week - eaten as 100 g servings twice per week. Which is a little less than eating two of the little 125 g cans of sardines in olive oil available at the grocery store. It was recommended that they eat the entire sardine, including bones, due to their rich content of calcium and vitamin D. [By the way, while the researchers don't discuss this - increased extra virgin olive oil consumption also has health benefits.]

Medscape article: Sardines Linked to Reduced Type 2 Diabetes Risk

Excerpts from Medical Xpress: Eating sardines regularly helps prevent type 2 diabetes

The health benefits of sardines and oily fish are widely known: their high levels of unsaturated fats help to regulate cholesterol levels and prevent the onset of cardiovascular diseases. However, the benefits don't end there.  ...continue reading "Eating Sardines Linked to Lower Diabetes Risk"

Iodine is an essential mineral for health, especially during pregnancy, because it is needed for intellectual development and thyroid functioning. For years people bought iodized table salt at the grocery store in order to make sure that they have enough iodine in the diet. However, the use of other salts (e.g. Himalayan salt) that don't have added iodine, and following a vegan or vegetarian diet can increase the risk of iodine deficiency.

A small study by Australian researchers looked at iodine levels in 2 groups of pregnant women, who were either vegan/plant-based diet participants or omnivores (eating both meat and plants). Both groups had urine with iodine levels below the World Health Organization recommended 100 µg per liter, but the vegan/plant-based group was far lower at 44 µg per liter. Those eating Himalayan salt had severely deficient levels: 23 µg per liter. The study did not look at the intellectual functioning of the infants after they were born.

How to get enough iodine in the diet? Foods containing iodine are seafood, seaweed, bread fortified with iodine, iodized salt, eggs, and dairy foods. Also, iodine supplements. Research indicates that adequate iodine intake before conception is necessary to ensure optimal maternal thyroid function during pregnancy, which is required for fetal intellectual development.

Medical Xpress: Poor iodine levels in pregnancy poses risks to fetal intellectual development

A growing number of young Australian women are at increased risk of having children born with impaired neurological conditions, due to poor iodine intake.  ...continue reading "Low Iodine Levels During Pregnancy Poses Risk to the Baby"