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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.]

Dental floss coated with a "non-stick coating" has long been a concern of mine. Do the Teflon-like chemicals get into the person when a person is flossing teeth? These chemical compounds (called per- and polyfluoroalkyl substances or PFASs) are linked to health problems (e.g. kidney and testicular cancer, semen quality, thyroid disease, immune system effects, and lowered sex and growth hormones in children) - so you want to avoid them if possible. Well, it turns out these chemicals are shed into the person's mouth when flossing and can be measured in a person's blood. Bottom line: avoid non-stick smooth dental floss such as Oral-B Glide dental floss (or when the dental floss label brags that it is similar to Glide dental floss). Use plain waxed or unwaxed floss instead.

Per- and polyfluoroalkyl substances (PFASs) are a group of chemicals used in a wide variety of consumer products because they have water- and grease-resistant properties. They are used in nonstick cookware, in food packaging (especially the paper wrappers and cardboard containers) , stain-resistant carpets, furniture, floor waxes, textiles, water-proof and stain-resistant clothing (such as Gore-tex fabric), and performance gear. How do they get into us? Some ways: the chemicals can migrate out of food packaging into food, or can be released into the air and dust from carpets and upholstery treated with stain-resistant coatings. PFASs have been detected in water, soil, and in the bodies of almost all Americans!

This study (and others)  found that higher levels of  these chemicals in the body occur with the following: frequent consumption of prepared food in coated cardboard containers, having stain-resistant carpets or furniture, using Oral-B Glide dental floss, and living in a city served by a PFAS-contaminated water supply. It may not be possible to totally avoid all PFASs, but one can lower exposure to them (for example, don't have stain-resistant carpets in the house or apartment, and try to eat less fast-food). From Medical Xpress:

Dental flossing and other behaviors linked with higher levels of toxic chemicals in the body        ...continue reading "Some Types of Dental Floss Should Be Avoided"

Another study finding more benefits of exercise was recently published in the journal Neurology. The study by researchers at Duke University found that in older adults who were already experiencing  cognitive (thinking) problems, but did not have dementia - that after just 6 months of exercise they showed improvements in thinking. What were their original thinking problems? The individuals had difficulty concentrating, making decisions, or remembering, but it was not severe enough to be diagnosed as dementia. However, these persons were considered at risk for progressing to dementia.

The 160 individuals in the study were 55 years or older (mean age 65), mainly women, evenly divided between whites and minorities, were sedentary (didn't exercise), and had heart (cardiovascular) disease or were at risk for heart disease. They were randomly assigned to one of 4 groups: 1) aerobic exercise (with no dietary changes), 2) DASH diet (with no exercise), 3) DASH diet plus exercise, and 4) the control group, who had no dietary or exercise changes - they just received some educational phone calls. The study lasted 6 months, and there were no drop outs.

In the study, the aerobic exercises were done 3 times per week: 10 minutes of warm up exercises followed by 35 minutes of continuous walking or stationary cycling. The Dietary Approaches to Stop Hypertension or DASH diet is a heart healthy diet that emphasizes eating fruits, vegetables, whole grains, as well as fish, poultry, beans, and nuts. It stresses lowering the intake of salt (sodium), sweets, sugar sweetened beverages, and fatty foods (both trans fats and saturated fats). [Note that in many ways it's similar to the Mediterranean diet with its emphasis on fruits, vegetables, whole grains, legumes, seeds, nuts, and lowering intake of meat. Studies find cognitive benefits from the Mediterranean diet.]

The six months of exercising improved thinking skills called executive function - in both the exercise alone or exercise + DASH diet group. The largest improvements were in the exercise + DASH diet group (as compared to the control group, which actually showed decline in functioning). Executive function is a person's ability to regulate their own behavior, pay attention, organize and achieve goals, and was measured in this study with a group of cognitive tests (a "standard battery of neurocognitive tests"). These executive function improvements did not occur in the DASH diet alone group or the control group. The study found no improvement in memory or language fluency in any of the groups. The exercise alone, DASH diet alone, and the combined exercise and DASH group had other health benefits by the end of the study, for example they lowered their risk factors for heart disease. Other improvements: the exercise groups had improvements in insulin levels, and the DASH groups decreased their intake of blood pressure medicines.

