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Once again a study found that a diet rich in fruits, vegetables, whole grains, seeds, legumes, nuts, fish, and extra virgin olive oil is beneficial to the huge numbers of microbes living in our gut (the gut microbiome). This type of fiber-rich dietary pattern is generally called the Mediterranean diet.

The Mediterranean diet is associated with health in a number of ways: lower frailty in elderly persons, lowered risk of death and a number of diseases, as well as lowered levels of inflammation. Chronic inflammation is linked to cancers and a number of diseases - thus the goal is to keep inflammation levels down.

Researchers found that elderly persons eating a Mediterranean style diet for one year had beneficial effects on their gut microbes (after all, they were feeding the good gut microbes), which in turn resulted in less frailty, better cognitive function (including memory), and lower levels of chronic inflammation. There was an increase in beneficial microbes that are associated with health and lower levels of inflammation.

On the other hand, the group of persons eating their usual Western style diet (low in fiber, high in fats , meats, sugar, highly processed foods) did not show beneficial changes in their gut microbiome. They showed negative changes (deterioration) in the type of gut microbes,  and also higher levels of chronic inflammation. After all, they were feeding the microbes associated with poor health and inflammation.

What was interesting was that they looked at the gut microbial communities of 612 persons (aged 65-79 years) who lived in five different countries (Poland, Netherlands, UK, France and Italy) - both at the start (baseline) and after a year. At baseline they could see that country-specific patterns in dietary habits were also reflected in the microbiome profiles.

And after a year there were similar positive changes in the gut microbes in all of those eating a Mediterranean style diet, especially with an increase in "keystone species" - those that are especially important for gut health, but also linked to better health and better cognitive (mental) functioning.

Some of the beneficial bacteria that increased in the Mediterranean diet group: Faecalibacterium prausnitzii, along with Roseburia (R. hominis), Eubacterium (E. rectaleE. eligensE. xylanophilum), Bacteroides thetaiotaomicronPrevotella copri and Anaerostipes hadrus. A majority of these species are associated with health benefits [e.g. production of short chain fatty acids (SCFAs) and lower risk of frailty] and with anti-inflammatory properties. They also are associated with a lower risk for diseases such as type 2 diabetes and colorectal cancer. 

In contrast, the control group that ate a normal Western diet (fats, processed foods, low in fiber, high in meat and sugar) had an increase in  Ruminococcus torquesCollinsella aerofaciensCoprococcus comesDorea formicigeneransClostridium ramosumVeillonella disparFlavonifractor plautii and Actinomyces lingnae. An increase in the abundances of R. torquesC. aerofaciensC. ramosum and V. dispar have been associated with type 2 diabetes and colorectal cancer, atherosclerosis, cirrhosis, and inflammatory bowel disease.

A key finding was that the findings suggest that eating a Mediterranean style diet "modulates the microbiome in a direction positively associated with health". In other words, the benefit of the diet was that it fed beneficial gut microbes that improved health.

Note that these beneficial microbes are NOT found in any supplements or probiotics. You must eat the fiber-rich whole foods!

From Medical Xpress: Mediterranean diet promotes gut bacteria linked to 'healthy ageing' in older people  ...continue reading "Feed Your Gut Microbes With A Mediterranean Diet"

Once again a study finds an association between a Western diet (lots of processed meat, red meat, fried food, desserts, low fiber, high in refined grains, sugar sweetened beverages, and high-fat dairy) and a poor health outcome - this time a significantly higher incidence of late-stage age-related macular degeneration (AMD).

Interestingly though, a Western dietary pattern did not seem to be associated with whether a person developed early AMD - only with whether it would progress to late-stage AMD. And late-stage AMD is the one that results in loss of central vision (in the retina), which means a person will then be unable to drive.

This study followed 1278 people over an 18 year period. Those who ate a Western style diet (considered unhealthy) had a 3 times higher rate of late-stage AMD as compared to those who had a "prudent" (healthy) dietary pattern. Out of 1278 persons - 117 developed early AMD and 27 developed late AMD (20 of them progressed from no AMD to late AMD over the 18 years, and 7 progressed from early AMD to late AMD).

