Dr. John Day, Cardiologist

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The 9 Best Ways Saunas Help Your Heart

Diet and exercise can be a hard road for many people trying to protect their hearts.  Based on new science, saunas may be the easiest heart-healthy habit anyone can adopt.  In this article, I’ll review the science and share the nine best ways saunas help your heart that you probably didn’t know about.

My Sauna History

I was not a big fan of saunas.  I always preferred the steam shower or the hot tub to the sauna.

In my youth, I tried the sauna a few times at the local gym.  At that time, it seemed like the sauna was always dominated by older men, wrapped in towels, who read the newspaper in silence.  There definitely was an awkward silence in the sauna at the gym.

As a result, I haven’t been back to a sauna in more than 30 years.  With an ever-increasing number of medical studies advocating the health benefits, I’m starting to wonder if we should put one in our home.

The Sauna Culture in Finland

In contrast, saunas are everywhere in Finland.  Saunas get them through the long and cold winters.  Not only do saunas get them through the winter but saunas may also be one reason why the life expectancy in Finland, without any natural vitamin D for most of the year, has a much longer life-expectancy than what we have in the U.S.

The sauna culture in Finland is also much different than that of a typical U.S. gym.  It is a social event.  Many homes have a sauna.  Families, friends, and neighbors take saunas together.  Rather than the silent sauna experience, these saunas are often lively and fun.

The Finnish Sauna Study

In this study, researchers followed 2,315 middle-age Finnish men (age 42-60) for an average of 20.7 years to see if regular sauna use prevented heart disease and extended life.  Even after controlling for the other cardiac risk factors, the risk of sudden cardiac death was  52% lower in the near-daily sauna users when compared to those who rarely used the sauna.  Also, total mortality was also reduced by 17% in the frequent sauna users.

I should point out that these Finnish saunas are not for the faint of heart.  It is an intense dry heat at temperatures much higher than what we use for saunas in the U.S.  Thus, the results of this study may not apply to the typical U.S. sauna, steam rooms, or hot tubs.

The 9 Best Ways Saunas Help Your Heart

There are many possible ways that saunas help your heart.  Here are nine of them:

1. Stress Reduction

It is hard to take your stress into the sauna.  Saunas offer a great way for both physical and mental relaxation.  As we have discussed in many previous articles, stress is one of the biggest factors in heart disease.

2. Social Connection

Connecting socially with friends and families may be the secret to a long and healthy life.  Indeed, studies have shown that social connection may be the most important factor in cardiac health and longevity.

3. Saunas Mimic Exercise

Daily exercise is one of the most important things you can do for your heart.  Saunas have to be the simplest way to “exercise.”

Both exercise and saunas result in “heat training” to the body.  Indeed, with sauna therapy, you can often see a marked heart rate response.  A heart rate of 150 beats per minute is not unusual for many sauna users in Finland.

4. Saunas Lower Blood Pressure

The sauna’s heat dilates and relaxes blood vessels.  This results in significant blood pressure lowering.

Of all the ways you can protect your heart, blood pressure lowering is one of the best.  And this blood pressure lowering effect from the sauna can up to two hours.

5. Improved Exercise Tolerance

Saunas may benefit skeletal as well as cardiac muscle.  Indeed, studies have shown that heat training improves exercise tolerance and speeds muscle recovery after injury.

6. Better Glucose Control/Less Diabetes

Through the effect on skeletal muscles, saunas improve insulin sensitivity.  As your insulin sensitivity improves, glucose metabolism normalizes, and the risk of diabetes becomes a non-issue.

7. Improved Cognitive Function Through BDNF

Sauna use has also been shown to increase brain-derived neurotrophic factor (BDNF).  BDNF is like fertilizer for our brains.  Indeed, increased BDNF can improve cognitive function and memory.  To learn more about BDNF, please read my article on BDNF.

8. Improved Lung Function

For hundreds of years, Finnish doctors have recommended sauna use for patients suffering from lung conditions.  Indeed, some studies even suggest improved respiratory function with regular sauna use.

9. Longevity

As was seen with the Finnish sauna study discussed in this article, saunas and a longer lifespan go hand in hand.  This is likely due to increased expression of heat shock proteins and FOXO3 through heat training.

Heat shock proteins are specialized proteins that repair damaged proteins and waste protein accumulation in our bodies.  Chronic diseases, like cardiovascular disease and Alzheimer’s Disease, result in progressive protein degradation or accumulation.

Heat training, through exercise, also increases expression of heat shock proteins.  Also, centenarians tend to have increased expression of heat shock proteins as well.  We have found that the long-lived people in China’s Longevity Village also have increased expression of heat shock proteins.  Heat shock proteins are repair proteins that are required for a healthy and long life.

In addition to heat shock proteins, heat training and exercise also increases expression of the FOXO3 gene.  FOXO3 gene expression enhances DNA repair.  Once again, people with the highest levels of FOXO3 expression are the people most likely to live a long and healthy life to 100+.