To illustrate how amazing these results are: at the start of the study (baseline) all participants scored as if they were in their early 90s on cognitive tests - as if they were on average about 28 years older than their actual chronological age! Then at the end of 6 months, the persons in the exercise + DASH diet showed an improvement of almost 9 years on the tests. In contrast, the control group showed an approximately 6 month worsening performance. When researchers looked at physical markers of the exercisers, they found that physical improvements and improvements in heart disease risk factors (e.g. losing weight, lowering blood pressure) were correlated with executive functioning improvements.

Other studies have found related findings, such as higher physical activity and a Mediterranean diet is associated with lower levels of dementia. The researchers point out that there is growing evidence that combining several lifestyle factors (e.g., exercise, not smoking, a healthy diet, lowering salt intake) and not just exercise alone, has the best results for better cognitive functioning among older adults. Bottom line: eat a diet rich in fruits, vegetables, whole grains, seeds, nuts and get exercise. Walking briskly, gardening, housework, walking up stairs - it all counts.  ...continue reading "Can Exercise and Dietary Changes Help Older Adults With Thinking Problems?"

Once again, a study found health benefits from exercise. This time a large review of studies found that the blood pressure lowering effect of exercise for persons with high blood pressure (hypertension) appears to be similar to that of commonly used blood-pressure (antihypertensive) medications. The study was designed to compare the effect of exercise and medications on systolic blood pressure (greater than 140 mmHg). Unfortunately no study directly compared the two, but the researchers were able to draw conclusions from 391 studies that had used randomly controlled trials (people assigned randomly to different conditions).

The American and UK researchers found that all programs of exercise and all blood pressure medications lowered blood pressure. They did find greater reductions in blood pressure in taking blood pressure lowering medications vs just exercise ("structured exercise regimens"), but pointed out that when studies just focused on people with high blood pressure (instead of everyone), then the results looked more impressive. Meaning the higher the blood pressure, the more effective the exercise.

Other findings: They did not observe a dose-response relationship between exercise intensity and blood pressure reduction. They found that even low-intensity exercise may be effective in reducing blood pressure. The researchers stressed the need for studies that directly compare  exercise programs to blood pressure medications, but point out that pharmaceutical companies are the ones doing the vast majority of studies and they don't have any incentive to do such a study (it could mean the loss of profits from medicines!). Many of the studies compared blood pressure medicines + exercise vs just blood pressure medicines. Thus the researchers said the topic of exercise and blood pressure is currently under studied.

Bottom line: get out and move, move, move for your health! All activity and movement is better than none. Yes, it's easier to just take daily pills, but all medications have side-effects and cost money. Exercise is free and the health benefits are many. Some health benefits of exercise from other studies: lowers blood pressure, lower risk of heart (cardiovascular) disease, lower the waist circumference (get rid of belly rolls!), and lowers triglyceride levels (in the blood).

From Science Daily: Exercise may be as effective as prescribed drugs to lower high blood pressure

Exercise may be as effective as prescribed drugs to lower high (140 mm Hg) blood pressure, suggests a pooled analysis of the available data, in what is thought to be the first study of its kind, and published online in the British Journal of Sports Medicine.   ...continue reading "Can Exercise Be As Effective As Blood Pressure Medications In Lowering Blood Pressure?"

The results of a recent study by Vanderbilt University may help explain why some people have difficulty raising their low vitamin D levels - it may be that their magnesium levels are low. It appears that magnesium may regulate vitamin D levels - when vitamin D levels are low, magnesium supplementation raises vitamin D levels, and when vitamin D levels are high, magnesium supplementation lowers them to a normal level.

What are good food sources of magnesium? Magnesium is found in many plant and animal foods and beverages. Good sources of magnesium include green leafy greens, legumes (beans), whole grains, nuts, dark chocolate, and fatty fish such as salmon. Foods containing dietary fiber generally provide magnesium. By the way, dietary surveys of people in the United States consistently show that intakes of magnesium are lower than recommended amounts. From Medical Xpress:

Study shows magnesium optimizes vitamin D status

A randomized trial by Vanderbilt-Ingram Cancer Center researchers indicates that magnesium optimizes vitamin D status, raising it in people with deficient levels and lowering it in people with high levels

...continue reading "Magnesium Regulates Vitamin D Levels In the Body?"

