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Notice that the carbon dioxide levels in the air keep rising and rising? Along with the world getting hotter, the carbon dioxide levels are rising, and last year it hit 414.7 parts per million (ppm). This is the highest it has been in at least 800,000 years, and maybe for millions of years! (It's from the burning of fossil fuels.) Soo... the big question is: What will increasingly higher CO2 levels mean for our brains - for our thinking and cognition?

Ever notice that in rooms filled with people, that the air gets stuffier over time? Well, that's the effect of carbon dioxide - as the carbon dioxide levels rise (from us simply exhaling), the air in the room feels stuffier. It can already feel stuffy at 600 ppm. Rooms with people in them (classrooms, office meetings, etc) easily hit over 1000 ppm of carbon dioxide.

Studies suggest that at certain levels of carbon dioxide our thinking gets worse. While study results vary, there does seem to be agreement that "mental processes in the domain of decision making and planning appear to be robustly affected".  And yes, a growing number of studies do find pretty scary results.

For example, one 2016 study that looked at indoor air in office buildings found that: "...seven of nine cognitive function domains tested in a strategic management simulation decreased as CO2 increased. Employee scores were 15 percent lower in a day spent working at 945 ppm, and 50 percent lower at 1,400 ppm." It means that the people weren't thinking all that well as the CO2 levels rose in the air they were breathing.

Research looking at carbon dioxide effects have generally studied the problem as an "indoor pollutant" and used the outdoor air as a comparison. But what happens when the outdoor air of the future is the "high CO2" level studied today?

Some physical effects of rising carbon dioxide exposure in humans: increased CO2 in the lungs, in the blood, and in the brain (which is associated with reduced oxygen and brain activity), increased sleepiness and anxiety (both of which harm cognitive function), and acidosis (lowered blood pH - which leads to symptoms such as restlessness and a rise in blood pressure). One study in juvenile rats found "reduced levels of neuroprotective growth factor", which harmed brain development and impaired learning and memory.

What about babies and children? Developing fetuses? The elderly? The sick?  All unknown. Also, studies looking at effects are short term, but our future (if not changed) will have us exposed to higher and higher levels of CO2 all the time.

Keep in mind that as outdoor carbon dioxide levels rise, indoor levels will also rise.  Think about it - opening a window to let in some fresh air will only give you the CO2 levels in the outside air. If that is high and feels stuffy, that's what you'll get. All the time. Why isn't everyone discussing this issue? 

Excerpts from Robinson Meyer's article at The Atlantic: The Human Brain Evolved When Carbon Dioxide Was Lower   ...continue reading "What Will Rising Carbon Dioxide Levels Do To Our Brains and Thinking Abilities?"

tongue Credit:Wikipedia

Tongue fat? Lose weight and lose tongue fat? A recent study had an interesting finding - overweight people who lost weight improved their sleep apnea symptoms because they also lost fat in their tongues.

It makes sense - obesity is the primary risk factor for developing sleep apnea, and losing weight improves sleep apnea symptoms. In the Univ. of Pennsylvania study, weight loss also resulted in reducing the volume of some soft tissues of the upper airway (pterygoid and pharyngeal lateral wall), which also improved sleep apnea. But loss of tongue fat was the most important reason for sleep apnea improvements.

From Science Daily: Losing tongue fat improves sleep apnea   ...continue reading "Lose Tongue Fat After Losing Weight, and Improve Sleep Apnea"

There may be another unexpected benefit to having a pet dog in childhood - a lower risk of developing schizophrenia later in adulthood. A recent study (conducted in the Baltimore, MD area) found the lowest risk of developing schizophrenia was in individuals who were exposed to a pet dog from birth or before the age of 3. So... early childhood exposure to household pet dogs is best.

On the other hand, there was no significant link between pet dogs and bipolar disorder, or between pet cats and either psychiatric disorder (schizophrenia and bipolar disorder).

Interestingly, the lower risk of schizophrenia in those having a household pet dog before the age of 3 matches research finding a lower incidence of allergies and asthma in those with early childhood exposure to pet dogs (and also pet cats). There could be a number of reasons, but one popular one is that the exposure to the dog microbes  in early childhood influences the child's gut microbes and affects the immune system in a beneficial way.

From Science Daily: Early-life exposure to dogs may lessen risk of developing schizophrenia  ...continue reading "Early Life Exposure To Pet Dogs and Lower Risk of Developing Schizophrenia"

Another great reason to lose weight if you are really overweight (let's be honest, the term is "obese") is a lower risk of two types of skin cancer: squamous cell carcinoma and melanomaObesity is considered a cancer risk, that is, it increases the risk of cancer, and after bariatric surgery there is a lower risk of cancer.

A long-running study in Sweden (Swedish Obese Subjects study) followed 2 groups of obese individuals for 18 years - 1 group received bariatric surgery (2007 persons) and the other group didn't (2040 persons). They found that the group who had received bariatric surgery, along with a large weight loss, had a significantly lower risk of getting squamous cell carcinoma and melanoma  than the group who received conventional "obesity treatment" (such as advice on losing weight).

