Jennifer Nelson- Mayo Clinic



Wednesday, November 10, 2010
Show Guest:
Jennifer Kay Nelson, MS, RD, LD
Director, Clinical Dietetics/Nutrition
Associate Professor of Nutrition
Division of Endocrinology, Diabetes and Nutrition

Water & Nutrition: A Vital Link

By: AroundTheWaterCooler Aired: 11/10/2010 4:30 PM UTC Description: Jennifer Nelson, Mayo Clinic Director of Clinical Dietetics; Associate Professor of nutrition at Mayo Clinic College of Medicine; and co-editor of the James Beard Foundation Award- winning “The New Mayo Clinic Cookbook” is our guest.
[Start of Transcript]
Jonathan Hall (0:15): Welcome to Around the Water Cooler. It’s a Wednesday, November 10, 2010, and our rebroadcast for November 17. We hear a lot about global warming and the economy, but in the coming decade no natural resource may prove to be more critical to human health and well-being than water. Hello, I’m Jonathan Hall, editor of There is little doubt that water is a precious resource. Experts note, however, a host of concerns from a lack of access to quality drinking water for close to a billion people on our planet to deteriorating tap water infrastructure right here in the US. But what does this have to do with you and your family’s drinking water? Well, it turns out a lot. For openers, both Vickie James, a registered licensed Dietitian and Director of Kansas-based Healthy Kids Challenge, and Cathy Nonas, a Dietitian who directs Physical Activity and Nutrition Programs at New York City’s Department of Health and Mental Hygiene have been our guests and both acknowledged that there is a body of evidence showing a high correlation between rising obesity in our country over the past 30 years and a parallel in the rise of consumption of sugar-sweetened drinks. But trying to get that message across is sometimes difficult. And here is Liza Lopes with an update. And by the way, Liza and I are coming to you from two virtual water coolers. I am in Portland, Oregon. Liza, just over the bridge from New York City.
Lisa Lopez (1:46): Good morning, Jonathan. And emails recently obtained by the New York Times under a Freedom of Information request, reveal that New York City’s health commissioner is highly committed to fighting obesity, a passion shared by Mayor Michael Bloomberg. But it also uncovered that Ms Nonas, several colleagues and a Columbia University professor expressed huge doubts about a weight gain message that got the approval of the Department of Health despite their concerns.
Jonathan Hall (2:15): We are going to talk about messaging today but you can listen to our interview with Cathy Nonas and over 50 other archive discussions at Well today, we are continuing our series on the health benefits of drinking water with Jennifer Nelson. She is the Director of Clinical Dietetics and Nutrition at the Mayo Clinic and Ms. Nelson also holds the title of Associate Professor of Nutrition of the Nutrition Division of Endocrinology, Diabetics and Nutrition at Mayo Clinic.