Once again a study finds health benefits from consuming a Mediterranean style diet - a diet rich in fruits , vegetables, whole grains, nuts, seeds, legumes (beans), olive oil, and fish. The US Women's Health Study involved almost 26,000 women who were healthy at the start of the study and were followed for up to 12 years. The researchers found that a higher consumption of a Mediterranean style diet was associated with about a 28% lower risk in cardiovascular disease events (heart attack, stroke, coronary arterial revascularization, cardiovascular death). Based on what they generally ate, they were classified as having a low, middle, or upper intake of a Mediterranean style diet.

From Medical Xpress: Researchers explore what's behind Mediterranean diet and lower cardiovascular risk

A new study by investigators from Brigham and Women's Hospital, Harvard Medical School, and the Harvard T.H. Chan School of Public Health offers insights from a cohort study of women in the U.S. who reported consuming a Mediterranean-type diet. Researchers found about a 25 percent reduction in the risk of cardiovascular disease among study participants who consumed a diet rich in plants and olive oil and low in meats and sweets. The team also explored why and how a Mediterranean diet might mitigate risk of heart disease and stroke by examining a panel of 40 biomarkers, representing new and established biological contributors to heart disease.   

...continue reading "Mediterranean Diet and Heart Disease"

For years we've been told (and learned in school) that 98.6 degrees Fahrenheit is the normal body temperature of humans. But... it turns out it's not. It's actually a bit lower - closer to 97.7 degrees F. It's the lowest around 6:00 in the morning - 97.5 degrees, and it is highest around 4 to 6 pm - 98.5 degrees F. Women tend to be about 0.2 degrees warmer than men. These were the findings of a crowdsourced smartphone study (with 329 people participating) by researchers at Boston Children's Hospital.

It turns out that other research has also said this for 2 decades. Huh? And yet the outdated 98.6 degree temperature persists in our culture. From Scientific American:

Normal Body Temperature Is Surprisingly Less Than 98.6

Normal body temperature is 98.6 degrees Fahrenheit, right? Not so. There is no baseline for humans, and even if there was, it would be closer to 97.7 °F. Temperature also varies across the day, peaking in late afternoon and bottoming out in early morning. It is slightly higher for women than for men as well. For two decades research has debunked the benchmark, set way back in 1868, yet it persists. One important ramification, says Jonathan S. Hausmann, a rheumatologist at Boston Children's Hospital, who led the latest study, is to redefine fever. Most doctors use 100.4 °F or higher, but if “normal” is lower, then the fever threshold should be, too. It also should vary with the daily pattern and be tailored to each individual, Hausmann says: “A child at 99.0 °F at 4 A.M. may be highly abnormal but at 4 P.M. could be within normal limits.” ...continue reading "Our Fluctuating Body Temperature Is Lower Than 98.6 Degrees"

Another reason to eat fruits and vegetables daily - cognitive and memory functioning in later life. A large US study of 27,842 men found that a higher intake of fruits, vegetables, and orange juice for many years is linked to a lower risk of poor cognitive functioning in later years of life (70s and beyond). The study specifically looked at subjective cognitive function - a measure of earliest changes in cognitive functioning, including memory. This is the stage before "mild cognitive impairment". The study started in 1986 when the average age was 51 years, and continued till 2012. The men studied were all health professionals (e.g. dentists)

What was a high intake of fruits and vegetables? For vegetables: about 5.7 servings per day (while the lowest intake was 1.7 servings per day). For fruit: high intake was 3.1 servings per day (vs lowest intake was .5 servings per day). For fruit juice (orange juice): high intake was 1.5 servings per day (vs lowest intake was .1 servings per day). A serving of fruit is considered one cup of fruit or ½ cup of fruit juice. A serving of vegetables is considered one cup of raw vegetables or two cups of leafy greens.

The researchers found that green leafy vegetables, carotenoid-rich vegetables (esp. tomatoes and peppers), cantalope, berries, and orange juice to be especially protective. They point out that many antioxidant nutrients and bioactive substances (including vitamins A,B, C, and E, carotenoids, flavonoids, and polyphenols) are all found naturally in vegetables, fruits, and juices. These are thought to reduce brain oxidative stress, improve cognitive performance, and to prevent neuronal damage. In other words, all good things for the brain. From Science Daily:

Orange juice, leafy greens and berries may be tied to decreased memory loss in men

Eating leafy greens, dark orange and red vegetables and berry fruits, and drinking orange juice may be associated with a lower risk of memory loss over time in men, according to a study published in the November 21, 2018, online issue of Neurology, the medical journal of the American Academy of Neurology.  ...continue reading "Eat Fruits And Vegetables Every Day!"

