WEBVTT 00:00:00.000 --> 00:00:02.399 Okay, Chelsea, instead of doing somewhat doom 00:00:02.399 --> 00:00:05.059 and gloom, I actually have a good idea. I'm going 00:00:05.059 --> 00:00:07.940 to do a follow -up on a way long ago episode. 00:00:08.460 --> 00:00:10.759 It's not really a follow -up. It's just following 00:00:10.759 --> 00:00:13.240 in the trajectory of that episode. We're going 00:00:13.240 --> 00:00:17.920 to talk about that negative impact of lawns in 00:00:17.920 --> 00:00:21.160 a weird roundabout way. And an article that actually 00:00:21.160 --> 00:00:25.320 came out on January 21st, 2026 from UC Davis 00:00:25.320 --> 00:00:28.379 Health, written by Lisa Howard, article title, 00:00:28.829 --> 00:00:31.489 trees, not grass and other greenery associated 00:00:31.489 --> 00:00:34.990 with lower heart disease risk in cities. Really? 00:00:35.270 --> 00:00:38.829 New research analyzing 350 million street view 00:00:38.829 --> 00:00:42.729 images finds urban tree canopies may reduce cardiovascular 00:00:42.729 --> 00:00:46.549 disease while grassy areas may increase it. Multi 00:00:46.549 --> 00:00:48.850 -institutional study led by the University of 00:00:48.850 --> 00:00:51.289 California, Davis finds that living in urban 00:00:51.289 --> 00:00:53.070 areas with a higher percentage of visible trees 00:00:53.070 --> 00:00:55.270 associated with a 4 % decrease in cardiovascular 00:00:55.270 --> 00:00:58.200 disease. By comparison, living in an urban urban 00:00:58.200 --> 00:01:00.479 area with a higher percentage of grass was associated 00:01:00.479 --> 00:01:02.920 with a 6 % increase in cardiovascular disease. 00:01:03.280 --> 00:01:05.579 Likewise, a higher rate of other types of green 00:01:05.579 --> 00:01:07.819 space like bushes or shrubs were associated with 00:01:07.819 --> 00:01:10.939 a 3 % increase in cardiovascular disease. Quote, 00:01:11.019 --> 00:01:13.180 our findings suggest public health interventions 00:01:13.180 --> 00:01:16.140 should prioritize the preservation and planting 00:01:16.140 --> 00:01:19.040 of tree canopies in neighborhoods. End quote, 00:01:19.079 --> 00:01:21.939 said Peter James. First author of the study, 00:01:22.019 --> 00:01:24.879 James is an associate professor at UC Davis Department 00:01:24.879 --> 00:01:27.200 of Public Health Sciences and director of the 00:01:27.340 --> 00:01:29.239 Center for Occupational and Environmental Health. 00:01:29.400 --> 00:01:31.640 Quote, urban forestry initiatives and policies 00:01:31.640 --> 00:01:33.900 that protect mature trees are likely to yield 00:01:33.900 --> 00:01:36.799 greater cardiovascular health benefits and compared 00:01:36.799 --> 00:01:39.379 to investments in grass planting. End quote, 00:01:39.480 --> 00:01:42.640 James said. In 2023, more than 900 ,000 people 00:01:42.640 --> 00:01:45.060 died from cardiovascular disease in the U .S. 00:01:45.099 --> 00:01:47.920 That's the equivalent of one in every three deaths, 00:01:47.959 --> 00:01:49.980 according to the Center for Disease Control and 00:01:49.980 --> 00:01:52.159 Prevention. Oh man, from a time you could trust 00:01:52.159 --> 00:01:54.640 them. Cardiovascular diseases are serious conditions 00:01:54.640 --> 00:01:56.840 that affect the heart and blood vessels. This 00:01:56.840 --> 00:01:58.939 includes problems with the heart, such as arrhythmia, 00:01:59.040 --> 00:02:01.519 heart valve disease, and heart failure. And problems 00:02:01.519 --> 00:02:03.540 with blood vessels like blood clots, including 00:02:03.540 --> 00:02:06.879 strokes, and peripheral artery disease. Previous 00:02:06.879 --> 00:02:09.520 research using satellite imagery has shown that 00:02:09.520 --> 00:02:11.699 urban green spaces can be beneficial to public 00:02:11.699 --> 00:02:14.259 health, but satellite imagery can classify a 00:02:14.259 --> 00:02:16.960 wide range of vegetation as green space. Quote, 00:02:17.000 --> 00:02:19.340 satellite imagery has allowed for important new 00:02:19.340 --> 00:02:21.280 understandings about how the landscapes built 00:02:21.280 --> 00:02:24.250 and natural can influence human health. But because 00:02:24.250 --> 00:02:27.389 the view is from above, far, far above, and lumps 00:02:27.389 --> 00:02:29.830 all types of vegetation into one category, it 00:02:29.830 --> 00:02:32.090 can mask differences that may be significant, 00:02:32.370 --> 00:02:34.610 end quote, James explained. James is a prominent 00:02:34.610 --> 00:02:36.729 researcher known for innovative use of street 00:02:36.729 --> 00:02:39.250 -level imagery and satellite imagery in environmental 00:02:39.250 --> 00:02:41.830 health research. Street -level imagery, most 00:02:41.830 --> 00:02:44.030 commonly derived from the platform Google Street 00:02:44.030 --> 00:02:46.750 View, captures neighborhood environments photographed 00:02:46.750 --> 00:02:48.889 from the vantage point of what a pedestrian would 00:02:48.889 --> 00:02:51.270 see and has been increasingly used in public 00:02:51.270 --> 00:02:53.550 health research. The new study was among the 00:02:53.550 --> 00:02:55.590 first to create a street level assessment of 00:02:55.590 --> 00:02:57.889 how trees grasses and other green spaces would 00:02:57.889 --> 00:03:00.050 impact cardiovascular health the researchers 00:03:00.050 --> 00:03:03.169 used deep learning to analyze more than 350 million 00:03:03.169 --> 00:03:05.909 trees street view images to estimate how much 00:03:05.909 --> 00:03:08.189 of each neighborhood was covered by trees grass 00:03:08.189 --> 00:03:11.590 or other green space they then linked those findings 00:03:11.590 --> 00:03:14.310 to nearly 89 000 women in the ongoing nurses 00:03:14.310 --> 00:03:16.870 health study they determined that the type and 00:03:16.870 --> 00:03:19.270 percentage of greenery trees grass or other green 00:03:19.270 --> 00:03:22.310 spaces within about 500 meters of each person 00:03:22.349 --> 00:03:52.159 Interesting. Interesting. such as population 00:03:52.159 --> 00:03:55.460 density, census region, air pollution, and neighborhood 00:03:55.460 --> 00:03:58.439 socioeconomic status. The researchers were surprised 00:03:58.439 --> 00:04:00.620 by the potentially harmful association with grass 00:04:00.620 --> 00:04:03.240 and other green spaces, but the surprise findings 00:04:03.240 --> 00:04:06.039 highlighted the importance of disaggregated green 00:04:06.039 --> 00:04:07.939 space data to better understand cardiovascular 00:04:07.939 --> 00:04:10.800 effects. The authors suggest that there may be 00:04:10.800 --> 00:04:12.879 multiple reasons for the unexpected negative 00:04:12.879 --> 00:04:15.340 association, including an increased use of pesticides, 00:04:15.780 --> 00:04:18.639 air quality impacted from mowing, lower cooling 00:04:18.639 --> 00:04:21.040 capacity compared to trees, and low capacity 00:04:21.040 --> 00:04:23.699 to filter noise and air pollution additional 00:04:23.699 --> 00:04:26.199 additional research may help identify the unique 00:04:26.199 --> 00:04:29.019 environmental factors that can adversely impact 00:04:29.019 --> 00:04:31.959 cardiovascular risk the study had several limitations 00:04:31.959 --> 00:04:34.399 first the cohort is all female and primarily 00:04:34.399 --> 00:04:37.800 white which limits generalizability due to the 00:04:37.800 --> 00:04:40.420 relatively homogenous racial and socioeconomic 00:04:40.420 --> 00:04:43.459 backgrounds of participants also researchers 00:04:43.459 --> 00:04:46.519 use the nurses residential addresses which don't 00:04:46.519 --> 00:04:48.649 capture how they spent their time for example, 00:04:48.649 --> 00:04:50.790 at work, or how they interacted with other green 00:04:50.790 --> 00:04:53.350 spaces, when street view images only represent 00:04:53.350 --> 00:04:55.629 a snapshot in time and cannot see private green 00:04:55.629 --> 00:04:57.930 spaces that may influence health, such as the 00:04:57.930 --> 00:04:59.910 backyard gardens. Despite these limitations, 00:05:00.269 --> 00:05:03.089 the findings offer significant insights. Quote, 00:05:03.129 --> 00:05:05.370 the research opens a promising new avenue improving 00:05:05.370 --> 00:05:07.689 cardiovascular health through community -level 00:05:07.689 --> 00:05:09.829 environmental changes rather than relying solely 00:05:09.829 --> 00:05:12.430 on individual lifestyle choices. End quote. Said 00:05:12.430 --> 00:05:15.899 Erica Rimm, co -author of the study. Rim is professor 00:05:15.899 --> 00:05:18.579 of medicine at Harvard Medical School and of 00:05:18.579 --> 00:05:21.339 epidemiology and nutrition at the Harvard T .H. 00:05:21.339 --> 00:05:23.639 Chan School of Public Health. Quote, heart disease 00:05:23.639 --> 00:05:26.079 has such an enormous impact on the Western world 00:05:26.079 --> 00:05:28.120 that even moving the needle slightly towards 00:05:28.120 --> 00:05:31.199 earlier prevention can make meaningful difference. 