(2:55): Well today we are going to start. We’ve got some late breaking news. I was at the American Public Health Association’s annual meeting in Denver earlier this week, on Monday. Researchers at Yale University’s Rudd Center for Food Policy and Obesity released findings that got national attention in the media. It is a new study that reviewed the nutritional information of more than 3,000 kid meals combinations at eight fast food chains. And some of the findings were that while most fast food chains do offer a healthful side dish and beverage, the default options that employs typically serve up to customers are French fries and a soda. Now, the calories in kids’ meals that the researchers found ranged from about 300 to 1000 per meal and among teens, calories in one fast food meal would be equivalent to about a half a days worth of calories. So we are going to talk about that study today. I want to do a reference to another. By the way, that study can be found at And in a new study out yesterday that nutrition scientists at the University of North Carolina at Chapel Hill weighed in, researchers concluded that because obesity is so difficult to treat and focus that we really should refocus and shift to prevention. Penny Gordon-Larsen, who headed the study, commented that, “We really need to prevent kids from becoming obese teens, and then prevent those teens from becoming severely obese adults.” Writing in the journal of the American Medical Association, researchers suggest that girls should be the number one target for obesity prevention efforts. And finally, last week, a team of researchers at Harvard predicted that Americans will keep growing fatter until 42% of the nation is considered obese. And another part of the study conclusion was that having fat friends is part of the problem.
(4:55): The importance of that research is that it contradicts other experts who say the nation’s obesity rate has peaked. So Jennifer Nelson, welcome to our show. We would love to have you comment on all this new research.
Jennifer Nelson (5:10): Well thanks, Jonathan, and hi, Lisa. How is everyone today?
Jonathan Hall (5:14): We’re great.
Jennifer Nelson (5:16): Oh, great. Why don’t you lead me through what you are most interested in?
Jonathan Hall (5:20): Well, I think the idea here is that — and I will go right to a trade journal, Advertising Age, that reaches out to the advertising community. They found that the quick response to these studies was that “Hey, we’re great! We’re kind of — we’re on healthy stuff!” But Ad Age concluded there wasn’t any substance to what they were saying and I think the real concern on our show, I mean, you know, week after week we pass out the message that drinking water is important and it’s all about trading calories, so perhaps, if you could just speak on that point.
Jennifer Nelson (5:58): Well, you are exactly right, Jonathan. It does boil down to choosing foods and beverages wisely. I believe, personally, that we are in a crisis mode. Whenever you look at alarming statistics of obesity and the fact that they’re climbing — and I do question the statistics that say that it has leveled off. I know that it is climbing in our children and youth and. You know, downstream from that, in 10 or 15 years, will be unhealthy adults. So you do need to choose your foods and beverages wisely. Secondly, it is important that we also address the other side of the equation, and that’s physical activity. All too often, we’ll concentrate on one side such as calorie intake and not concentrate enough on getting off our butts and moving.
Jonathan Hall (7:03): Yeah, well let us take a step back. We know that water is essential to good health but how much water should you drink each day? You know, it is a simple question but the answers are not so easy. We are going to get to the bottom of this on today’s show and I guarantee you that our listeners will be reaching for a glass of water, probably during and definitely after the show. There is a chart at the Mayo Clinic’s website that depicts the human body and all the body systems that require water to function optimally. Liza, help us out here.
Lisa Lopez (7:36): Sure, Jonathan and Jennifer. Water is our body’s principal chemical component and makes up about 60% of body weight. The Mayo Clinic chart we’re looking at notes that water flushes toxins out of vital organs, carries nutrients to cells and provides the moist environment for ear, nose, and throat tissues. Water regulates body temperature and protects body organs. And it’s water that carries nutrients and oxygen to cells. And water acts to lessen the burden on kidneys and the liver by flushing out waste products.
Jonathan Hall (8:08): Okay. So, that is the top line. Jennifer, can you share with us some additional details on the relationship and importance of ingesting water to health in general and the function in the body?

Jennifer Nelson (8:19): Sure, sure. Well in addition to all of those body processes, there are other important aspects of water in our bodies. You know, if you think about it, it lubricates our eyes and it keeps our body joints bending smoothly. And it’s also very essential to digestion. In other words, the food that we take in needs water in order for our body to break it down and absorb it. And also, Jonathan and Liza, as you’ve pointed out, we know that water can be the carrier of many unwanted excessive calories such as in sweetened sodas and coffee drinks and that sort of thing.

Jonathan Hall (8:59): That is an interesting take on that. I haven’t thought about water as an enabler, but you are right. And Jennifer, so it is true that all the body’s tissues and organs benefit from increased hydration while a lack of water can lead to dehydration and that then can impair normal functions. While many people seem to understand that, it seems to me that people often fail to understand that even mild dehydration can drain your energy, make you tired. And isn’t this sort of like a mouse on a treadmill? People who feel tired start to reach for caffeine and energy drinks for a quick fix when they might be better off just consuming a little more water throughout the day.

Jennifer Nelson (9:42): Well, I agree, Jonathan. You know, it is conceivable that mild dehydration can zap energy and I have seen lots of people drinking excessive amounts of calorie-containing beverages for the ‘lift’. But the body water works in subtle ways, however, and our conscious mind wants and craves the quick fix but water can satisfy that and you don’t necessarily need the caffeine and those other quick energy boosts. And so, what we might think as a quick fix, you know, really isn’t. We can get the same thing with a good drink of water.

Jonathan Hall (10:28): Yeah, and I think you are right — that immediate kind of need that our mind responds to when our body maybe is craving the other. The other extreme was highlighted recently by the Australian pop singer, Kylie Minogue, during her trip to America — and Liza has that report.

Lisa Lopez (10:47): Well, in preparation for her high profile appearances that included Dancing with the Stars and The Tonight Show with Jay Leno where she performed Get Out of My Way and her scheduled performance on the X Factor, Kylie Minogue has been drinking a lot of water. In fact, her diet plan involves drinking nothing but water flavored with freshly squeezed lemon or lime and eating one low calorie meal a day. Apparently, when she wants a treat, she freezes citrus water into ice cubes, according to Heat Magazine.

