Ginny Robards
Jonathan Burdette, PhD
30
Aging has long been characterized as a loss of the ability to adapt to various forms of stress, which gradually results in loss of function and disease. This is most evident in the muscles and bones, but neuroimaging has revealed that this occurs in the brain as well. Compared to young people, the aging brain is less specialized. As elderly people carry out a task, there is increased activation in areas of the brain that did not used to be involved, possibly as a way to compensate for poorer signal transmission. One intervention that we know helps to protect against this is exercise. No big surprise there. Another, oddly enough, is beetroot juice.
Why?
Beetroot juice is a very rich source of nitrate, which acts as a precursor to nitric oxide. Nitric oxide relaxes the walls of blood vessels, reducing blood pressure and enhancing blood flow. This is one reason beetroot juice has become a popular exercise supplement, because it reduces the workload for your heart, and makes it easier for blood to get to your muscles. There have been some interesting studies supporting nitrate as a performance enhancer. For instance, a recent study found that mice that were fed high doses of nitrate ran 20% faster and 30% further than counterparts that were not given the supplement. Pretty cool.
But beetroot juice can do more than just help you set new PRs. There is reason to believe that the changes in blood flow associated with dietary nitrates may also affect your brain in ways that are not dissimilar to exercise. For example, a randomized controlled trial found that healthy adults who consumed 450 ml of beetroot juice experienced greater cerebral blood flow. They also did better on a test of cognitive performance administered during the trial. But what happens when you combine beetroot juice and exercise? That question brings us to my guest today.
Guest
In this episode of humanOS Radio, I talk to Dr. Jonathan Burdette. Dr. Burdette is a neuroradiologist and researcher at Wake Forest School of Medicine. He uses advanced magnetic resonance imaging techniques to study the brain as a complex and interconnected network. Recently, he and his team designed a clinical trial to investigate whether beetroot juice in combination with an exercise regimen could enhance neuroplasticity and improve brain function. Let’s take a look at what they did.
Study
The researchers recruited 26 elderly subjects (mean age 65.4 years). Each was randomly assigned to one of two conditions:
- Exercise (three 50 minute walking sessions per week) plus Beet-It Sport Shot (beetroot juice with 560 mg of nitrate).
- Exercise (three 50 minute walking sessions per week) plus Placebo (beetroot juice with nitrate reduced to negligible levels).
The researchers used magnetic resonance imaging to analyze function and connectivity in the brain (the degree to which different parts of the brain were active at the same time). So, what did they find?
The exercise plus beetroot group had reduced interconnectivity between the somatomotor cortex and insular cortex.
Why does this matter?
Age-related loss of mobility has been associated with an increase in secondary connections between the somatomotor cortex and other parts of the brain. Young people have less of this compensatory interconnectivity, so their brains perform more efficiently.
The intervention group in this study had brains that more closely resembled that of the scans of younger individuals. This suggests that beetroot juice in combination with physical activity may make more brain networks more similar to younger people, benefits that are greater than exercise by itself.
I’d like to mention a nitric oxide product I have tried recently from Berkeley Life. Instead of taking an actual beetroot shot, you can increase nitric oxide levels by taking pills, which has added convenience (and no sugar). Personally, I have a hard time with the taste of beets, so this has been an easier way for me to boost my nitric oxide levels. (Please note, I have no financial relationship with either Berkeley LIfe or Beet It Sport, there are other beetroot and nitric oxide products on the market, and I have not tried them all, so I can’t say if one product is better than another.)
InTUNE Training
Finally, in this episode, Dr. Burdette and I speak about the importance of mixing in movement throughout your day. The importance of this inspired us to create InTUNE Training, which stands for Integrative and Opportunistic Training.
This program in humanOS.me gives you a new bodyweight workout each day. The volume of activity in each workout is approximately equal to the 7-minute workout, which was popularized a few years back.
While you can do all of the exercises back to back (like a normal workout), InTUNE also encourages you to break up the activity and chip away at the designated reps across the day, recording your reps in the box to the right each time you do complete them. Just aim to have all the work done by day’s end.
To the right is an example of a workout. By the way, if you don’t know what one of the exercises is, click on the [+] box in the upper right-hand corner for a demo of the exercise.
Give it a try today!
For more details on Dr. Burdette’s work, and to learn how you can take advantage of the findings for yourself, check out the interview below!
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Transcript
Jonathan Burdette - 00:05: Of course the aging brain can still change. It's plastic. Exercise has been shown to change actual gray matter volume and white matter volume so structural changes as well as functional changes.
Kendall Kendrick - 00:20: humanOS. Learn. Master. Achieve.
Dan Pardi - 00:29: Dr. Jonathan Burdette welcome to humanOS Radio.