What kinds of foods seemed especially protective? The researchers said that eating the following  foods appeared protective: cruciferous (e.g. broccoli), foods high in carotene (e.g. carrots), dark green leafy and other vegetables, poultry, fresh fruits, legumes, fish and sea foods - what they called part of a "prudent" diet, but can also be thought of as a Mediterranean dietary pattern.

One thing I question is whether "high fat dairy" (which they said was margarine & butter) should have lumped together margarine and butter. After all, margarine is a concoction made with trans fats and linked to health problems, while butter (made from milk/cream) is very different.

From Science Daily: Poor diet linked to age-related macular degeneration  ...continue reading "A Person’s Diet And Age-Related Macular Degeneration"

New research is published every day, but only some studies are big research stories or game-changers. The following are what I consider some of the most memorable studies of 2018 – some in a good way, but some of the others have left me with a sense of horror. I think there will be follow-up research, so keep an eye out for more on these important topics.

Are we heading toward a time in the not so distant future when all men are infertile? (Due to exposure to all the endocrine disruptors around us.) Will All Men Eventually Be Infertile? This was posted September 5, 2018.

Researchers are now seriously investigating and finding evidence that microbes may be causing Alzheimer’s disease. This approach is rapidly finding support in the medical field, and may lead to possible ways to treat or prevent the disease. Possible Herpes Virus Link to Alzheimer’s Disease was posted July 13, 2018, and Herpes Viruses and Alzheimer's Disease on  June 22, 2018.

Type 2 Diabetes May Be Reversed With Weight Loss was posted August 10, 2018. This study and an earlier similar study from 2016 found that losing over 30 pounds over a short period can reverse type 2 diabetes - 46% in the 2018 study and 60% (in people who had it less than 10 years) in the earlier study.

More and more evidence is accumulating that certain diets are anti-inflammatory. Especially beneficial are diets rich in fruits, vegetables, seeds, nuts, legumes (beans), and whole grains - which also have a lot of fiber. This is exciting research because chronic low-grade inflammation is linked to a number of chronic diseases (heart disease, cancer, etc.). Fruits, Vegetables, and Whole Grains Lower Inflammation – posted August 1, 2018.

[Related to this last topic is one of the most eye-opening studies I have ever read on how what one eats has a quick effect on gut microbes and health of the gut (including inflammation of the colon): Changing Diet Has Big Effect On Colon Cancer Risk – posted April 28, 2015.]

Is the Mediterranean style diet the future in breast cancer prevention? The following study was done in primates, but it makes sense that the results would also be true for humans: that the type of diet eaten influences the breast microbiome. This means the community of microbes that live in the breast. Yes, it's true - studies show that there is a breast microbiome and it varies between those who have breast cancer and those who don't (healthy breasts).

The study looked at macaque monkeys who were fed either a Mediterranean style diet or a Western style diet for 31 months, and then their breast tissue was examined. They found microbial differences in the breast tissue among the 2 groups, including  greater numbers (abundance) of Lactobacillus species in the primates that had been eating the Mediterranean diet.

Lactobacillus species are generally considered beneficial to humans (which is why they are added to many foods and supplements) and studies suggest they may have anti-tumor effects. Some research has found microbial differences between healthy and malignant (cancerous) human  breast tissue  - including lower Lactobacillus numbers or "abundance" in the malignant breast tissue (compared to those with benign breast lesions). Researchers say it suggests that microbial imbalances (dysbiosis) of breast tissue could be a possible driver of breast cancer .

Studies already show that a person's diet influences the gut microbiome. This study shows diet directly influences microbial communities far away from the gut - in the breasts. Unfortunately it is not stated in the study what Lactobacillus species increased in the breast tissue of primates fed a Mediterranean diet. There are many Lactobacillus species, and they are not equal in their effects (as our experiences with Lactobacillus sakei and sinusitis has shown).

