The Best Foods for Eye Health, with Dr. Kathi Head

Dr. Robert Rountree:

This is The Thorne Podcast, the show that navigates the complex world of wellness and explores the latest science behind diet, supplements and lifestyle approaches to good health. I'm Dr. Robert Rountree, Chief Medical Advisor at Thorne and Functional Medicine doctor. As a reminder, the recommendations made in this podcast are the recommendations of the individuals who express them and not the recommendations of Thorne. Statements in this podcast have not been evaluated by the Food and Drug Administration. Any products mentioned are not intended to diagnose, treat, cure, or prevent any disease.

Hi everyone, and welcome to The Thorne Podcast. This week we're talking about the fascinating world of eye health, one of our five key senses, and we'll explore everything from common eye conditions to proactive measures for maintaining optimal vision. Joining me in this discussion is Dr. Kathi Head, Thorne's Executive Director of Medical Media and a naturopathic doctor. You probably read Kathi's work on Thorne's Take 5 Daily blog, where she is a prolific contributor. Kathi, welcome back to the show. How are you doing?

Dr. Kathi Head:

I'm doing great. How are you, Bob?

Dr. Robert Rountree:

I'm good. Been an interesting season, always having fun keeping up with the weather and Colorado, which is unpredictable from hour to hour.

Dr. Kathi Head:

Yeah, even more so than here in Idaho, I think.

Dr. Robert Rountree:

Yeah. All right, so let's get right into it. Eye health and vision is something a lot of us take for granted. So what should we be thinking about in terms of maintaining healthy vision? So give us some pointers on what's involved in taking care of our eyes.

Dr. Kathi Head:

Well, I think one of the main things is helping to protect your eyes from external attack, by UV light, from the sun, or by helping protect from the high-intensity blue light that you get from your computer screen, your tablets, and even from your phones, also your TV if you still are watching TV.

Dr. Robert Rountree:

What's that, a TV?

Dr. Kathi Head:

[Laughs] I still watch TV.

Dr. Robert Rountree:

Yeah, no, I do too.

Dr. Kathi Head:

I still have a cable service that comes free with my condo, I do. So yeah, there are a lot of things that can be done along those lines to help protect your eyes, from wearing sunglasses to using protective blue-light filtering screens on your devices. I think you can, with your phone, you can actually just get an app that has a protective filter.

Dr. Robert Rountree:

I actually use one called f.lux, L-U-X, on my desktop that automatically adjusts the color frequency depending on the time of day, and it's pretty cool. It's free.

Dr. Kathi Head:

And does it get really dim at night? Or how does that work?

Dr. Robert Rountree:

It's not dim, it's just a different tint. So less blue, I guess.

Dr. Kathi Head:

It's something that I always think that I'm going to do, that I don’t get around to doing.

Dr. Robert Rountree:

Well, this one I just installed on the computer, and then I've forgot about it and been on there for years. So I guess the first thing is you should tell me, "Bob, don't be working at the computer at 10 o'clock at night." I imagine you might suggest that.

Dr. Kathi Head:

Bob, don't be working at your computer at 10 o'clock at night.

Dr. Robert Rountree:

OK, well, so my wife will agree with you.

Dr. Kathi Head:

You can say, "Kathi, don't fall asleep with your TV on."

Dr. Robert Rountree:

Yeah, this is true. I've got to say, years ago I did volunteer work in West Africa in a lovely country called Ghana, and they had a very high incidence of cataracts near the equator. There's a lot of bright sun all the time. And I noticed this was some time ago, a few decades ago that people did not wear sunglasses. And I started asking around, "Well, why don't you wear sunglasses?" And the response I got was, "They're not cool." Nobody had ever promoted sunglasses as being the cool thing to do. And I thought, well, that would be a nice marketing campaign to put up posters of famous people wearing sunglasses just so we can get people to do that.

Dr. Kathi Head:

Exactly.

Dr. Robert Rountree:

What kind of difference does it make to use sunglasses? Is there good data that prevents cataracts?

Dr. Kathi Head:

Well, yeah.

Dr. Robert Rountree:

Well, yeah.

Dr. Kathi Head:

I mean, to be honest with you, I haven't searched the research on sunglasses, because I have a tendency more to focus on research that’s around foods and supplements and things like that. But what we do know is that oxidative stress – that causes free-radical formation and can cause damage throughout our body – is at the center of almost all eye conditions, from macular degeneration to retinopathies to cataracts. And so anything you can do to offset the oxidative stress, whether it's by eating foods that are antioxidants, to taking supplements, to wearing sunglasses to help protect the eye from the UV light that then causes the …

Dr. Robert Rountree:

Oxidative stress, yeah.