Jonathan Burdette - 00:33: My pleasure to be here.
Dan Pardi - 00:34: If you could give our listeners introduction to who you are, where you work, and the type of research you do.
Jonathan Burdette - 00:40: Okay, I am a neuroradiologist so a brain imaging guy at Wake Forest School of Medicine in Winston-Salem, North Carolina. Fifty percent of my life is clinical so all last weekend I was reading CT scans and MRI scans of people's brains and spines and 50% of my life as part of the Laboratory for Complex Brain Networks that I co-founded with Paul Laurienti and where we research the brain from an imaging standpoint using brain networks. I would say over the last decade there's been a big shift from traditional fMRI to a network science based methods but looking at the brain more as a collection of connected nodes and looking at relationships between areas of the brain rather than just this area of the brain does this or this area of the brain does that.
Dan Pardi - 01:27: Generally, aside from looking at network patterns are there certain topics that you're interested in exploring?
Jonathan Burdette - 01:34: Yeah, our lab is pretty focused on healthy aging or the aging brain and we work closely with the undergraduate campus at Wake Forest University, the Translational Science Center there whose mission is to come up with practical applications to translate health research into practical things for older adults basically, help them foster independence without taking medications and things like that. We work closely with them so this whole healthy aging and investigate exercise effects, food effects, and things like that. We've also worked in a big project in migrant farmers and the effects of pesticides in the brain because there's a large migrant farmer population here in North Carolina. We've also done things like the effects of music on the brain, which also affects old people, worked in caffeine, thinks like that. Mostly healthy aging now and that's a lot of what our lab does.
Dan Pardi - 02:26: Tell us about your most recent study looking at beetroot juice of all things.
Jonathan Burdette - 02:30: Of all things.
Dan Pardi - 02:31: Of all things so why beetroot juice and what were you specifically exploring?
Jonathan Burdette - 02:36: We need our nitrogen species for optimal blood flow. Researchers know that nitric oxide dilates blood vessels, decreases blood pressure, increases blood flow especially in a hypoxic conditions. Well, vegetables for example like beets are loaded with nitrate and so if you eat your beets you will get a boost in your nitrate, which will then be taken up by your salivary glands and converted to nitrite, which will then travel around looking for hypoxic areas and be converted to nitric oxide and you'll increase your blood flow. That has been shown over, and over again if you're diabetic with poor circulation you'll increase your circulation if you increase the amount of nitrate, in this case nutritionally. It's been shown in sports and athletes, the London Olympics the beetroot juice Olympics. People are taking beetroot juice shots all the time to increase blood flow. My daughter runs cross country, she takes a beetroot shot an hour before she races and feels like it helps her. It may just be mental but actually it probably does help her.
03:33: We knew that and we had done a study that's showing acutely that if you scan someone and get their blood flow to their brain do a beetroot juice shot, scan them again, you will have acute changes in blood flow to your brain. We show this in elderly people to the deep white matter in the frontal lobes.
03:49: We had some preliminary data, beetroot juice does what it's supposed to do. It increases blood flow probably to the brain. We know as you age your capacity of your blood vessels to your brain decreases and you get chronic ischemic change, which is what you get. We knew there were some acute changes so this might be helpful. We also know that exercise can lead to neuroplasticity in the aging brain and that's been shown in lots of studies. We know that beetroot juice helps exercise and so we thought well, maybe if there's some synergistic effects between the beet juice and the exercise on the aging brain. That's what we did. We tested that and looked specifically at somatomotor regions, communities based on other previous work from around here and found some interesting results. It did have synergistic effects on the brain communities. That's exciting.
Dan Pardi - 04:39: For those that are unfamiliar with the term neuroplasticity, give a primer on that.
Jonathan Burdette - 04:42: The brain changing structure function due to a certain stimuli, a certain activities is not a super deep thought but it was thought that the aging brain really didn't change that much. It wasn't that dynamic and of course that's been blown out of the water that of course the aging brain can still change. It's plastic. Exercise has been shown to change actual gray matter volume and white matter volume so structural changes as well as functional changes just basically changes in structure and function due to certain activities and or certain inputs.
Dan Pardi - 05:13: How unique are beets? How different are they than other vegetables in the amount of nitrates they contain? Is it a lot more or it just tends to be one of the higher sources that we have in nature?
