Dr. Bhatnagar is Professor of Medicine and Distinguished University Scholar at the University of Louisville, Kentucky, USA. He is the Director of the Christina Lee Brown Envirome Institute and Co-Director at the American Heart Association.  He was the Deputy Editor of Circulation Research for 10 years. He was the recipient of the President’s Award for Outstanding Scholarship, Research and Creative Activity, University of Louisville, and Partner in Healthcare Award – Contributing to Greater Louisville Healthcare Community.

Dr. Bhatnagar a leading expert on the mechanisms by which environmental exposures such as air pollution affect cardiovascular disease risk. His studies at University of Louisville have led to the development of the new field of Environmental Cardiology. Dr. Bhatnagar has published 389 peer-reviewed manuscripts, 25 book chapters and reviews and over 200 abstracts. 

Follow @UofLEnvirome on Twitter https://twitter.com/UofLEnvirome

• Pick up “Environmental Cardiology: Pollution and Heart Disease (Issues in Toxicology)” by  Dr. Aruni Bhatnagar https: amazon.com
• University of Louisville Christina Lee Brown Envirome Institute https://enviromeinstitute.com/
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• Ambitious Louisville study seeks to understand impact of trees on our health. (2019, December 12). PBS NewsHour; PBS NewsHour. https://www.pbs.org/newshour/show/ambitious-louisville-study-seeks-to-understand-impact-of-trees-on-our-health 
• ‌Wood, J. (2019, November 21). Re-greening: can Louisville plant its way out of a heat emergency? The Guardian; The Guardian. https://www.theguardian.com/cities/2019/nov/21/re-greening-can-louisville-plant-its-way-out-of-a-heat-emergency 
• Aruni Bhatnagar on Google Scholar https://scholar.google.ca/citations?user=riRJqrYAAAAJ&hl=en
• University of Louisville faculty bio https://louisville.edu/medicine/departments/medicine/divisions/environmental-medicine/faculty/bhatnagar-aruni

For more research and tips please check out my book and workbook  Take Back Your  Outside Mindset: Live Longer, Stress Less, and Control Your Chronic Illness.

Will you please tell us a little more about you and how you became the  pioneer of  environmental cardiology? 

2:47  The true causes of heart  disease: Environmental  Cardiology

• As a junior investigator studying the electrical activity of the heart in cardiovascular function anddisease
• I came to understand that  we really have not found that the  true causes of the  effects of heart disease. Most people believe that heart disease is caused by malfunction the heart, changes in electrical activity, blocked blood  vessels, or high blood pressure.
• These are the net effects of  a larger set of wider causes that  are mostly external  to us  
• These changes could be related to things that elevate your blood pressure, change your cholesterol.
• So we come to things like diet and exercise and so on that are well   understood
• But I think there are some things that are equally important beyond that such as exposure to air pollution, living environments,  neighborhood conditions.  All  of these  make a difference to our health  and in particular our risk  of heart disease.
• Since these conditions are generally recognized as environmentalconditions,  I think  studying these in order to understand  the origin and the nature of heart disease is what we would call environmental cardiology.

You wrote the textbook on Environmental Cardiology: Pollution and Heart Disease,  and a beautiful research paper titled “Environmental Determinants of Cardiovascular Disease.” (2017) Could you please talk to us about short term exposure to air and noise pollution. Could we start with air pollution please, specifically traffic emissions? What are some of the specific compounds and what can they do to the body in the short term.

4:12  Levels of air pollution don’t have  to  be very  high

• When I started in this field in the  90s, there was a little bit of disbelief that  breathing polluted air could increase the risk of heart disease
• They thought that not exercising for decades was how you got heart attacks
• But the data started to emerge from several studies showing that those people who live in more polluted areas die earlier (the  life expectancy of people was  lower in areas of high pollution).
• This level of air pollution does not have to be very high
• These are levels of pollution that we see around us in  the United States

5:45 Even short term exposure to air pollution can injure heart tissue

• The data started to show that episodic (short term) exposure to air pollution can injure heart tissue (cardiovascular tissue). This can:
  • Can alter the blood pressure
  • Change the electrical activity of the heart
  • Can induce inflammation
  • Can cause damage to the lining of the blood vessels
• We did a study in Utah with a soccer team (6:15) to show this. We found that when there was high  levels of air pollution, there was vascular (blood vessel)  
• All this points to the fact that  there  is a strong tie between air pollution and heart health.
• 80% of the people that die from air pollution, die from heart   

7:00 When there is a spike in air pollution, there is a spike in heart attacks within 6 hours

• Stationary and mobile sources, man made and by wildfire. We had weeks and  weeks of wildfire this summer. It started in the west coast and came  to the  east  Those days can actually trigger cardiovascular  events such as  heart attack.
• There is data showing that (7:47) whenever you have a spike in air pollution there is a spike in heart attacks within 6
• So there is a direct temporal link between air pollution and heart

8:12 Traffic is the Biggest  Source of Air Pollution

• The biggest source of air pollution is traffic relentlessly spewing out pollution into our
• Freeways or highways run through the  middle of neighborhoods, and  people that live next to these have a higher levels of vascular dysfunction and higher risk of heart disease. There are a variety of different effects of living next to  major roadways.