Of course more studies are needed, but in the meantime - eat a diet rich in fruits, vegetables, whole grains, legumes (beans), nuts, and seeds. There are many other documented health benefits from a diet rich in those foods (frequently referred to as a Mediterranean diet). The diet is low in processed foods and high in fiber, and rich in "real foods". From Science Daily:

Diet affects the breast microbiome in mammals

Diet influences the composition of microbial populations in the mammary glands of nonhuman primates, researchers report October 2 in the journal Cell Reports. Specifically, a Mediterranean diet increased the abundance of probiotic bacteria previously shown to inhibit tumor growth in animals ...continue reading "Diet And The Breast Microbiome"

Two recent studies caught my eye – both reviews of scientific research that looked at the issue of diet and whether it contributes to the development of Intestinal Bowel Disease (IBD), specifically Crohn’s disease and ulcerative colitis. These are chronic inflammatory disorders of the gastrointestinal tract, and which are rapidly increasing in developed countries (over 1 million individuals in the US). The main question is: Does a person’s diet contribute to the development of IBD?

Both articles (one in the journal Nature Reviews and one in Immunology) said: YES, there is growing evidence that a person’s diet has a role in the development of IBD. Both articles stated that the current view is that some individuals may be genetically susceptible, and their diet (which feeds the microbes in the gut) then makes them more prone to the disease due to the mucosal lining becoming permeable and inflamed. Studies have shown that people with IBD have gut microbial communities that are imbalanced or out of whack (dysbiosis).

What does this mean? A person’s diet has a key role in what microbes live in the gut (human gut microbiome) – what one eats feeds the microbes in the gut, and a person’s general dietary pattern feeds some types of microbes and not others. So what one eats determines what lives in the gut microbial community. Unfortunately a fiber-deficient diet (typical Western diet) is both linked to increased mucosal inflammation (the mucus layer of the intestines) and it makes it leaky. In other words, a fiber deficient diet impairs the mucus layer of the intestines. Animal studies also support this (that the diet regulates mucosal barrier function).

People in developed countries such as the US typically eat a Western style diet. A Western diet is characterized by high amounts of red meat, processed food, high-fat foods, refined grains, sugary desserts, and low intakes of dietary fiber. However, the Western style diet has been linked to increased mucosal inflammation of the intestines, and to a higher incidence of a number of diseases, including ulcerative colitis and Crohn’s disease.

What diet is best? A diet rich in fruits and vegetables, whole grains, nuts, seeds, legumes (beans), and fish. Low in red meat, but moderate amounts of poultry. High in vitamin D, and high in omega-3 fatty acids. High in dietary potassium and zinc. Eat the foods, not supplements. One good example to follow is the Mediterranean diet. Think of it this way: high fiber diets lower inflammation in the gut, low fiber diets increase inflammation.

Both articles had similar diagrams showing that diet has an effect on the microbes in the gut (the microbiome), which results in either 1) a healthy mucosal lining of the intestines, or 2) a disturbed mucosal lining, disturbed permeability, and inflammation. The one article calls it the “mucinous layer” and the other calls it the gut “barrier” in the diagrams, but both are talking about the mucosal lining of the intestines.

The following image contrasts the effects on the intestines of the two types of diet - the intestines on the left have "homeostasis" (balance) from a healthy dietary pattern (lots of fiber, fruits& vegetables, etc) , and the one on the right has inflammation from a Western dietary pattern.  To see it more clearly, go to the original Figure 1. in the article by L. Celiberto et al: Inflammatory bowel disease and immunonutrition: novel therapeutic approaches through modulation of diet and the gut microbiome

The other review:  The role of diet in the aetiopathogenesis of inflammatory bowel disease

It will be great if more studies support a recent study finding that eating a Mediterranean style diet is associated with fewer psoriasis symptoms. The large study, which was conducted in France, found an inverse association with the Mediterranean diet - the more closely a person ate a Mediterranean diet, the less severe their psoriasis symptoms and the lower their serum C-reactive protein levels (which measures chronic systemic inflammation). Key things to remember are that psoriasis is an inflammatory condition and the Mediterranean diet is anti-inflammatory, and the typical Western diet is inflammatory (low in fiber, lots of highly processed foods, few fruits and vegetables, high in sugar, and red meat) .

