Posts tagged with "Mental health benefits"

Cold showers: A scientist explains if they are as good for you as Wim Hof (the ‘Iceman’) suggests

April 28, 2022

Anyone watching the BBC programFreeze the Fear with Wim Hof, may be starting to wonder whether there really is “power in the cold shower” as extreme athlete Hof claims.

Hof, who set a Guinness World Record for swimming under ice, says that a “cold shower a day keeps the doctor away” by decreasing stress and increasing energy levels, Raw Story reports.

He asks celebrity participants on the show to take a cold shower of 12°C (54°F) every day—increasing the duration of the shower over time from 15 seconds to two minutes. Watching the reaction of the participants under the cold shower shows you that it is not a pleasant experience, at least at first.

According to Raw Story, there is not much research looking at the health benefits of cold showers, so the literature is limited. The largest study—conducted among 3,000 participants—was carried out in the Netherlands and found that people who took a daily cold shower (following a warm shower) of either 30 seconds, 60 seconds, or 90 seconds for one month were off work with self-reported sickness 29% less than those who had a warm shower only. Interestingly, the duration of the cold water did not affect the sickness absence.

The reason why cold showers might prevent people from getting ill is still unclear. Some research suggests that it boosts the immune system. A Czech study showed that being immersed in cold water (14°C/57°F) for one hour) three times a week for six weeks, gave a slight boost to the immune system of “athletic young men,” the only group tested. However, further research is needed to fully understand the effects on the immune system.

In the BBC program, Hof suggests that cold water activates the cardiovascular system and therefore improves its function. He says: “We go to the gym to work our muscles, but inside our bodies we have millions of tiny muscles in the cardiovascular system—and we can train them by simply taking a cold shower.”

When you have a cold shower, your heart rate and blood pressure increase. There is some evidence that cold water activates the sympathetic nervous system, which is the part that governs the “fight-or-flight” response (an automatic physiological reaction to an event that is perceived as dangerous, stressful or frightening).

When this is activated, such as during a cold shower, you get an increase in the hormone noradrenaline. This is what most likely causes an increase in heart rate and blood pressure observed when people are immersed in cold water and is, therefore, linked to the suggested health improvements mentioned by Hof.

Cold water immersion also has been shown to improve circulation. When exposed to cold water, the skin blood vessels constrict (get smaller), reducing blood flow. When the cold water stops, the body has to warm itself up, so there is an increase in blood flow as the blood vessels increase in size due to dilation. Some scientists think that this could improve circulation. A study looking at cold-water immersion after exercise found that, after four weeks, blood flow to and from muscles had improved.

In the program, Hof recommends participants to increase the duration of the shower each day. However, the only research study which has explored the duration is the one mentioned earlier from the Netherlands. They found that the length of the cold shower was irrelevant. Therefore, a 15-second cold shower should be sufficient enough to experience any health benefits.

However, there is some danger involved: Having a cold shower can be a bit of a shock. As mentioned above, it also stimulates the flight-or-fight response which increases heart rate and blood pressure. This can have a negative effect for those with heart disease as it could precipitate a heart attack or heart-rhythm irregularities. If anyone has fatty deposits in their arteries, a rapid increase in heart rate could potentially cause some of the deposits to fall off and block the artery leading to a heart attack.

In addition, according to Mike Tipton, an expert on human physiology at the University of Portsmouth, submersion in cold water can be connected to an increase in breathing as well as heart rate. But there is also a “diving response” when submersed in cold water, where the body automatically decreases heart rate and instinctively you stop breathing (in contrast to flight-or-fight responses). This conflict can cause heart rhythm abnormalities and potentially sudden death. However, this is a greater risk with cold water immersion, such as open water swimming, than a cold shower.

Cold showers are thought to have mental health benefits too. However, the Dutch research study found no improvements in anxiety with cold showers. But it may reduce symptoms of depression. The proposed reason for this is that people have a high density of cold receptors on our skin and a cold shower activates them and sends a vast amount of electrical impulses to the brain, which may have an anti-depressive effect.

There has also been research in older adults suggesting that cold water applied to the face and neck is associated with temporary improvements in brain function—including improvements in memory and attention.

So Hof’s claim that a “cold shower a day keeps the doctor away” has some scientific evidence behind it. However, the extent of the health benefits and the exact reasons for it are still to be determined. Caution must be exercised by those who have an existing heart condition.

Research contact: @RawStory

OM can lead to OMG: Meditation is not for everyone

May 15, 2019

Meditation has been touted by millions worldwide for its ability to lower stress, zap anxiety, and increase focus, among other mental health benefits. But a study conducted at the University College of London has found that fully 25% of those who have tried it say that they don’t feel tranquil or serene; rather, they experience fear and distorted emotions, Study Finds reports.

Of 1,232 frequent meditation practitioners (people who have meditated regularly for at least two months) surveyed by researchers at the college, more than one-quarter admit they have had at least one “unpleasant experience” while meditating.

Researchers say suffering from an unpleasant meditative experience seems to be more prevalent among specific groups—among them, those who:

  • Attend a meditation retreat,
  • Only practice “deconstructive types” of meditation such as Vipassana (insight) and Koan practice used in Zen Buddhism, and
  • Experience higher levels of repetitive negative thinking.

Conversely, women and participants with religious beliefs were less likely to have a negative experience.

“These findings point to the importance of widening the public and scientific understanding of meditation beyond that of a health-promoting technique,” says lead author Marco Schlosser, a professor in UCL’s Division of Psychiatry. “Very little is known about why, when, and how such meditation-related difficulties can occur: More research is now needed to understand the nature of these experiences. When are unpleasant experiences important elements of meditative development, and when are they merely negative effects to be avoided?”

For the study, participants were surveyed online about their meditation history, and completed assessments that measure repetitive negative thinking and self-compassion. They were also asked, “Have you ever had any particularly unpleasant experiences (e.g. anxiety, fear, distorted emotions or thoughts, altered sense of self or the world), which you think may have been caused by your meditation practice?”

In all, 25.6% said they’ve had an unpleasant experience (28.5% of men, 23% of women). This was especially true for those who did not have a religious affiliation (30.6%), versus 22% who did hold religious beliefs. About 29% of people who had attended a meditation retreat reported negative experiences, compared to only 19.6% of those who had never attended one.

Researchers say the results show there needs to be a greater focus on the downside to meditating, as studies are typically centered around all the good the practice offers.

“Most research on meditation has focused on its benefits, however, the range of meditative experiences studied by scientists needs to be expanded,” says Schlosser. “It is important at this point not to draw premature conclusions about the potential negative effects of meditation.”

The study findings are published in the May 9 edition of the journal, PLOS One.

Research contact: @ucl