9: 30 Constant noise even at low levels and for brief exposures can  affect heart  function.

• We are trying now to disentangle the impact  of noise from air pollution. Others have shown  that constant noise even at  low levels can  affect heart function.
• Constant noise is shown to increase the risk of diabetes, heart disease.
• Even brief exposure to noise levels can trigger heart events
• The field is looking in particular at “near road environments” to disentangle the effects of air and noise pollution on the  10:07

10:32 Fresh Traffic Emissions Most Harmful Direct

• Fresh traffic emissions are called ultrafine particles or PM 2.5 (and even some  gases that have not coalesced (formed)).
• When you move away further from the traffic you have  fine particles (PM 5) and then course particles (PM10)
• It is believed that fresh emissions are the most harmful
• So when you are close to these roadways (50 to 100 meters) you are likely to be exposed to these particles that are  more likely to be more toxic
•  

12:28 Personal  Question: Knowing  all  this how do you avoid traffic emissions?

• I live on 4 acres of forest..but it is hard for all of us to avoid.
• But we believe this is important
• There islegislation that loosened the  tail pipe emission standards, but I think we are going to get tighter standards back. Advocate for electric cars and so 
• Even then, we live with this. What we were trying to think  of is – what can we  do as  a neighborhood?

13:13 Installing Greeness in our neighborhood to limit our  exposure to air pollutiomn

• That is when we came up with the idea that maybe we can install greenness in our community might help
• The idea is that greater greenness around us could  shield us  from both noise and  air pollution.
• So that  is  one of  the ways that we thought of as  limiting our exposure to air pollution. (13:39)
• Heart disease is the number one cause of death.
• Whatever we are trying stents, statins, then why are we still having heart disease. So maybe we have to consider something more fundamental   like linking healthy hearts to greenness. 
• Nothing is really working, so we have to look for  some fresh ideas that might help.
• So we came upwith this idea that maybe greenness could decrease the risk of heart 
• Yes when you are trained in laboratory chemistry it is very much of a stretch to do something like this.

16:30 Even last year heart disease killed  more people than  COVID.

• I think we should be disparate about trying to lower the risk of heart disease.
• Even last year heart disease killed more people than 
• We accept that as a way of life,  but that is not what we should be accepting.

16:52 There  have been  some very good studies in Canada, US, and Europe showing that people that  live in green areas live longer

• Studies show that these people are healthier, happier, they are less anxious,  have lower  risk  of disease and in particular heart  disease, and lower risk of cardiovascular mortality.
• How do we prove this even  further?

18:10 We do greenness as a clinical trail

• In a clinical  trial  you have a  number of  people, you  don’t give them the drug and the other  half you do give them the   
• And you say, what’s the difference in the people that got the drug? Are they any better?
• So we went to our community and said we want to do this trial in  which one part of the community (18:20) we are going to  plant  trees, and in the other  part of the community we would not (that would be our control area).
• Where we plant the trees would be a target area.
• We want to compare after five years of planting the trees, what  would happen  and what differences would there be?
• So we went to the community, we recruited about a thousand people (18:54) and we measured their cardiovascular disease risk

19:08 We are planting 10-30 foot trees

• If you suddenly plant small trees, it would take several  decades for  these trees to  grow, to be  large enough to  make a difference.
• So I don’t  think we have that  much time, so what we are in the process of  doing is (19:21) planting large  trees – 10 to 30 foot trees  in  a small area.
• So we want to intensively green this area to see what difference it would make.
• In particular we wanted to green  the area  around the freeway which runs right through the community
• So on both sides of the freeway we plant 3 layers of greenness (19:56)
• The smallest trees in the front of the road, successively  increasing to very large trees at the back (at least 30 feet high)
• So then see whether or  not there is a decrease in the emissions from  the road to the neighborhood.
• And more importantly, would this improve the health of the community.

Dr. Bhatnagar you have  such  a technical background in biochemistry and now you  have made this  leap  to support your community.  You must really love Louisville and want  to make it  healthy  again.

20:46  Yes we have lived here for 20 years,  and we  think that if  we are  going to solve problems  on a wider  scale of the world, like a global impact then we should start at home.