The Mediterranean diet is rich in fruits and vegetables, whole grains, nuts, seeds, extra virgin olive oil, legumes (beans), fish, and light on red meat. Research finds that micronutrients, fiber, antioxidants, and polyphenols that are present in the Mediterranean diet reduce chronic systemic inflammation.  The Mediterranean diet has other health benefits - for example, it's good for the heart, is good for gut microbes, and linked to lower rates of several cancers. From Medical Xpress:

Could psoriasis patients eat their way to fewer symptoms?

A study of more than 3,500 French psoriasis patients found that the healthier their diet, the less severe their symptomsSpecifically, the closer an individual adhered to the nutritious "Mediterranean" diet, the less onerous their psoriasis became. This was true regardless of whether or not the patient was obese, the French researchers noted. 

...continue reading "Could the Mediterranean Diet Help With Psoriasis Symptoms?"

Once again, a study linked a person's diet with the chances of getting age-related macular degeneration (AMD). Macular degeneration is a leading cause of vision loss in Americans 60 years and older, and it has no cure. The study (conducted at the University of Bordeaux, France) found that people who eat a Mediterranean diet are less likely to develop advanced age-related macular degeneration. The study was presented at a conference (not a medical journal), but it builds on other research with similar findings.

What is the Mediterranean diet? It is a diet rich in fruits, vegetables, whole grains, legumes (beans), nuts, seeds, olive oil, and fish. The diet is a good source of fiber, omega-3 polyunsaturated fatty acids (especially fatty fish such as salmon, mackerel, and sardines), and of vitamin C, vitamin E, lutein, zeaxanthin, zinc, and copper. Lutein and zeaxanthin are carotenoids found in green, yellow and red vegetables. From Medscape:

Mediterranean Diet Linked With Lower Incidence of Advanced AMD

People who eat a Mediterranean diet are less likely to develop advanced age-related macular degeneration (AMD). That's according to research presented May 1 at ARVO 2018, the annual meeting of the Association for Research in Vision and Ophthalmology, in Honolulu, Hawaii.  "Higher adherence to the Mediterranean diet was associated with a 39% reduced risk of developing advanced AMD. These results highlight that eating a healthy diet, such as a Mediterranean-type diet, may help to limit progression to advanced AMD," Dr. Benedicte M. J. Merle of the University of Bordeaux, France, and her colleagues write in their abstract.  ...continue reading "Mediterranean Diet Linked to Lower Risk of Macular Degeneration"

Prostate cancer is something that men worry about, especially because it is the most common cancer in men, and because it can take several forms. On one hand, a tumor can be "indolent" or so slow growing that it just needs to be monitored, or sometimes it can be very aggressive and even lead to death. That's why the possibility of a dietary pattern (what a person eats) having an effect on the cancer's progression or aggressiveness is very exciting - if true, it would be something people could do to improve their prostate cancer outcome. Or perhaps even prevent it in the first place. Studies up to this point have been mixed, with no clear results.

A recent large study conducted in Spain found that those men with prostate cancer who had a high adherence to a Mediterranean diet had a lower risk of aggressive prostate cancer, as compared to those following a typical Western diet (large amounts of fatty dairy products, refined grains, processed meat, caloric beverages, sweets, fast food, and sauces) or a Prudent diet (low-fat dairy products, whole grains, fruits, vegetables, and juices). A Mediterranean dietary pattern is rich in fruits and vegetables, and also fish, legumes, boiled potatoes, olives and olive oil, vegetable oils, and a low intake of juices.

The researchers also discussed that there are many similarities with breast cancer and prostate cancer, including risk factors. They found in an earlier study in Spain that eating a Western diet is associated with breast cancer risk, the Prudent diet is not associated with breast cancer, and the Mediterranean diet seems to be protective for breast cancer. From Medical Xpress:

A more complete Mediterranean diet may protect against aggressive prostate cancer

In a new study published in The Journal of Urology, researchers determined that men who followed a Mediterranean diet, rich in fish, boiled potatoes, whole fruits, vegetables, legumes, and olive oil, and low consumption of juices had lower risk of aggressive prostate cancer (PC) than those who followed other dietary patterns like Prudent or Western diets. ..."Our results show that a diet oriented towards the prevention of aggressive tumors in the prostate should probably include important elements of the Mediterranean diet such as fish, legumes, and olive oil, and suggest that a high intake of fruits, vegetables, and whole grains might not be enough."