00:05:31.420 --> 00:05:33.879 End quote, Rim said. That's the end of the article. 00:05:34.180 --> 00:05:35.980 Chelsea, what do you think? Does that mean that 00:05:35.980 --> 00:05:38.959 doctors should be like when you can tell that 00:05:38.959 --> 00:05:41.720 there's some cardiovascular? I'm not a doctor, 00:05:41.759 --> 00:05:45.209 so don't rate my eloquence of putting. this do 00:05:45.209 --> 00:05:48.149 you live near trees well i would they might be 00:05:48.149 --> 00:05:49.970 saying like what do you have planted in your 00:05:49.970 --> 00:05:52.449 yard or what's your community look like yeah 00:05:52.449 --> 00:05:55.069 if not we're gonna and they might even say we're 00:05:55.069 --> 00:05:56.949 gonna have to be pulling this out you're at risk 00:05:56.949 --> 00:05:59.970 of heart attack we need you to pull out all that 00:05:59.970 --> 00:06:03.819 grass And plant some trees and have them grow 00:06:03.819 --> 00:06:06.740 real quick. It's super interesting. It really 00:06:06.740 --> 00:06:08.819 is. And like, really think about that. Like a 00:06:08.819 --> 00:06:12.500 4 % decrease versus a 6 % increase. Yeah. So 00:06:12.500 --> 00:06:15.740 we're talking about 900 ,000 people a year that 00:06:15.740 --> 00:06:19.399 this impacts. That's a 10 % swing or 90 ,000 00:06:19.399 --> 00:06:23.139 people. Yeah. It seems like a lot and doesn't 00:06:23.139 --> 00:06:26.379 even make sense to me. But that's a crazy correlation. 00:06:26.480 --> 00:06:29.839 Like grass versus trees. Thank goodness I have 00:06:29.839 --> 00:06:32.410 some trees. outside of my house. Yeah, but they 00:06:32.410 --> 00:06:34.629 did point out like there's some interesting parts 00:06:34.629 --> 00:06:36.769 of it. I do also think it'd be interesting to 00:06:36.769 --> 00:06:38.430 compare that to somebody who lives with like 00:06:38.430 --> 00:06:41.129 a lack of green, whether or not that has a difference 00:06:41.129 --> 00:06:43.610 too. But we've seen it too with like golf courses 00:06:43.610 --> 00:06:46.110 impacting the local water supply when it's groundwater 00:06:46.110 --> 00:06:48.449 that you're getting. Yeah. The pesticides, we 00:06:48.449 --> 00:06:50.529 don't really know the full impact on the human 00:06:50.529 --> 00:06:54.029 life that it has. The lawnmowers, they have CO2. 00:06:54.170 --> 00:06:55.990 Maybe there's going to be an impact with batteries 00:06:55.990 --> 00:06:59.069 doing this now, but you're also potentially having 00:06:59.069 --> 00:07:01.350 your own exercise be every other week mowing 00:07:01.350 --> 00:07:04.889 the grass and like they said like stressors include 00:07:04.889 --> 00:07:09.209 noise pollution which trees can block yeah so 00:07:09.209 --> 00:07:11.089 maybe you just have a less stressed lifestyle 00:07:11.089 --> 00:07:13.569 but maybe also this doesn't impact men at all 00:07:13.569 --> 00:07:16.790 and actually it is one of those very gendered 00:07:16.790 --> 00:07:18.889 stereotypes is men are the ones who take care 00:07:18.889 --> 00:07:20.709 of the yard so maybe they're actually getting 00:07:20.709 --> 00:07:23.069 the health benefit of having the yard not looked 00:07:23.069 --> 00:07:25.310 at because it's the women that are in this long 00:07:25.310 --> 00:07:28.920 toodle study so many implications yeah and Hey, 00:07:29.060 --> 00:07:31.120 you guys got 48 hours. Think of more. And email 00:07:31.120 --> 00:07:33.259 these guys. Maybe they'd like that. I don't know. 00:07:33.420 --> 00:07:35.240 Maybe email us. Tell them we sent you. We have 00:07:35.240 --> 00:07:39.360 got no emails. Yeah, we were just talking about 00:07:39.360 --> 00:07:44.959 that. Send us some. Okay. Yeah. Anyhow, bye. 00:07:45.160 --> 00:07:45.300 Bye.