• Because I have lived here for so long it is possible to do these things.
• This is s very difficult project to do as you might understand
• It has to do with people’s lives, their property, their neighborhood – you  know you are changing  all  of that, so you need to have the civic authorities, the community   leaders,  the  clinical  community  —   all working together. (21:29)

• You can only do this in a small  city like ours, if you go  to Chicago  or New  York not as easy,  a very small  city will not have the resources, so Louisville  is a city that we can serious work  on  an urban landscape.

22:04 Greeness effects energy costs, community interactions, physical activity

• For instance, greenness could lower your energy costs
• So if you put lots of trees around people’s houses, air  cooling cost decreases (22:14) affecting people’s income and the amount  of money  that they can save. 
• Trees can also change storm water run off
• Trees can change your anxiety and depression levels (we are measuring these)
• Trees can affect social  So  if it is green and pleasant  outside,  people will want to spend time  outside. And when  you are outside you tend   to  interact with your neighbors and  have a greater sense  of community and  a greater  sense  of place (22:51).So we want  to know the effects of greenness on community interactions.
• Maybe time outside will entice people to be more physically active and help their cardiovascular    All this as a  matter of routine  not as a scheduled gym  workout. 
• So all of these things we need to monitor to gauge what the impact of greenness can improve.  

23:59 Vit D is critical  in  regulating your immune responses, avoiding depression, lowering risk of heart  disease  

• When we  get outside we undergo photosynthesis just like plants(23:59) 
• We have to go through photosynthesis to create vitamin D
• There is very little Vit D in  other  food sources,  we  need sunlight for this so we  can make our  own  (24:27)
• Vit D is critical in regulating your immune responses (24:36), your bone growth,  your cardiovascular health, your blood  pressure, and your mood. 
• The thing is we can only make Vit D through the UV that comes through our skin, and that is the reason  that people in  northern  latitudes have light skin and people in southern   latitudes have darker skin. 
• So it is critical to be outside to get a  level  of Vit D
• In northern latitudes from November to  March it is difficult to get  any  Vit D
• The good news is that you can get Vit D in summer to get you through the winter months. There was a study that Swedish women who  spent  their summers in  Italy lived longer (26:21)
• You can store a lot of vit D because it is stored in your liver.
• Vit supplements, lights, Seasonal Effective disorder (SAD) – depression
• Vit D is particularly relevant to  heart disease because we know if you  are depressed you have a higher risk  of  heart disease. This risk may be even more than the risk  of smoking. (27:18)
• There is a  strong link between  depression and  heart disease. (27:26)  and more heart  disease in winter compared to summer in northern latitudes. May be  due to  lack of Vit D or depression.
• We have known for a long  time about the power of sunlight in  myths and legends,  but there   is an actual demonstrated   link  between sunlight and health.
• Even independent of Vit D, sunlight  can  lower blood  pressure (28:09)
• Strengthens your immunity (used for tuberculosis) and helps us to be more resilient to  any pathogen invasions
• We know that people have lower levels of cholesterol in the  summer than in the winter (28:06)

29:46 Sleep  and Sunlight  

• Not only does Vit D regulate your immune system, lower your blood pressure, it resets the biological  
• So there is a centre in the brain called the superchiasmic nucleus, and this nucleus can regulate what is called our master clock
• It gets entrained and reset by the daily input of light (30:16)
• So if you are exposed to sunlight at appropriate times, that improves your sleep quality
• Particularly early in the day if you see direct sunlight within the first 5 hours of waking up  in  bright light, you have  much easier time of falling  asleep at night. (30:39)
• Because then your melatonin levels are degraded
• And so sunlight is a very  important cue for regulating biological rhythms and for regulating sleep

31:03 People who live in more polluted areas have poorer sleep  quality.  

• Sleep has the  same magnitude of the effect on the  heart as physical activity and a good diet
• Good sleep is absolutely critical for heart health
• We know that people who get less than 6 hoursand more than  8 hours have a greater risk of CV 
• So there is a very narrow window say around 7-8 hours that is optimal  (31:46)
• It is not only the time,but the  quality of the sleep – broken  sleep, sleep apnea,  have long term  health effects and in particular CV 
• People who live in more polluted areas have poorer sleep  (32:15)

• So air pollution creates poor sleep  quality which can lead to heart disease.

• These are all interlinked. In our area we have UPS planes running from 1-3 am so there  are some places that have perturbed sleep and that  has  dire health consequences. 