In the US and other developed countries it is generally accepted that blood pressure increases with age -  that a blood pressure rise starts in childhood and that it's a normal part of aging. However, a new study found that this is not true - a South American rainforest tribe (the Yanomami) who do not eat a western diet (at all!) and have an active lifestyle, have the exact same blood pressure throughout life. This was true for all the individuals studied - from age 1 to 60. A nearby village of the Yekwana tribe have some western influences on lifestyle and diet, had the same low blood pressure in childhood, but showed increases with age.

The researchers feel that a Western diet and lifestyle play a role in the blood pressure increasing over the life span. They are now looking at the gut microbes of the two tribes to see what role they have in these blood pressure differences. Bottom line: get off your butt  and get active, and eat a high fiber, whole food diet (to feed the beneficial microbes) -  and avoid highly processed foods if you can. Easier said than done. From Science Daily:

Study of two tribes sheds light on role of Western-influenced diet in blood pressure

...continue reading "Blood Pressure Doesn’t Always Increase With Age"

Whoa.... a recent study examined food microbiomes (community of microbes) of some foods and found that the foods contained many species of microbes - hundreds of species! The foods examined were a variety of masala spice mixes, cilantro, smoked salmon, cucumbers, and mung bean sprouts. Other studies have also found large numbers of bacterial species in all sorts of foods, including raw fruits and vegetables, cheeses, and fermented foods, such as kimchi. There are also bacterial differences between conventional and organic foods. No wonder it's good to eat a diverse diet - all those microbes that you're ingesting! A diverse gut microbial community in humans is considered healthy by researchers.

The researchers (all associated with the US FDA - Food and Drug Administration) looked at the bacterial "species richness" (number of different bacterial species) normally found on the 5 types of foods. They used modern genetic sequencing methods to analyze the food microbiomes and found a LOT of bacterial species ("high bacterial diversity"), as well as species unique to the different foods sampled - whether animal or plant based foods. They found not only beneficial species, but also species associated with food spoilage. Every food had some bacteria that could eventually lead to food spoilage (which makes sense - eventually all foods can spoil). Also, how the food was handled and packaged, as well as moisture levels, influenced the bacterial species found in the foods.

The masala spice mixes were especially rich in bacterial species (from from 968 to 1097) and in unique species (19), but the mixes also contained as many as 17 ingredients. Cucumbers had between 227 and 423 bacterial species, and 216 to 573 species for cilantro. Smoked salmon samples had fewer species - ranging from 89 to 181 species. An example of the diversity is that the cucumber microbiome is comprised of species within Proteobacteria (45 to 85%), Firmicutes (2 to 40%), Actinobacteria (8 to 31%), and Bacteroidetes (0 to 2%).

I don't know if one can ever replenish all the bacteria lost from years of antibiotics (e.g. for sinus infections - both chronic and acute sinusitis), but this is a good reason to eat a variety of foods - for all the species of bacteria. These bacterial species are not found in general probiotic pills - one must eat the foods to ingest the variety and richness of microbes. The researchers wrote: "Once established, the most likely source of new microbes joining our GI microbiome is the food we eat: each food stuff and commodity we consume likely contains a microbiome that passes through our bodies while nutritional ingredients and components are digested."

It is unknown how many of these microbes stick around in our body, but lots of research finds that a diet rich in fruits, vegetables, whole grains, seeds, nuts, legumes, some fish and meat (including poultry), some dairy - are beneficial to our gut microbiome, along with numerous health benefits. The fiber in these foods is also beneficial in that it feeds beneficial microbes. [see category NUTRITION for research, also Feeding Your Gut Microbes page.]

Excerpts from research by Karen G. jarvis et al in Frontiers In Microbiology:

Microbiomes Associated With Foods From Plant and Animal Sources

...continue reading "Common Foods Contain Hundreds Of Diverse Bacterial Species"