Dr. Kathi Head:

... oxidative stress in the first place is something that is desirable.

Dr. Robert Rountree:

So you mentioned antioxidants, but not all antioxidants are created equally, right? Are there particular antioxidants that seem better suited for eye health than others?

Dr. Kathi Head:

Yes, actually there are. And what I find really interesting about some of the antioxidants that benefit eye health is that they're actually part of the eye. If you want to talk about you are what you eat, you can really say that about your eyes. Your eyes are what you eat. And by that I mean there are certain carotenoids called lutein and zeaxanthin in particular too. They're found in foods like red and yellow and orange fruits and vegetables. And they're actually in other foods too, not just fruits and vegetables. Lutein, the highest foods in lutein are corn and egg yolks. And zeaxanthin, they're high in zeaxanthin too, but the highest vegetable is orange peppers like orange bell peppers or orange sweet peppers. It turns out it doesn't even have to be red and yellow fruits and vegetables; even green leafy vegetables are high in these particular pigments, but apparently the chlorophyll and the green leafy vegetables is such a strong color that it blocks the color of the orange and yellow colors that are in there.

But what happens with lutein and zeaxanthin is there's an area in the back of your eye called the macula, and it's right in the middle of the retina. And it's important for you being able to see what's directly in front of you and for visual acuity. Well, the macula is one of the most sensitive areas for UV-light disruption and destruction. So it's important to protect the macula. And it turns out that lutein and zeaxanthin actually go straight to the macula. The macula is if you're looking in the back of somebody's eye, if you have an oto/ophthalmoscope and you’re looking in the back of the eye, there’s a little yellow orange dot sort of in the middle of the retina. And the lutein and zeaxanthin are actually what make that dot yellowish orange because the more that's there, the denser the area is, and the less likely that UV light can get through and cause damage. So it actually just goes straight to where you want it to be, which I find really interesting.

Dr. Robert Rountree:

So if you take a supplement or if you eat very deeply yellow egg yolks, then your body somehow knows to direct it to the eye. Is there some channel, is there a carrier protein? How does that happen?

Dr. Kathi Head:

Can I look that up and circle back around with you?

Dr. Robert Rountree:

You can get back to me on that one because now I hate to say it, but when these questions come up, I lay in bed at night thinking about them.

Dr. Kathi Head:

Well, and I like to know why things work too. And I thought just knowing that the lutein and zeaxanthin were right there and the macula was enough, but apparently not.

Dr. Robert Rountree:

Part of the reason I asked this because years ago talked to an ingredient supplier that grows marigolds, and they were talking about how they feed marigolds to chickens because it makes their yolks more yellow.

Dr. Kathi Head:

Well, it's funny that you say marigold because marigold is a common source for lutein and zeaxanthin in dietary supplements usually is from marigold or often is from marigold.

Dr. Robert Rountree:

And that's a good thing. I don't think people tend to be allergic to marigolds.

Dr. Kathi Head:

Right. And it's also not something they're going to likely eat in their diet.

Dr. Robert Rountree:

They're not going to eat it otherwise.

Dr. Kathi Head:

Yeah. So I mean, you can certainly get a lot of lutein and zeaxanthin by just eating vegetables and fruits that are high in lutein and zeaxanthin.

Dr. Robert Rountree:

Or egg yolks.

Dr. Kathi Head:

Correct, yeah.

Dr. Robert Rountree:

It seems like eggs are one of those foods that falls in and out of favor monthly or perhaps weekly. Like, "Oh, this month eggs are good for you.” Next month, “Eggs are bad for you."

Dr. Kathi Head:

I choose to ignore the eggs-are-bad-for-you part. I eat eggs practically every day. But yeah, eggs are good. In my book, eggs are good.

Dr. Robert Rountree:

Yeah, I think eggs are good. I mean, don't eat a dozen a day.

Dr. Kathi Head:

And if you want your lutein and zeaxanthin, you're not going to be able to go with the egg white, egg substitute, egg white stuff. You need the yolk. It's the yolk that has the lutein and zeaxanthin in it.

Dr. Robert Rountree:

So first of all, the lutein and zeaxanthin are part of the larger carotenoid family, right?

Dr. Kathi Head:

Right.