33:09 The major risks to our heart are imparted by the environment

• So we have been telling people, and as physicians saying, that the reason you have  heart disease is that you are  fat, and  you smoke, ear bad food, you are lazy and that  is why you have had a heart attack.
• Now we know that there are some things even beyond our control,(34:04) that can  be very strong risk  factors for heart 
• Every physician tells their patient to exercise  more
• But we create for example, cities where it is impossible to go anywhere to walk.
• And then we say well it’s your  fault that you  don’t get exercise
• We know that people who live in more crowded areas like London or Toronto, they are running around going to subways  -they are out there active – so  those people tend to be  healthier than (35:02) rural  people who have to drive everywhere.  And can’t walk to get anywhere.
• Same people with people in the American south where roads are only accessible by cars.
• So you tell people to be physically active and then you do everything possible to prevent them  from being physically   (35:28)
• Then we are all aghast at how obesity is increasing
• Same thing with food..if  you go to a  grocery store and the isles on the inside of the store, 80% of that food has no nutritional value.
• The real food is actually on the outside.
• Less than 10% of the food at the grocery  store is actually food.
• We take away all the choices and sort of bias the behavior toward bad food, and then  we blame people about not making the  right choices. (36:02)

36:37 Need to Act Collectively 

• Too difficult to correct all this on an individual level,  so  we need to act  together  about neighborhoods, sound, noise, light, and air pollution. (36:56) and greenness.
• We need to be more aware that this is a serious public health issue. That we must have green neighborhoods where people feel  comfortable walking outside  without high levels of noise and air pollution  . (37:18)
• This is not  something people have an  individual  choice about – this is a  community looking at what sort of a life we want to live and what we  need to do to create that life. (37:39)

38:03  What you are pulling  together is incredible. What in your life and background has  given  you the ability to think and work this way?

• I am not a religious person, but in India, I was brought up  by catholics and missionaries. 
• The basic thingwe learned primarily is that we need to care for people around  
• To care for total strangers and to care  for the world around you is  an important 
• So if we are going to do research,  we wanted to  see as a group, we wanted to  do research that was relevant to the world and to  our lives (39:11)

39:46 Most Exciting About the  Green Heart Project

• The difference it will make to people’s lives
• This is a low to middle income neighborhood, there has been very little  attention to them at all
• This area has abandoned lots, has homeless people,  there is crime
• So if we can directly, or  indirectly make a little  difference there, to improve the quality of life of these  people that would be a  major achievement. 
• And to be able to document that: what changed,  what made a difference
• The most exciting thing would be  if we could create a blue print, or as some people say a green print (41:27) that we can  then share with the rest of the  world and say this is how we can  create healthy neighborhoods and this is how can create  cities in the future.  

I don’t think that there is any  other project like this?

• No there is not but I can not take all the credit. There are about 50 people working on this
• We have support for the clinical trial from the national institutes of health (42:19).
• They are excited, but not excited about buying the trees.
• So we had to turn to somebody else,  so we  turned to the  nature conservancy.  They have been  very generous.(42:35) They did  an international fund raising  for our  project and they  raised over 8 million dollars just to plant  the trees.
• The trees come in from all over the country  by truck.
• Then we have air pollution  experts from Washington University
• We have people from New York looking at air pollution dynamics
• We have people from California at the Hyphae Design Lab they are designing our  greenness  interventions   (43:27)
• Community activists

44:12 One piece of advice for our listeners?

• The single best thing you can do  for your physical  health is physical activity, and equally important is good sleep.
• It is not difficult to do. If you make an attempt to develop sleeping hygiene and good restful sleep, you can brave a lot of things in the 
• So the single most important determinant of health is to sleep well.
• But it is not that simple because in order to sleep well you need to (45:05)exposed to enough sunlight, have good nutrition, be physically active so you get  tired by the end of the day,
• So sleep is the thing that reflects all the day’s activities: physical activity, air and noise  pollution, how much sunlight you have been exposed to..
• All these things are integrated and lead to good sleep (45:41)

Anything else you would like to mention?

As you know we  have  the University of Louisville Christina Lee Brown Envirome Institute https://enviromeinstitute.com/

• Here we  want to show that science is important and  critical to our everyday lives, not  something locked in the labs  (46:47)
• That science  has social relevance
• We cannot move forward without people who figure out for us how to live better.

Thank you Dr Bhatnagar, please keep going with your work  and your perspective on science. 

• Thank you Verla for your work and  your book  and their important messages to  get out into green spaces..
• Sunlight, green spaces, clean air,  less  noise, good sleep can only accrue if you get outside.

Is there one thing from all  that we  have discussed today, that our  listeners can do to help protect their hearts?

Thank you for showing us how important it is to understand how dramatically the heart is affected by our environments. And  for sharing easy natural ways for us to help our hearts.

So listeners remember, as Dr Bhatnagar points out plan your way around air and noise pollution  in  your day if you  can. Build in patches of green  space and sunlight  to protect your heart. As Dr Bhatnagar says when you protect and plant trees you are helping your heart  and your community  —  and probably doing you love. Until next time.