How much weight did they lose after the surgery? After 2 years the average weight loss in the surgery group was 63.27 pounds (28.7 kg), which leveled off to 47.62 lbs (47.62 kg) by the 15 year follow-up visit. The weight changes in the non-surgery (control) group was small and never exceeded 6.61 pounds in gains or losses.

The researchers give a number of reasons why a large weight loss may be contributing to reduced risk of skin cancer, including leptin uptake changes, lower chronic systemic inflammation, and changes in gut microbes. In summary, they found a 42% lower risk for both forms of skin cancer combined, and 57% lower risk of malignant melanoma in the surgery group (as compared to the non-surgery group).

BOTTOM LINE: If you are really overweight, then try, try, try to lose a big chunk of weight. Your body will thank you in many ways. Not just lower risk of some cancers (including breast cancer), lower risk of diabetes, increased chance of diabetes reversal, lower risk of dementia, lower chronic systemic inflammation, better sperm quality, and on and on.

The CDC says that a person with a BMI (Body Mass Index) of 30.0 or higher is obese, and being overweight is a BMI of 25 to less than 30. [Body Mass Index table]

From Medical Xpress: Lower risk for malignant melanoma after bariatric surgery   ...continue reading "Bariatric Surgery, Weight loss, and Lower Risk of Skin Cancer"

Are you exercising frequently? No? Perhaps you need a good motivating reason. Recent study results provide a good reason (brain health!) for all of us to exercise or do some form of of moderate physical activity for at least 2 1/2 hours per week.

A study conducted in Germany found evidence of an association between cardiorespiratory fitness and brain health, particularly in gray matter volume and total brain volume. The researchers found that higher cardiorespiratory fitness is associated with larger brain volumes in several brain regions that are involved with cognitive functioning.

The study found that exercise (which improves cardiorespiratory fitness) was especially beneficial for older adults. This is because there is some shrinkage of brain volume in normal aging, as well as in some diseases - thus want to prevent brain volume shrinkage as much as possible.

For example, one of the areas of the brain that that had greater volume with cardiorespiratory fitness was the hippocampus. The hippocampus plays a central role in memory-related functions and in stress regulation. This is an important finding because shrinking of the hippocampus (atrophy) is associated with several diseases and disorders, such as Alzheimer disease, depression, and schizophrenia.

What exactly is cardiorespiratory fitness? Cardiorespiratory fitness refers to the ability of the circulatory and respiratory systems to supply oxygen during physical activity. It is a big part of physical fitness and can be improved through regular physical activity, such as exercise. Higher cardiorespiratory fitness is associated with lower risk of heart disease and metabolic syndrome.

Bottom line: Get out and move, move, move to improve your cardiorespiratory fitness and so also benefit the brain. After all, we all want to prevent brain volume shrinkage (and cognitive decline) if at all possible. By the way, other studies also find beneficial brain effects from regular physical activity and exercise, even light physical activity.

...continue reading "Physical Activity Is Beneficial For The Brain"

Drinking drip coffee is healthier than boiled coffee? A study conducted in Sweden suggests that drinking 2 to 3 cups of drip coffee (using a filter) daily lowers the risk of type 2 diabetes, while drinking boiled coffee has no health effect.

The 60% lower rate of type 2 diabetes in drip coffee drinkers (as compared to boiled coffee drinkers) could be due to coffee filters capturing diterpenes - a molecule that is linked to health problems. But the filters still allow beneficial molecules, such as phenolic substances, to pass into the coffee. In other words, preparing the coffee 2 different ways results in coffee with different chemical compositions and properties.

The researchers were able to separate out the 2 types of coffee drinkers simply by analyzing the metabolites in the blood - there were differences in the metabolites (substances made when the body breaks down coffee) of boiled coffee vs drip coffee drinkers.

As a daily coffee drinker, who only uses a drip coffee maker, I am pleased with the results. [Many studies find health benefits from coffee consumption.] But as the researchers note, we need to also look at coffee prepared other popular ways, all of which don't use filters, and so are (maybe) similar to boiled coffee: French press, espresso, percolator, and coffee pods. Will they also have the same effect as drinking boiled coffee?

From Science Daily: Filtered coffee helps prevent type 2 diabetes, show biomarkers in blood samples  ...continue reading "Drip Coffee, But Not Boiled Coffee, Lowers The Risk Of Type 2 Diabetes"

Exercise appears to protect against some cancers. Yes, something so simple as merely getting the recommended amount of 2 1/2 hours per week of exercise (e.g. brisk walks) really lowers the risk of 7 cancers: colon, breast, endometrial, kidney, myeloma, liver, and non-Hodgkin lymphoma.

The researchers analyzed 9 studies for a total of 755,459 individuals (median age 62 years, 53% females) who were followed for 10.1 years, and found that 50,620 cancers developed. They specifically looked at 15 cancers and found that exercise lowered the risk of 7 cancers. Some, but not all, were lowered in a dose response manner, that is, the more exercise, the bigger the protective effect (e.g. breast, colon, endometrial cancer). How much the cancer risk was lowered with exercise varied by types of cancer: colon (8%-14% lower risk in men), breast (6%-10% lower risk), endometrial (10%-18% lower risk), kidney (11%-17% lower risk), myeloma (14%-19% lower risk), liver (18%-27% lower risk), and non-Hodgkin lymphoma (11%-18% lower risk in women).