Jonathan Burdette - 05:23: That's a great question. I'm not a nutrition expert. Actually, Gary Miller is the nutrition expert in this study. However, it is a very good question because we go online you will see that beets are not the highest in nitrates. If you eat arugula greens, it's actually even higher. Beets are very high in nitrate but there're all your green leafy vegetables are also very high. You've kale, spinach, these sorts of things. I think it's easy to make beet juice rather than a kale juice or arugula juice but all of those vegetables are loaded with nitrogen species as well as antioxidants, vitamins and magnesium and iron, also folate, B vitamins. Again, eat your vegetables but I don't actually have an answer to why beetroot juice rather than other high nitrogen species except that you can make it.
Dan Pardi - 06:14: Maybe it's just more palatable for people than arugula shot. By the way, I've tried beetroot shots before exercise and I've noticed that and one of the more interesting things coming back to sleep that I've heard recently is that when we have less sleep than we need so you miss a couple of hours over the night you have a decrease in the substance called BH4 so we don't need to really go into that but the result of it is you have decreased nitric oxide and you then see an increased activity of these sleep promoting cells in the brain. What I've experimented with and what I've also read in researching for this podcast, I went online and I looked at the beet product used in your study. One of the first comments from somebody was talking about how they had improved alertness and they weren't expecting that.
Jonathan Burdette - 06:54: It probably is related to what your sleep work.
Dan Pardi - 06:56: Yeah, it really suggests that if you want to have good alertness and who doesn't I mean how many people drink caffeine in the world? Particularly if you missed out on your ideal night of sleep, having nitrite containing food in the morning either through the form of a juice or a salad, something like that can potentially go a long way in helping you feel a lot better during the day. Not only are you trying to necessarily amp up the alerting effects of blocking adenosine through caffeine but you actually might be reducing the pressure for sleep by affecting these sleep promoting cells. Totally speculative but there is an interesting mechanism and I've been playing with it a little bit and I feel like I do perform better when I have veggies in the morning whether I got good sleep or didn't.
Jonathan Burdette - 07:35: Interesting.
Dan Pardi - 07:35: What was this intervention like? How many groups did you have or what were you testing?
Jonathan Burdette - 07:39: Yeah but that same company that does the Beet It shots has a placebo that looks just like the other one but does not have the nitrogen in it. That's why they are a very convenient group to use. Half the people of the 26 people, half would take a beetroot shot one hour before exercise. This was an aerobic exercise intervention on a treadmill. It was a six-week intervention that they would come in three times a week so six times three, 18 treadmill interventions if you will and they would take their beetroot shot one hour before the exercise. On the other days, they actually drank beetroot shot about the same time every single day, seven days a week they did a beetroot shot. But, three of those days they actually had an exercise intervention and this was performed on elderly people though I'm getting very close to their age, greater than or equal to 55 years old, sedentary people, which can be defined I think it's less than 60 minutes of moderate exercise in a week.
08:39: We actually chose people with some mild hypertension, blood pressure 130 to 160 because we thought the beetroot juice might have a bigger effect on these people quite frankly and this is preliminary work. That's the group and half of them took Beet It and half of them took a placebo. Actually the Beet It shot itself has about 560 milligrams I think of nitrate, which is handful of beets, basically, maybe three beets. So three sessions a week and they would come in and be monitored.
09:08: Experts on physiology of such things are monitoring for MET capacities because that was another question. Do they actually improve more if you took the beet shot? They almost did statistically, it was close. Definitely had a trend toward better exercise performance, which has been shown already in athletes. That's the study and I being an imager was very interested in what the brains looked like so all these people were scanned before the study started within a couple of days and then after the study was over not on an exercise day within a couple of days after the study was over. We just did comparing pre and post. That's where we found our findings.
Dan Pardi - 09:42: Five days a week or was it seven days a week they were taking the beetroot shot?
Jonathan Burdette - 09:46: Everyday they took a beet shot.
Dan Pardi - 09:47: Okay, three days a week they exercised.
Jonathan Burdette - 09:49: Correct.
Dan Pardi - 09:49: They did 50 minutes of walking essentially in this sedentary population that was mildly hypertensive and although there was a trend towards improvement in exercise performance perhaps you would have seen them if the study went longer or-
Jonathan Burdette - 10:02: More people.
Dan Pardi - 10:03: Yeah, more people, exactly. Okay, tell us a little bit more about the connectivity. What was found there?
Jonathan Burdette - 10:08: We were very interested in this group of the somatomotor regions, the community, using what people call modularity analysis. If you have a certain module, you would say that these areas are talking to each other more than to other areas of the brain. That would be considered a module and so we're interested in this case the somatomotor regions because of some work done here by Christina Hugenschmidt where if you take elderly people and characterize their physical fitness if you will doing what's called an SPPB battery, which is a very simple test actually. It has a few components one of which is sit in a chair without using your hands stand up and sit down five times and you can time someone doing that. That's not a trivial thing to do and then another thing is a balance where you put one foot in front of the other and then keep doing that. One's a walk.