Dr. Robert Rountree:

That includes things like beta-carotene, lycopene, etc. But you're saying that it's specifically the carotenoids, lutein and zeaxanthin, that are helpful for eye health. In other words, do you get benefit for your eye from eating beta-carotene or does that?

Dr. Kathi Head:

Oh, yes, yes. Beta-carotene is an antioxidant. Any antioxidant is going to be beneficial for the eye. And beta-carotene, actually, vitamin A, which converts to beta-carotene is really important for eye health, too. And this is another situation where the vitamin A is actually a part of the structure of the eye. Vitamin A is part of a molecule called rhodopsin, which is in the rods of your eye. And the rods are important especially for you to be able to see at night. And it's also in another pigment or in the cones of the eye called iodopsin. That is important for seeing during the daytime. So vitamin A, what happens when light hits is that one form of vitamin A gets converted to another form. And interestingly, and this takes place in the retina, and what's another name for vitamin A? Retinol. So there's no, that's not a mistake that there's a cross naming going on there between retin. Don't ask me which came first.

Dr. Robert Rountree:

The chicken or the egg yolk.

Dr. Kathi Head:

The egg yolk.

Dr. Robert Rountree:

The egg yolk. So do people have to take the pre-formed retinol vitamin A, or if they take beta-carotene…? I assume vegetarians don't take vitamin A. So how does that work?

Dr. Kathi Head:

Well, in order to get the actual activity of the retinol conversion and the rods and cones, it does have to be vitamin A. Beta-carotene is another. It's converted to beta-carotene, which is an antioxidant, which is going to have benefits as well. And that's probably why your mom told you to eat your carrots or you'd go blind.

Dr. Robert Rountree:

Which I wasn't that big a fan of when I was a kid. But I love carrots now. I like those little baby carrots, right, because they're great snack. As far as I can tell, they seem to be good for you this month, eggs and carrots.

Dr. Kathi Head:

Well, and carrot juice. I like carrot juice more than I like just to gnaw on a carrot. And it turns out that in order to get the beta-carotene, the best way to get it from your food is from either cooked carrots or carrot juice as opposed to raw carrots. Oftentimes we hear that the raw vegetable is better and has more vitamins and the heat destroys it and all that. Well, in the case of carrot, it appears that the beta-carotene is more available either if you cook the carrot or if you juice it.

Dr. Robert Rountree:

Important information.

Dr. Kathi Head:

Just a little aside.

Dr. Robert Rountree:

What about lycopene? Is that good for the eye or is that not one that's... You don't hear about it that much for eye health, but is that…?

Dr. Kathi Head:

It's not as much thought of for eye health. Certainly, there's a lot of good research on it for prostate health and for cardiovascular health. Now you're making me want to go check in PubMed and see if there's anything on lycopene and eye health.

Dr. Robert Rountree:

OK. But it sounds like the green leafy vegetables and the orange peppers and egg yolks and corn are all kind of take-home messages. But I'm wondering, can you really get enough from food if you want to prevent a serious condition like age-related macular degeneration or if person is in the early stages of ARMD? I know there's a huge industry out there selling these AREDS, A-R-E-D-S supplements. So there must be a belief out there that supplements do something more than what you can get food. What's your opinion on that?

Dr. Kathi Head:

Actually, that is one area where you can actually get a reasonable amount of actually what I consider a therapeutic amount of lutein and zeaxanthin from the vegetables. I had at one point, I'd written a long article in Alternative Medicine Review, actually a two-parter on eye health. I talk a lot about lutein and zeaxanthin and I had a little chart that had how much of each of those is in certain vegetables. And unfortunately I don't have it sitting here in front of me now. But I do recall being impressed that you could get several milligrams of lutein and zeaxanthin in servings of those vegetables and fruits. And in the studies that looked at these carotenoids for eye health, they're usually looking at around at least 10 mg a day of lutein and a couple of milligrams a day of zeaxanthin. Yes, you can, if you're really diligent about eating your carrots and peppers and corn and eggs and green leafies, don't forget green leafies. You could probably get enough of that, but I don't know that many people that do that diligently day after day.

Dr. Robert Rountree:

Right, diligent is the word there. Two other things I want to ask about before we run out of time. One is zinc and the other one is omega-3 fatty acids. So I'm wondering if you could make a comment about the benefits of those.

Dr. Kathi Head:

Well, omega-3... I would like to talk about bilberry, too, if you have a moment.

Dr. Robert Rountree:

OK, bilberry.