How much exercise was needed for a cancer protective effect? About 2 1/2 to 5 hours per week of moderate-intensity physical activity, such as brisk walking. The study looked at "leisure-time" exercise, which can include exercise, sports or any recreational activity which is typically "moderate to vigorous intensity".

The Physical Activity Guidelines from the US Department of Health and Human Services recommends that adults do at least 150 to 300 minutes of moderate-intensity physical activity a week, or 75 to 150 minutes of vigorous-intensity activity, or an equivalent combination of moderate- and vigorous-intensity activity. Brisk walking is moderate intensity physical activity. Bottom line: get out and move, move, move!

From Medical Xpress: Report links recommended physical activity levels to lower risk of seven cancers   ...continue reading "Exercise May Lower The Risk Of Some Cancers"

What is the best way for cleaning hands to prevent the spread of flu viruses? Advertisers would have you believe that only their hand sanitizers can do the job, but... guess what? That's not true! Hand washing with soap and water is the best. One study found that even skipping the soap and just rubbing the hands with plain water for 30 seconds is better than most hand sanitizers!

classroom study illustrated nicely how handwashing with soap and water is better than hand sanitizers or doing nothing (dirty hands) in spreading germs. The photos show it wonderfully.

From Medscape: Plain Water Better Than Hand Sanitizer for Influenza A

Simple handwashing — even without soap — is more effective than many hand disinfectants for killing influenza A virus (IAV) in typical clinical situations, new data show.

The researchers say the key factor that determines the effectiveness of ethanol-based disinfectants (EBDs) is whether there is wet mucus surrounding the virus. Wet mucus prevents the disinfectant from reaching the virus, which means the virus remained active after 120 seconds of EBD exposure.

By contrast, washing hands under plain water for 30 seconds inactivated the virus, regardless of whether it was initially surrounded by wet or dry mucus.  ...continue reading "Is Hand Washing Better Than Hand Sanitizers For the Flu Virus?"

Another great option for losing weight and better health may be to only eat within a 10 hour window, and then not eat for 14 hours (thus a nightly 14 hour fast). Many may find this easier than traditional dieting (counting calories and restricting eating). Just eat breakfast later, supper earlier, and no snacks in the evening. (But water is OK.)

Researchers from the Univ. Of California and Salk Institute conducted the 10-hour restricted eating study on persons with metabolic syndrome, most of whom were also on high blood pressure (anti-hypertensive) medicine and statins. After 12 weeks the people had lost weight, lost body fat, lowered blood pressure, reduced cholesterol, and decreased the size of their waist.

Since metabolic syndrome raises the risk for diabetes and heart (cardiovascular) disease, then 10-hour restricted eating can be an important tool to improve health. The researchers point out that in animal studies, time-restricted feeding can prevent and reverse aspects of metabolic diseases, and in healthy humans, it reduces the risks of metabolic diseases. Studies also found benefits with 9-hour restricted eating and 12 hour fasts.

From Science Daily: Clinical study finds eating within 10-hour window may help stave off diabetes, heart disease  ...continue reading "Improve Health and Lose Weight By Restricting Eating To A 10 Hour Window"

Uh-oh, these research findings are not a surprise. A study conducted in 6 U.S. metro areas found that as income levels go up, peer pressure to apply pesticides on lawns increases. As well as to irrigate lawns and apply fertilizers. One can definitely see this in the NYC metro area - the wealthier the neighborhood, the more monochromatic fake-looking lawns. Some even keep their pesticide lawn signs on the lawn for days as a status symbol.

This has an incredibly large environmental impact because lawns can be thought of as the biggest crop in the USA. Lawns cover the most area (ahead of corn) and many lawns have intense chemical management (many have pesticides applied every month for most months of the year). Yikes!

Unfortunately, every year more evidence is accumulating of the harmful health effects of pesticides - in humans, pets, wildlife, water, air, and soil. Harmful effects include neurological and immunological effects, endocrine disruption, cancers, and birth defects. Fertilizers and water irrigation of lawns (sprinkler systems) also have a set of problems, including algae blooms in water and depletion of fresh water resources. [See posts on pesticides.]

And of course, last, but not least, pesticides disrupt the microbial life of the soil, as well as kill insects and worms. I will never forget young children in a classroom being shocked by all the worms found in good soil (in a bucket of organic dirt from my yard) - they had never seen them in their chemically managed yards.

Bottom line: Be a trend-setter in your neighborhood and embrace the natural wildflowers weeds in your lawn. Think of it this way: clover and dandelions can't give you cancer, but pesticides can. In addition, studies find that untreated lawns result in diversity of grasses growing in the lawn and are also important bee habitats for all sorts of bee species. All positive.

From Beyond Pesticides: High Income, Peer-Pressure Correlated With Chemical Intensive Yard Care Practices  ...continue reading "As Income Levels Rise, Chemical Use On Lawns Increases"