The Risks of Saunas

Saunas are certainly not without risk.  A heart rate of 150 bpm in someone with a preexisting heart condition could trigger a heart attack.  Also, severe dehydration, combined with electrolyte depletion, could trigger a cardiac arrest.

If you want to enjoy the possible health benefits of saunas, it needs to be done wisely.  To begin with, it is always best to consult with your physician first.  Also, make sure you are well hydrated and that your electrolytes are tanked up prior to entering the sauna.  When first using the sauna make sure you limit your time in the sauna.

You also need to be very careful if you are on blood pressure medications.  The blood pressure lowering effect of saunas, in combination with blood pressure medications, could cause you to pass out.

Alcohol consumption has no place in the sauna. Indeed, based on a Swedish study, 71% of all sauna deaths involved alcohol.  It also may not be a bad idea to use the “buddy system” in the sauna as well.

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10 Ways to Boost Brain Function with BDNF

Did you know that you have a 1 in 3 chance of developing Alzheimer’s Disease or another form of dementia? Is there a way to boost brain function now and prevent dementia later in life?

The solution may be to raise your BDNF levels. In this article I will share with you 10 ways to boost brain function naturally with BDNF.

What is BDNF?

Brain derived neurotrophic factor (BDNF) is a protein which can be thought of as “brain fertilizer.” BDNF helps the brain to develop new connections, repair failing brain cells, and protect healthy brain cells.  Having enough BDNF around can protect our brains from neurodegenerative diseases like Alzheimer’s Disease and Parkinson’s Disease.

When BDNF levels are high, acquiring new knowledge is easy, memories are retained, and people feel happier.  Indeed, BDNF can even be thought of as a natural anti-depressant.

Unfortunately, when BDNF levels fall the opposite occurs. People have difficulties learning new things, Alzheimer’s Disease and other forms of dementia occur, and depression is much more common.

Clearly we want more BDNF!

Airplane Pilots and BDNF

As we age our BDNF levels naturally fall and we may find it more difficult to do the complex tasks that were much easier for us when we were younger.  Perhaps this explains why your parents or grandparents may not feel as confident driving a car as they did when they were younger.

Even worse, about 1 in 3 Americans have a mutation in the gene coding for BDNF so that in these people BDNF levels fall much faster than they should with age.

A few years ago Stanford University researcher, Dr. Ahmad Salehi and his colleagues, wanted to know just how well these people with genetically lower levels of BDNF with aging functioned with complex tasks over time.

To better understand this question, they designed a study whereby they had 144 airplane pilots, ages 40-69, perform an annual flight simulator test at Stanford University over at least a 3 year period of time. They found that in the pilots without the mutation that their scores and BDNF levels just slightly decreased over time.  However, in the pilots who had the mutation causing a much faster drop in BDNF levels with age, their scores on the flight simulator test dropped twice as fast as those without the mutation.

The message of this study is that BDNF levels naturally decrease with age.  However, for the 1 in 3 people with the mutation in the gene coding for BDNF, their BDNF levels will fall precipitously with aging making complex tasks very difficult to perform.  Thus, if we want to maintain or enhance brain function as we age we will need to do everything possible to keep BDNF levels high.

Turn Old Brains Into Young Brains with BDNF

To reverse the effects of decreased BDNF on aging brains, researchers in Brazil had an interesting idea. What would happen if they put old rats into an exercise program. Could they then increase the BDNF levels and brain function of these old rats with an exercise program?

After 5 weeks of just mild intensity exercise for these old rats, Brazilian researchers were able to show that exercise reversed the age related cognitive decline. Specifically, this exercise program significantly increased BDNF levels and the old rats learned faster and their memory was improved.

While it is hard to extrapolate the findings of these 35 old female rats used in this study to humans, there is still a lesson to be learned here. By getting the old sedentary female rats to start running for 15 minutes 4 days of the week on a rat treadmill their brain function improved so much that it was almost as good as the young rats.

The key message of this study is that even short periods of exercise can have a dramatic effect on BDNF, learning abilities, and memory strength.

Exercise Boosts BDNF and Cognitive Function in the Young as Well

The beneficial effects of BDNF are not just for old brains. Even young brains seem to benefit as well.

To test this hypothesis, Irish researchers designed a study whereby they coaxed sedentary male college students to start exercising.  In this study, they wanted to see what the effects of an exercise program would be on BDNF and memory abilities.  As these were young college students, researchers pushed them much harder on the stationary bicycle than the old Brazilian rats were pushed on the rat treadmill in the previous study.

This high intensity exercise boosted both the BDNF levels and memories of these young college students.  Once again, the message is clear.  Exercise improves BDNF and brain function in both the old and the young.

BDNF is Critical for a Healthy Heart

BDNF’s effects are not just on learning and memory.  BDNF is also critical for a properly functioning heart.

In a recent study from Johns Hopkins University, Dr. Ning Feng and colleagues, genetically created a mouse that lacked BDNF receptors on the heart.  In other words, they altered the genomes of these mice so that their hearts could not sense BDNF from the brain at all.

Interestingly, researchers found that in these mice hearts without the influence of BDNF that they quickly developed heart failure.  Even though this study was done it mice, it does raise the question of whether heart failure, which is common in the elderly, may also be a function of declining BDNF levels.