Jonathan Hall (11:17): Well, I like a little lime in my Pellegrino as well, but I’m guessing Jennifer, this is not a diet that you or the Mayo Clinic would recommend.

Jennifer Nelson (11:26): Oh, that is so true.

Jonathan Hall (11:27): But my interest in doing this show revolves around my passion for drinking water as part of a healthy diet, and I tend to sip a glass of water or switch to tea most of the working day. Is there a point though where you might be placing too much stress on the kidneys by consuming too many liquids?

Jennifer Nelson (11:49): Jonathan, it’s not common to stress the kidney out by consuming too many liquids. The kidney is an organ that’s designed to handle fluid. Now, sometimes you run into difficulty when you don’t get enough fluid filtering through your kidneys. But let us turn it around. If you have kidney problems due to an underlying disease or damage, or heart problems, or liver problems, these are all mechanisms that help you regulate fluids in your body. And so if you have damage to some of these organ systems, you need to be mindful of drinking too much fluid. So, individuals who have existing kidney problems, take certain blood pressure medications, have heart disease or liver problems, need to really follow some fluid restrictions and be sure that they follow their doctor’s recommendations. Also, your level of physical exercise will determine your need for water, the weather, how much you perspire etc., etc.

Jonathan Hall (13:00): Yeah, I wanted to get into that, as a matter of fact. We know that recommendations for drinking water vary according to temperature outside and personal exercise. But other than that, how much water does the average healthy adult need, and what counts? Do I have to just drink water or do foods count too?

Jennifer Nelson (13:19): Well, anything that is liquid or contains liquids does count. So, things — you know, beverages, juices, milk, soups, fruit, vegetables, all of those contribute towards meeting your need for liquid for your body’s requirements. Foods, it’s estimated — especially fruits and vegetables, can provide up to 20% of your need for fluid. Now, when it comes to actual recommendations, it is kind of, I don’t know — a hit and miss, so to speak. You know, it will vary upon the individual or it will vary upon your age, your rate of growth. But the Institute of Medicine has estimated that adult men, and these are men who are age 19 and up, need about 13 cups or 3-1/4 quarts of fluid a day. Women, age 19 and up, need about 9 cups, you know. Of course, there is always going to be a range and you need to be mindful of that. For children…
Jonathan Hall (14:29): Well, yeah, what about children?

Jennifer Nelson (14:31): It is a little bit less with boys age 9 to 13, about 8 cups, 14 to 18, it jumps up to 11. And then, as I mentioned, after age 19, it goes up to 13 cups a day. For girls, age 9 to 13, it is seven cups, 14 to 18 year olds, 8 cups, and age 19 and on about 9 cups.

