August 31, 2016
We know that exercise is tied to a lot of health benefits and that besides helping the rest of the body, exercise also improves the brain’s health and strength in many different ways ranging from learning skills and focus to memory and combating stress.
A new study from the US Government’s National Institutes of Health helps explain one aspect of the benefits that exercise provides to the brain. The study reported that skeletal muscle cells secrete a protein, Cathepsin B, in higher quantities for people who exercised regularly on a treadmill.
Researchers reported that an increase in blood Cathepsin B levels corresponded to an improved performance in visual memory tests for humans and that it also resulted in improved performance for mice in spatial memory and maze navigational skills.
Exercise resulted in increased muscle production of Cathepsin B and increased secretion of this protein into the bloodstream and researchers also used mice to verifiy that this protein was able to cross the blood-brain barrier and thereby influence the brain. In other studies, elevated levels of Cathepsin B have been observed in some ailing people (e.g. cancel patients), however, it is unclear whether the elevated levels were due to the body’s attempt to combat the ailment or whether it was due to other reasons.
The recent studies demonstrate that exercise leads to increased levels of Cathepsin B and that this is directly linked to improved brain performance for healthy people. It isn’t easy to figure out every detail about the brain, but this study on exercise, Cathepsin B and the brain helps improve our understanding on how the brain benefits from exercise.
July 4, 2016
Conventional wisdom says that dieting is essential to weight loss and that exercise alone is generally insufficient for weight loss.
However, a new study looked at a related topic – preventing weight gain. This study compared three groups of obesity-prone rats. The control group was sedentary. The second group of rats exercised regularly in running wheels. The third group of rats was sedentary and on a calorie-restricted diet. All three groups ate the same kibbles though daily servings for the calorie-restricted group were 20% less than that for the group of runners.
Unsurprisingly, the control group turned out to be obese at the end of the study. The other two groups staved off obesity. However, the runners were metabolically healthier in terms of insulin sensitivity, cholesterol, burning more fat and they also seemed to have more metabolic activity within their brown fat. Interestingly, gut microbes in the runners were different from gut microbes in the calorie-restricted group, so exercise had a probiotic effect even though all groups had been fed the same kibbles.
This study suggests that exercise alone can deliver results that are far superior to dieting alone – at least for rats trying to avoid obesity. It seems reasonable to assume that this would be true for humans too, though it is obviously important to focus on both exercise and calorie intake while eating healthy food.
June 28, 2016
There are a number of good reasons to eat dark chocolate. I myself try to eat dark chocolate every day. So it was interesting to read a recent study which suggests that “people who eat chocolate at least once a week tend to perform better cognitively“. The researchers say that eating chocolate helps the brain with regular tasks like “remembering a phone number, or your shopping list, or being able to do two things at once, like talking and driving at the same time”
Interestingly, the study doesn’t limit benefits to dark chocolate and that suggests that eating regular chocolate (e.g. milk chocolate which accounts for around 85% chocolate sales in the US) might also help the brain. However, I’ve headlined this post with “dark” chocolate because it seems more likely (from a lot of other research) that cocoa flavanols found in dark chocolate are responsible for improved brain function.
June 22, 2016
An interesting report notes that when you sleep in a new place, only half your brain gets a good night’s rest.
The left side of the brain stays alert when sleeping in an unfamiliar place for the first night. Researchers found that playing irregular beeping sounds into the right ear (thereby stimulating the left hemisphere) is much more likely to wake up a person than playing the same sounds into the left ear (and stimulating the right hemisphere).
This has been described as a first-night-only phenomenon because it only happens when a person is sleeping in a new place for the first time. Presumably, this behavior of the brain is an evolutionary adaptation that happened in an ancient time when humans sleeping in a new place were at risk of being attacked by predators and needed to be on alert.
June 21, 2016
Walking is tied to a number of health benefits and should (almost) always be encouraged. That is why we created a pedometer app to track steps. However, anecdotally, many of us would agree that walking in a natural environment is generally a more pleasant experience than other walking. From my own experience in walking in cities and towns across four continents and natural environments across five continents, I can relate to Henry David Thoreau who said “I think that I cannot preserve my health and spirits, unless I spend four hours a day at least – and it is commonly more than that – sauntering through the woods and over the hills and fields, absolutely free from all worldly engagements.” even though I myself don’t walk four hours a day in any environment, let alone walk in nature for four hours.
Given anecdotal experience with walking in nature, it is interesting to see that medical science can now use data to explain the neurological mechanisms of how walking in nature helps the brain. A Stanford study establishes that cerebral blood flow and neural activity in the subgenual prefrontal cortex (sgPFC) is decreased for nature walkers and not for urban walkers. Self-reporting from the walkers also showed that nature walkers ruminated less. I first heard about this study from a column that explains the Stanford study for a wider audience
The sgPFC (or Brodmann Area 25, BA25) plays a major role in depression and decreased neural activity in this area can help prevent depression and combat stress. Since walking in nature helps the brain (specifically the BA25 region) and decreased rumination/brooding helps reduce stress, the results of the Stanford study strongly suggest that walking in nature can change the brain in ways that help mental health, improve mood and reduce the chances of depression.
Clearly, walking in nature is not a viable option for all people in all circumstances. Health conditions, weather conditions or concerns about some wild animals, criminal humans etc. may dissuade some people from walking in nature. However, for those who enjoy walking in nature and for those who’d like to consider it, studies seem to establish that walking in nature can impact the subgenual prefrontal cortex in ways that are good for the brain.