10:56: You can score people. Older people who scored very well in this, brains had very intact somatomotor modules, cortex if you will and had very few connections from that cortex to the insula. As the scores got worse and worse the worst performing people had a lack of intactness, very inconsistent somatomotor cortex and tons of connections between that and the insula.
11:21: Young people in that same study had very intact somatomotor and very few connections. We were wondering pre, post in our study what would this module look like? What would their connections to the insular cortex look like? Very long story short, the people who did use the beetroot shot changed over the time and their brains at the end looked a lot like the younger people and with very intact somatomotor cortex, very few connections to the insula. The insula known to process all sorts of things, interactions of cognitive and sensory, and also autonomic and all sorts of stuff as opposed to people who do not get the beet shot who had a lack of a cohesive somatomotor cortex module and lots of connections to the insula.
12:06: That's poetry at this point but you got to hypothesize that perhaps they needed those connections with the insula. They're trying to monitor the world in a certain way in order to do their motor. That's the way they get through the world, whereas, these other people actually got better. Again, just the people who got the beetroot shot looked more like the younger people and I'm not going to sit here and say, "You'll be like a young brain if you do that," but there's no question that in these findings looked more like young people. Analysis showed you can change in a very short amount of time.
Dan Pardi - 12:32: That's what's incredible to me.
Jonathan Burdette - 12:33: That's amazing, yeah.
Dan Pardi - 12:34: Yeah, this short trial with-
Jonathan Burdette - 12:36: Pretty mundane intervention by the way.
Dan Pardi - 12:38: Pretty mundane that just means that if you try a little bit, you're going to make some meaningful changes to the way your body is working and this is another example of that which is exciting.
Jonathan Burdette - 12:47: You're absolutely correct and take that another step further especially as you age you don't want to hear that you have to do high intensity training. It's very [inaudible 00:12:54] to do that in fact you can argue it's nearly impossible as you get in your 60s and 70s to doing anything hard enough to get your heart rate up.
13:01: One of my colleagues, Jack Rejeski will preach that quite frankly all you got to do is tell old people to get up and move. Just get up. Just get up and move and be ambulatory. Don't just sit there and my garage door opener is broken right now and I haven't fixed it. Because it forces me to get out of the car, go over, make my garage open, get back into the car. Yeah, it's a pain but I'm not fixing it because it forces me to do something else.
13:27: As you age, just keeping that in mind as silly as Fitbit is on some levels it's actually quite good in that it's a reminder you need to keep moving. I would even argue I know Jack Rejeski'd argue that needs to be spread out throughout the day. If you're sitting all day at a desk, if you're a young millennial who's working their tail off at Ernst & Young all day just sitting there, sitting there and you go home and you pound your Pure Barre or your high intensity swimming or something, yeah, that's good. It's probably better that if you've been moving all day. Use a standing desk. Make sure you just keep moving and I think many researchers in this area would argue that is the case. It's doable. That's easy. You can tell someone to move. That's a lot easier than saying get a gym membership and join a class.
Dan Pardi - 14:11: I invented something called in tune training.
Jonathan Burdette - 14:13: Uh-hu.
Dan Pardi - 14:14: It stands for integrative and opportunistic training. In modern society, we think about physical activity as clustering all of our activity into a workout and that's not that but that pattern is one of sedentary lifestyle interrupted by bouts of mixed intensity working out. We give people daily totals for body weight oriented activity plus a daily step goal. The idea is that as you finish an email, when you are getting ready in the morning and you take your shower, you understand what that workout is for the day and you just accumulate your reps. Your day is now populated with activity across it versus having it all clustered into one period whenever that occurs. Not only is that reflective of more natural hunter-gatherer-like movement pattern, it also reduces the barrier for how easy it is to say yes to some exercise right now.
Jonathan Burdette - 15:02: Now you're preaching to the choir. I totally agree and it can be intimidating. My parents are 82 and it's intimidating if you tell them you need to go to your workout facility and make sure you try to get your heart rate up I mean that ... Just move. Go outside and walk like you said. With all the gadgets now, you can know if you've moved. I think that's powerful.
Dan Pardi - 15:23: For your research what's next for you?
Jonathan Burdette - 15:25: We always have lots of next steps so all sorts exit we're studying but in the beetroot juice stuff, a much bigger, more robust look at its effects on the brain, which will be a much bigger trial and a longer trial.
Dan Pardi - 15:37: When that study does come out, I'd love to have you back on to talk about the results of that.
Jonathan Burdette - 15:41: It'd be my pleasure.
Kendall Kendrick - 15:44: Thanks for listening and come visit as soon at humanos.me.