Dr. Kathi Head:

But omega-3 fatty acids are important, particularly DHA. So of the omega-threes, we have EPA and DHA and about 70 percent of the fatty acids in, for example, the cell membranes of the rods in the eye are made up of DHA. DHA is important for maintaining eye health. It's also important during development of a fetus for developing the eye. So DHA is essential, yeah.

Dr. Robert Rountree:

So if somebody's going to take a supplement or eye health specifically, do they want to take a high DHA supplement?

Dr. Kathi Head:

Yeah. Probably if you're really focusing on eye health, you're probably going to look for one that's maybe even higher in DHA than EPA. A lot of supplements, you'll look at EPA as being the 300-something of EPA and 200-something of DHA, but for specifically eye health and also maybe brain health, you might be looking at the reverse, a higher DHA than EPA amount.

Dr. Robert Rountree:

And what about bilberry? What is bilberry?

Dr. Kathi Head:

So bilberry, it's similar to blueberry, and it's a berry with a dark blue-purple pigment, which it turns out this is another situation where the pigments in the plant seem to be really important, and bilberry seems to have an affinity for the retina. And there's certain flavonoids in bilberry called anthocyanin flavonoids. They're found in purple, red and blue fruits and vegetables. So they're found in all the blue and red and purple berries, but they're also found in like purple cabbage and now you can get purple cauliflower, all sorts of things like that. What these flavonoids do, one of the things they do is help strengthen the blood vessels. They don't leak as easily. It's one of the eye conditions that can happen is a retinopathy where the blood vessels actually leak and bleed into the back of the eye. And so bilberry can help strengthen the blood vessels so they're not as leaky and also improve circulation. And along that same line, a grape seed extract can do a similar thing. Well, there's been a fair amount of research on zinc in terms of helping protect from macular degeneration. What's been your experience with zinc like with patients? Have you used that with patients?

Dr. Robert Rountree:

I mean, I definitely use it as part of an eye health protocol, so I don't use it by itself. So I'm having somebody do the carotenoids, I'll always do at least 15 to 30 mg of zinc with it. So I would say it's just de rigueur, but I can't tell you, "Oh, I've only tried the zinc for somebody with macular degeneration for three years, and here's the percentage improvement." I can't say that. I don't know if there are any studies that have just used it as an isolated nutrient, but we know zinc is a great antioxidant if you're using it in the right dose range.

Dr. Kathi Head:

And it was part of the AREDS for I want to-

Dr. Robert Rountree:

Exactly.

Dr. Kathi Head:

... believe in several studies.

Dr. Robert Rountree:

Yeah. Which are really good studies, big studies. Great. Well, I think it's time for a short break and we'll be right back afterwards to answer some questions from our listeners.

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And we're back. So now it's time to answer some questions that have come in from the community. Our first question this week comes from a listener who asks, how much of our eye health is lifestyle based and how much is genetics? Kind of a tough question, but I wonder what your general impression is.

Dr. Kathi Head:

I think it really depends on your lifestyle and your genes as far as what percent is what, but certainly both play a significant part. And as we've talked about, there are a lot of different dietary things that can be done to support your eye health as well as simple things like wearing sunglasses.

Dr. Robert Rountree:

So genetics give you a predisposition that might put a person at higher risk for something like macular degeneration. But what you're saying is that there are things you can do. We talked earlier about wearing sunglasses and how that might help prevent cataracts. And the same thing with diabetes. If you have better blood-sugar control, then you're less likely to get cataracts. Am I right about that?

Dr. Kathi Head:

Yeah. And the other thing that diabetics get of course is a diabetic retinopathy where they have a tendency to have bleeding in the eye. That's where bilberry could come in handy.

Dr. Robert Rountree:

But it's not a sentence. Maybe the person's got the genes that predispose to type 1 or type 2 diabetes, so they're more likely to get it, but that can be prevented.

Dr. Kathi Head:

Yeah. Particularly, type 2. And if you know that you have the genetic predisposition for type 1, I'm sure there are some lifestyle things that could start early in life that could hopefully help prevent that.

Dr. Robert Rountree:

Yeah. So you know what I think you've just done is you've rephrased the question. So instead of saying, "Well, what percentage is genetic and what percentage is lifestyle?" you're saying, "Well, again, genetics are a setup, it predisposes you, but then lifestyle has a huge influence whether you've got the genes or not." I know there's genetic disorders that can set a person up for blindness, unfortunately, but that's a special case. I think this person is asking what about the public in general? And what I would say is there's no setup I know for a person that says, "Hey, you're going to develop cataracts, retinopathy, macular degeneration, no matter what you do." I think that's how I'd rephrase that question. Do you agree with that perspective?