It is well known that depression is a common cause of heart disease.  People that are depressed also tend to have much lower levels of BDNF.  Could the link between depression and heart disease be due to low levels of BDNF?

BDNF May Control Our Lifespan

Researchers are now speculating that BDNF could be one of the key regulators of our lifespan.  Indeed, studies have shown that BDNF is closely correlated to lifespan.  BDNF may just be how our brains control our lifespan.  Could BDNF represent the sand in an hourglass in that when the BDNF is gone our lives are over?

10 Ways to Boost Brain Function with BDNF

By this point in the article it is pretty clear that for optimal brain and heart function we want more of this substance around.  How can we increase BDNF levels beyond just exercise?  Let me give you 10 scientifically proven ways to raise BDNF levels.

1. Exercise

Exercise is the very best way to boost BDNF levels.  As seen from the studies already discussed in this article, even short bursts of exercise can dramatically raise BDNF.  We must create a lifelong habit of exercise to keep our brains and hearts functioning optimally.

2. Avoid Sugar, Processed Foods, and HFCS

Just as exercise can raise BDNF levels, sugar, processed foods, and high fructose corn syrup (HFCS) all do the exact opposite.  Many studies have now shown that rats fed the Standard American Diet (SAD), which is high in sugar, bad fats, and HFCS, have lower levels of BDNF.  These lower levels of BDNF from the Standard American Diet result in rats which are not as smart and have memory difficulties.  Clearly, for optimal brain function we have to eat the right foods to increase BDNF levels.

3. Intermittent Fasting

Interestingly, there is a growing body of data that time restricted feeding, or intermittent fasting, may also increase BDNF.  Intermittent fasting is merely the act of resting our guts periodically which then triggers a cascade of hormonal events in our bodies which boost our body’s repair mechanisms.

Intermittent fasting does not have to be hard.  Studies show that even fasting as short as 12 hours can have a beneficial effect. To fast for 12 hours is really as simple as skipping that pre-bedtime snack and not eating again until breakfast the next day.  To learn more about the role of intermittent fasting please read my article Intermittent Fasting, Weight Loss, and Longevity.

4. Mental Stimulation

Exercising our brains with mental stimulation also increases BDNF.  Like everything else, the old adage “use it or lose it” also applies to the brain.

5. Eat Oily Fish

Recent data have shown that a diet high in omega 3s can improve BDNF levels and boost brain function.  Unfortunately, studies also show that up to 95% of Americans are deficient in the omega 3 fatty acids.

The best studied way to get more omega 3s is to include oily fish in your diet.  My favorite way to do this is with the very affordable wild Alaskan salmon that we buy at Costco.

While there are certainly non-fish forms of omega 3s, like those found in walnuts, chia seeds, flax seeds, etc., these have not been studied as well and may not be as critical as the DHA and EPA forms of omega 3s found in oily fish.

Fish oil supplements can certainly boost omega 3 levels in the body.  However, omega 3s, in the form of fish oil supplements, can easily go rancid, they may increase the risk of prostate cancer, and they may even accelerate heart disease and dementia in the 25% of the American population that carries the ApoE4 gene. Thus, given these concerns with fish oil, I recommend that my patients try to get their omega 3s from real fish sources.

6. Be with Family and Friends

Close nurturing relationships have been shown to boost BDNF.  These are the relationships that come from real friendships or spending time with family members.

7. Get Some Sun

Even something as simple as getting some sun each day can boost BDNF levels.  Look for opportunities to get out of your home or your office building and feel some of the sun’s healing effects each day.  Of course, one always has to be sun smart to avoid skin cancer.

8. Eat More Curry/Turmeric, Red Grapes, and Blueberries

Curcumin, which is found in turmeric and to a lesser extent in curry, has been shown in to increase BDNF and can even prevent Alzheimer’s Disease.  Learn to use these spices with the foods you make to protect your brain.

Do you like red grapes?  If so, you may just be in luck.  Resveratrol, found primarily in red grapes, has also been shown to boost BDNF levels.  If red grapes aren’t your thing then the anthocyanin in blueberries have also been shown to raise BDNF levels.

9. Do Something to Reduce Stress

Managing stress is key to optimal health.  BDNF is no exception.  People who are under a lot of stress produce less BDNF.  Could this be why people often don’t think as clearly when they are feeling very stressed?

Stress is a part of modern life.  Find something, anything, that you can do each day that helps you to keep life in perspective and allows you to unwind mentally.

10. Get At Least 7 Hours of Sleep

As with stress, sleep is critical for health.  As you might expect, BDNF is reduced with sleep deprivation.  If you struggle with getting at least 7 hours of sleep, like me, this study suggests that regular exercise can help to keep BDNF levels up even if your sleep is compromised.

What do you do to keep your BDNF levels up and your brain and heart functioning optimally?

Disclaimer

Please do not self diagnose or treat based on anything that you have read in this article.  Also, if you are considering changing your exercise program or diet, please discuss this with your physician first.