The authors explored the relationship between the risk of having PC and dietary patterns as part of the MCC-Spain study, a Spanish case-control study that involved 733 patients with histologically confirmed PC and 1,229 healthy men with a mean age of 66 years from seven Spanish regions. Anthropometric, epidemiologic, and dietary data were collected.

Adherence to the three dietary patterns of Western, Prudent, and Mediterranean, which characterize the dietary habits of the Spanish population, was evaluated, The Western [dietary] pattern includes consumption of large amounts of fatty dairy products, refined grains, processed meat, caloric beverages, sweets, fast food, and sauces. The Prudent pattern involves consumption of low-fat dairy products, whole grains, fruits, vegetables, and juices. Finally, the Mediterranean pattern consists of high consumption of fish, boiled potatoes, fruits, vegetables, legumes, and olive oil, and low consumption of juices. The diets were graded according to the degree of adherence to each pattern and assigned to four quartiles from lower to higher adherence within each pattern.

Only a high adherence to Mediterranean dietary pattern appeared to be associated with a lower risk of aggressive PC. Prudent and Mediterranean dietary patterns showed different effects in low and high grade tumors. 

PC was assessed using Gleason scores of tumor aggressiveness (<6 or ?6) and clinical stage (cT1b to cT4). A Gleason score of <6 typically indicates a less aggressive tumor with generally good prognosis. Lower clinical stage (cT1-cT2a) indicates a tumor that has not spread. Results indicated that for more aggressive and more extensive tumors (Gleason >6 and stages cT2b to cT4), only high adherence to the Mediterranean diet showed a statistically significant protective effect. All other dietary patterns and tumor characteristics showed little or no correlation and did not achieve statistical significance. [Original study.]

Once again the Mediterranean diet is linked to health benefits - this time a 40% lower incidence of certain types of breast cancer in postmenopausal women. Following a Mediterranean style diet has been linked in earlier studies to various health benefits, such as lower rates of heart disease, lower rates of early death, and certain cancers.

A strength of this study is that so many (62,573) Dutch postmenopausal women were followed for a long time (about 20 years). Their diet was analyzed, especially how closely it matched the Mediterranean diet or not. Since alcohol is a risk factor for breast cancer, and dose-related - it was not included as part of the Mediterranean diet in this study. The study found that following a Mediterranean diet with higher consumption of nuts, fruits, vegetables, and whole grains, appeared to be protective against certain breast cancers - it was associated with a reduced risk of estrogen receptor–negative (ER-) breast cancers. Unfortunately the researchers did not look at olive oil use in this study, because when it started in 1986, it was not typically used in the Netherlands. However, another good study found extra virgin olive oil to be a protective part (against breast cancer) of the Mediterranean diet. From Medscape:

Mediterranean Diet Cuts Some Breast Cancer Risk by 40%

Closely following a Mediterranean diet in everyday life may significantly reduce the risk for types of breast cancer that are associated with poorer prognoses in postmenopausal women, new research indicates. The traditional Mediterranean diet is characterized by a high intake of plant proteins, whole grains, fish, and monounsaturated fat, as well as moderate alcohol intake and low intake of refined grains, red meat, and sweets, say the study authors, led by Piet A. van den Brandt, PhD, an epidemiologist at the Maastricht University Medical Center in the Netherlands.

The new findings come from 62,573 Dutch women aged 55 to 69 years who provided information on dietary and lifestyle habits in 1986 and have since been followed for more than 20 years....The investigators found that women who most closely adhered to a Mediterranean diet had a 40% reduced risk for estrogen receptor–negative (ER-) breast cancer compared to women who adhered to the diet the least. They found a 39% reduced risk for progesterone receptor–negative (PR-)/ER- disease when comparing these same high- and low-adherence groups. Notably, in these results, the definition of the diet excluded alcohol intake, because the consumption of alcohol is a known risk factor for breast cancer....The authors also report that there were no significant associations with the diet and the risk of ER+ disease or total breast cancer.