Dr. Kathi Head:

Yeah. Oh yeah, totally.

Dr. Robert Rountree:

So what about color blindness? Is that a genetic disorder or can you have the ability to distinguish colors and lose it?

Dr. Kathi Head:

Both. Some people are born color-blind. It's a gender-associated trait. So boys are more likely to be color blind than girls. However, there are certain things that can happen. For instance, cataracts. As somebody develops cataracts – which it seems to be happening more and more; I don't remember my parents having issues with cataracts until I think my dad was in his 80s and had some cataract surgery at that point... But at any rate, I'm getting off track. As people developed cataracts, their color vision becomes less clear. The colors are more muted oftentimes.

Dr. Robert Rountree:

I would also throw in that there's certain drugs, certain medications that can cause temporary color blindness while the drug is in the system. There's an example, Viagra. A certain percentage of people when they take Viagra or drugs like that, they're called the phosphodiesterase inhibitors, they will get temporarily color blind because the same enzyme that's involved in doing what it does for sexual function, that same enzyme is also active in the eye. So that's a temporary kind of thing, but it is something people should be aware of. So they don't happen to take Viagra for other reasons and then go, "Oh my gosh, what happened to my color sensation?"

Dr. Kathi Head:

I did not know that. That's really interesting.

Dr. Robert Rountree:

Yeah, I think it's in the drug warnings around the drug. So you mentioned cataracts. Next question, what are cataracts and how do they occur?

Dr. Kathi Head:

Well, cataracts are a clouding of the lens of the eye. It's usually a gradual process, and it's typically age related. UV-light exposure is a big cause of cataracts. As you mentioned, in your trip to Africa, it seemed like there was a high risk for cataracts, and you discovered it's because they didn't think sunglasses were cool. So certainly age is a factor and exposure to UV light, also exposure to blue light, they're starting to find out can contribute, as well as things like cigarette smoke exposure. Anything oxidative stress is a cause for cataracts as well as for problems in the macula and the retina.

Dr. Robert Rountree:

And diabetics are particularly prone, yes?

Dr. Kathi Head:

Yes. Those are called sugar cataracts, and it's related to sugar converting to another type of sugar called sorbitol that gets trapped in the lens of the eye and can't get out. Whereas glucose can diffuse in and out of it, but if it converts to sorbitol, it's stuck there.

Dr. Robert Rountree:

Stuck there. And there may be nutrients that can actually block that process or keep that process from being a problem.

Dr. Kathi Head:

Right. They can inhibit that enzyme that converts glucose to sorbitol.

Dr. Robert Rountree:

So cataracts are not inevitable? They're not an inevitable part of aging.

Dr. Kathi Head:

No. Although my eye doctor told me that everybody gets cataracts.

Dr. Robert Rountree:

So if you live long enough, you probably will get it some day.

Dr. Kathi Head:

But I said, "Well, how come everybody's getting cataract surgery now when they're in their 60s and early 70s?" And he said, "Oh, they all want it because it improves their vision and they get a new lens, and so then they don't have to wear cheaters [reading glasses]."

Dr. Robert Rountree:

Now they're bionic.

Dr. Kathi Head:

Stuff like that. So now it's like a thing people are apparently wanting.

Dr. Robert Rountree:

Oh, they're asking for it

Dr. Kathi Head:

Cataract surgery, yeah. They want to hurry up and get them so that they can get new lenses. Because they have lenses that they can implant now that actually change shape. You can wind up not having to wear glasses to see far away or a closeup.

Dr. Robert Rountree:

Well, I think what I'm going to do is skip one question and come back to it later, but because we're on this topic, can your eyesight improve over time or is it just a downhill slope? So as I think the person's asking, we're getting older, is it just all downhill or is there anything positive about getting older?

Dr. Kathi Head:

Well, I think prevention is the key. So not waiting until your macula is degenerating is a good thing. And certainly there are different eye exercises you can do that can help improve your eye focus, so you can see better close up. As we age, we tend to have a harder time seeing close up without getting some dime store cheaters or something like that. And exercise there can be beneficial for sure.

Dr. Robert Rountree:

So there are vision exercises you can do because that's actually, the next question is there anything you can do specifically? And I've certainly seen books on this and I know there's videos online of exercises moving your eyes around a lot. So you're saying those exercises do help?