Jonathan Hall (14:57): Okay. You know, there is another kind of crisis, in a way, growing and according to a recent report published by Reuters, despite efforts to limit availability, public elementary students in the US have more, not less, outlets to buy unhealthy beverages at school than in the past.
Jennifer Nelson (15:17): In fact, Jonathan, Reuters reported just a few days ago that while the number of vending machines have remained stable, that during the three years of the study — that’s 2006 to 2009 — that access to stores or snack bars or even ala carte cafeteria lines rose significantly. And US researchers said last week that by 2009, 61% of students could buy high-calorie drinks from vending machines or school stores compared with 49% only two years prior to that.
Jonathan Hall (15:49): Yeah, you know, Jennifer. We’ve tracked this because a few years ago a Clinton initiative — word reached out to the beverage industry and they agreed to cut back on these “bad-for-you” beverages in school but this study seems pretty alarming. What’s your take?
Jennifer Nelson (16:06): My take, I agree. You know, it is alarming. One of the things you have to keep in mind though is that agreements aren’t necessarily followed, you know? Unfortunately. And it has been a number of years since President Clinton did put out the initiative and ask food manufacturers and companies to cut back on these sorts of things. It’s also alarming how the rates childhood obesity have continued to climb. Although many schools are being proactive with healthy foods not all of them are. And they also struggle with fitting physical activity into the school day just as work sites have difficulties with getting physical activity into their environments. Exercise, as well as what you have access to in terms of eating and drinking is critical. It’s a critical component to the obesity issue.
Jonathan Hall (17:07): Yeah, it’s pretty — I think the evidence is very strong for a comprehensive approach. Because of how information gets repeated in the blogosphere, is why I’m going to ask you about the next question. There is a lot of room for misrepresentation, I feel. For example,, a social website, published a blog this summer produced by BioDrugs, an online website that sells what it calls “nutraceutical products”. The BioDrugs’ blog claims to have been viewed over 37,000 times. Liza, tell us about it.
Lisa Lopez (17:45): Well, the BioDrugs’ commentary cites research done by Dartmouth Medical School physician Heinz Valtin, a kidney specialist and author of two textbooks on the kidney and water balance. About nine years ago, Dr. Valtin investigated the origin of the “drink eight glasses a day” rule of thumb and dubbed it “a myth” that lacks any scientific evidence to support it. Because of the website, we now know that, and an Iranian-born physician popularized the advice – – that is, to drink the eight glasses of water each day — in a best selling book, “Your Body’s Many
Cries for Water.”
Jonathan Hall (18:21): And Dr. Valtin has garnered a lot of media attention during the years dispelling this eight glasses myth. He claims to have had no intention of causing this huge ruckus which he has caused but even so a couple of years ago he reaffirmed his original conclusion that except under special circumstances we probably, currently drink enough water — possibly more than enough. But Jennifer, here is what we would like you to comment on. It’s been a popular assumption that except in special cases, it’s a good idea to let your thirst be your guide. But the BioDrugs commentary did not stop with calling the eight glasses rule a myth. It went on to label the idea that by the time you become thirsty you may already be slightly dehydrated — also a myth. Can you comment on that?
Jennifer Nelson (19:09): Okay. Well, first of all, our bodies are geared to function within a range of water intake as well as a range of nutrient intake and there are times that we eat and drink well and there are times that we don’t. And so the average person does have regulatory ways that help us adjust to these fluctuations. Thirst is just one of those ways. However, we do know that as you age, you can’t necessarily let thirst be your guide. Also, you know that in our busy lifestyle, we sometimes forget to even eat let alone drink and so we need to be more mindful. You know, when it comes to the eight glasses of water a day or eight 8-ounce glasses a day — it is a rule of thumb. It gets you in the right direction. You can argue the particulars but I just think that it’s really — that degree of precision leads us down a path that we don’t want to go down. Our bodies are amazing mechanisms and if we are mindful of them and we follow some general guidelines, for the most part we do okay. There are those exceptions. So I mentioned people who have underlying medical problems, are on medications, or work in extreme climates, or exercise a lot — you know, they have different rules of thumb.
Jonathan Hall (20:42): Yeah, I appreciate that clarification because I think you’re absolutely right — to just call it black or white just doesn’t do anybody any good and to know that it’s a great, perhaps rule of thumb, I think, is very beneficial. You mentioned ageing. I want to return to that Mayo Clinic chart that Liza referenced earlier. When an ageing population — with this ageing population — a growing concern for many people today are their joints. In fact the chart says that water helps lubricate joints.
Jennifer Nelson (21:12): But at, Jonathan, Dr. Kevin Stone, an orthopedic surgeon and the founder of Joint Juice, explains that the benefits of using his product — he says it works as a supplement to which should be occurring naturally in the body, helping cartilage tissue absorb water. He also explains that there is a second compound, chondroitin, which also occurs naturally in healthy joint tissue and is a major component of joint cartilage. Together, they stimulate the body to produce a third compound, glycosaminoglycans, which according to Dr. Stone act as a powerful water magnet. These magnets increase the water content of the joint cartilage, keeping it healthy and lubricated.
Jonathan Hall (21:55): And at, you can take a joint health test and/or buy a 30-day supplement for about a buck a day. So, Jennifer can you help us understand the role water has in building cartilage and when and if it’s a good idea to supplement glucosamine and chondroitin, which at least you mentioned are produced naturally in the body.