Dr van den Brandt also explained that older women, who were the subjects of the new study, are more likely to derive benefit than younger women. "Generally speaking, postmenopausal breast cancer seems somewhat more influenced by environmental factors, such as lifestyle and diet, than premenopausal breast cancer, where genetic factors seem to play a more prominent role," he told Medscape Medical News.

Dr Toledo was the senior author of the only large, randomized trial to date in which postmenopausal women were assigned to a dietary intervention to promote their adherence to the traditional Mediterranean diet (JAMA Intern Med. 2015;175:1752–60). The study found that women with a higher adherence to the diet (supplemented with extra-virgin olive oil) showed a substantial reduction of their risk for breast cancer compared to a control group, as reported by Medscape Medical News.

One of the dreaded afflictions of getting older is age-related macular degeneration (AMD), which is a leading cause of vision loss in Americans 60 years and older. It has no cure. Thus this study finding that eating a Mediterranean diet, and especially lots of fruit, was associated with a lower risk of macular degeneration was welcome news. They also found a protective effect from drinking caffeinated beverages - about 78 mg of caffeine per day (about one cup of coffee or one shot of espresso). A Mediterranean diet stresses eating fruits, vegetables, nuts, whole grains, legumes, fish, seeds, and olive oil. From Science Daily:

Fruit-rich Mediterranean diet with antioxidants may cut age-related macular degeneration risk by more than a third

People who closely follow the Mediterranean diet -- especially by eating fruit -- may be more than a third less likely to develop age-related macular degeneration, a leading cause of blindness, according to a study presented at AAO 2016, the 120th annual meeting of the American Academy of Ophthalmology. The study is the first to identify that caffeine may be especially protective against AMD.

Many studies have confirmed the health benefits of the Mediterranean diet, which emphasizes eating fruits, vegetables, whole grains, legumes, nuts, healthy fats and fish, and limiting red meat and butter. The diet has been shown to improve heart health and reduced risk of cancer, but there has been little research on whether its benefits can extend to eye disease. To determine this, researchers studied a Portuguese population to see whether adherence to the diet impacted people's risk of AMD. Their findings revealed a significant reduction in risk in those who ate a Mediterranean diet most frequently, and particularly among those who consumed more fruit and caffeine.

Researchers at the University of Coimbra in Portugal studied 883 people age 55 or older in the central region of the country between 2013 and 2015. Of those, 449 had AMD in its early stages before vision loss, and 434 did not have AMD. Researchers assessed their diets based on a questionnaire asking how often they ate foods associated with the Mediterranean diet. The more they ate foods associated with the diet, the higher the score, from 0-9. Those who closely followed the diet scored a 6 or greater. Their findings were as follows:

Higher diet adherence scores meant lower AMD risk Of those who did not closely follow the diet (scored below a 6), 50 percent had AMD. Of those who did closely follow the diet (scored 6 or above), only 39 percent had AMD. This represents a 35 percent lower risk compared to those who did not adhere to the diet.

Fruits were especially beneficial Researchers analyzed consumption of foods and found that people who consumed higher levels of fruit were significantly less likely to have AMD. Of those who consumed 150 grams (about five ounces) or more of fruit a day: 54.5 percent did not have AMD and 45.5 percent had AMD. Overall, people who ate that much fruit or more each day were almost 15 percent less likely to have AMD, based on an odds ratio calculation.

Caffeine and antioxidants also were protective Researchers used a computer program to analyze the participants' consumption of micronutrients, according to their answers on the questionnaire. They found higher consumption of antioxidants such as caffeine, beta-carotene and vitamins C and E was protective against AMD. Of those who consumed high levels of caffeine (about 78 mg a day, or the equivalent of one shot of espresso): 54.4 percent did not have AMD and 45.1 percent had AMD....The researchers opted to look at caffeine because it is a powerful antioxidant that is known to be protective against other conditions, such as Alzheimer's disease.