Dr. Kathi Head:

Yeah, and I remember some of them. I had a book that had some of those in it that I read a long while back, and one was focusing on something close up and then adjusting your focus to look at something at a distance. And just doing that back and forth several times can be beneficial. Also, sitting with your hands cupped over your eyes and actually just doing a sort of meditation, imagining being in a relaxing place can help relax the muscles around your eyes and be beneficial.

Dr. Robert Rountree:

OK, one last question. “Why do the whites of my dad's eyes always look a little yellow? He's in his 80s, should I be concerned or is it just an aging thing?”

Dr. Kathi Head:

Well, if they're actually yellow, I would want to make sure that he doesn't have anything going on with his liver. Because if your skin is jaundiced, which means your skin is yellow, then your whites of your eyes can be yellow, too. However, I would assume that if it's always like that, and I would assume that his doctor would've checked on that, but it would be good to confirm.

Dr. Robert Rountree:

Well, there's a condition that affects somewhere around 15 percent of the population, and that varies depending on where you are in the world, but it's called Gilbert syndrome. It's spelled like Gilbert, pronounced Jill Bear. What happens in that scenario is if a person goes say 12 to 24 hours without eating, then the enzyme that breaks down bilirubin, a yellow pigment, that's a result of dead red-blood cells building up in the body. The enzyme that breaks that down in people with Gilbert syndrome is inefficient. And so the longer they go without eating, the more they’ll get an increase in their bilirubin level, and it will make their eyes turn yellow.

Dr. Kathi Head:

But it would also make their skin turn a little yellow, too, right?

Dr. Robert Rountree:

That's further down the line. It will show up in the eyes first, especially if people have darker skin, that may not be obvious at all. But the eye, because the eye whites, they're white, so the yellow is more obvious there. And where it's really obvious is if you have the person fast overnight and do a blood test, their bilirubin levels will be high. So I see this very frequently in my clinical practice.

Dr. Kathi Head:

Wow.

Dr. Robert Rountree:

Yeah. It's again, 15 percent of the population depending on where you are. And the interesting thing is that if that person eats a lot of broccoli, broccoli sprouts, or takes an extract from broccoli seeds called sulforaphane, then that actually can slow that process down. Now, it varies from person to person. Some people need to eat a lot of sprouts and other people just need to eat a little bit. But a woman named Dr. Joanna Lampe at the University of Washington actually did studies that showed that people that have Gilbert syndrome, if they eat more brassica vegetables, which includes broccoli, then it will decrease that rise in bilirubin. The reason that's important is because we used to think that was a totally benign condition, but it actually is a marker for susceptibility to environmental toxins.

Dr. Kathi Head:

Wow, interesting. Yeah, I always thought of it as just an idiopathic benign.

Dr. Robert Rountree:

That's what we were all told in medical school, but then the newer research, especially based on Dr. Lampe's work says, "No, that means a person's more susceptible to other problems with their health." So I'm not saying that's what dad's eyes, his dad's eyes… I'm not saying that's what's going on, but that would be one thing I would be concerned about. And a simple blood test. So the person says, "Should I be concerned?" Well, get a simple blood test and otherwise I have seen the sclera, the whites of the eyes and people getting older, it can get kind of a brownish tint to it that may look yellow, but it isn't actually yellow. So it's not jaundice, but it should be checked out. It should definitely be something because easy and simple to look for. So I would say yeah.

Dr. Kathi Head:

Right. Just check for the bilirubin level.

Dr. Robert Rountree:

Just check the bilirubin. All right, folks, that's all the time we have this week. Dr. Kathi Head, thank you so much for coming on the podcast. It's been great to catch up with you and chat a little bit. If our listeners want to follow more of your work, what's the best place for them to go?

Dr. Kathi Head:

Well, Thorne.com has a blog called Take 5 Daily. I write regularly for that blog as do several other people here at Thorne. And we have regular contributions from our partners at Mayo Clinic as well. And that's just available at Thorne.com, click on Take 5 [Daily] at the top of the homepage.

Dr. Robert Rountree:

Excellent. Well, as always, I want to say thank you for listening and we hope that you tune in again.

Dr. Kathi Head:

Thanks for having me.

Dr. Robert Rountree:

Thanks for listening to The Thorne Podcast. Make sure to never miss an episode by subscribing to the show on your podcast app of choice. If you've got a health or wellness question you'd like answered, simply follow our Instagram and shoot a message to @ThorneHealth. You can also learn more about the topics we discussed by visiting Thorne.com and checking out the latest news videos and stories on Thorne's Take 5 Daily blog. Once again, thanks for tuning in and don't forget to join us next time for another episode of The Thorne Podcast.