Jennifer Nelson (22:17): Oh, wow! Okay, well first of all, I’m not a rheumatologist and so…
Jonathan Hall (22:22): Okay. Fair enough.
Jennifer Nelson (22:23): And so I don’t have an opinion about Joint Juice. However, from a nutrition standpoint, we all agree that if we nourish our bodies properly over the years that we are going to be in better shape as we age. It’s like we start out as a new car and unless we lubricate our car and change our oil and do all the maintenance sorts of things that need to be done, we are going to get more miles
out of our bodies. And so, adequate fluids and good nutrition throughout a lifetime is critical. As we age though, parts break down, okay? And there have been studies and the Natural Medicines database, which is a highly regarded summary of research that goes on, shows that there is consensus in the research that chondroitin, which is one of those components that you mentioned before, when combined with glucosamine, it can help improve symptoms of osteoarthritis and it may slow down joint deterioration.
Jonathan Hall (23:35): Okay.
Jennifer Nelson (23:36): But again, prevention is good.
Jonathan Hall (23:39): You know, I am going to pause here quickly to take one call. Paul, you’re on the air.
Paul (23:45): Hi! Yeah, my name is Paul and thank you so much for giving me this opportunity. You know, I am hearing a lot of great benefits of just drinking water through out the day and you know, for myself and my family I have home delivery, so I have water available all the time at home. But when we are out and about in society , you know, water is not always available. Especially, clean water to drink, you know. So, I mean, what are some things that — especially my kids at school– how do we control their choices at school and things like that?
Jonathan Hall (24:23): It is a good question. How do we monitor our children’s water intake?
Jennifer Nelson (24:30): Yeah, this is Jennifer. One of the ways that is increasingly popular is to send some water along with your child to school — send a water bottle. If you are concerned about the local water supply, we do have regulatory agencies in place to enforce minimal standards of water but we all know that we all have our own separate concerns about whether or not that meets our standard of water safety or water purity. But if you can send along a water bottle, it’s increasingly popular and you see them attached to back packs of kids and all of that.
Paul (25:15): Great. So, you just mentioned water quality. I mean, do you have a preference over what our bodies would consider best water, over bottled water or tap water?
Jennifer Nelson (25:31): I honestly don’t. I think, what’s most important is that we are drinking safe water and with the regulatory agencies that are in place, we are assured of a minimum level of safety. Okay? Be it from the tap or be it from bottled water. We also know that often times what we buy as bottled water may not be regulated. It may come from the tap already and so it’s really difficult. What you ask is kind of a difficult question to answer because it is just depends upon where you are and federal regulations, local regulations, if you have well water — that sort of thing.
Paul (26:17): Right.
Jennifer Nelson (26:18): I want to kind of go back to — that our bodies are pretty amazing and we can deal with kind of a range of intakes. And the kidneys are wonderful organs in our digestion and our absorption and we don’t want to abuse our systems. Of course we would like everything to be as healthy as possible but we need to kind of give our selves some credit, too. We we’re built to be able to withstand some pretty rough stuff.
Jonathan Hall (26:49): Yeah and actually, I am going to chime in a little bit here, too. We know that in this country there has been a backlash against bottled water packaging and that the industry is working on that. I put the question to Kelly Brownell, who is Director of the Yale’s Rudd Center for Food Policy and Obesity, just two days ago. I have asked him, with all this backlash and the sort of
feeling of guilt that one gets for drinking bottled water, isn’t it more important that we really reach out to what we consider to be an acceptable source and that the most important thing is to drink water. And he said he passionately concurred with that. And I think Jennifer is pretty much on the same page. Jennifer any wrap up thoughts here? Unfortunately, I wanted to ask you a lot of questions. Can you just briefly mention what you consider to be some of the unhealthy beverages out there? We talked a lot about what is healthy and the importance of water and drinking it — is there anything that you would alert listeners to, to absolutely stay away from?
Jennifer Nelson (27:59): Well, I think because obesity and let’s put it on the context of what we’ve been talking about. I think because obesity is such a concern, we need to be very mindful of the calories that our beverages are dragging along with them. We want to make sure that, first of all, that our beverages are not tipping the scale into over consumption of calories. So, water is your perfect basis because it is calorie-free. On the other hand, juice? You know, juice has gotten a bad rap, mostly because we abuse it. We take in much, much more than we need. Remember those little jelly jars that our grandmas used to have, those little teeny, tiny shot glasses. That’s the proportion advice that that we should be drinking when we drink juice. If you have a couple of them a day, you are not going to get in too many calories but you are going to get in excellent nutrition, vitamins, minerals, other essential elements with that. We can’t overlook milk, be it cow milk, soya milk, almond milk, rice milk — those are good protein sources. But again, if you over consume you might get into trouble. You mentioned tea. Tea is fine. Just don’t load it up with sugar and cream and that kind of thing. Coffee could be okay as well, but there is some stuff coming out on coffee drinks too and those might be too high.
Jonathan Hall (29:31): Mostly the high calorie ones, yeah.
Jennifer Nelson (29:33): Yeah.
Jonathan Hall (29:34): You know, Jennifer, apologies. We’re going to have to leave it here. This has been a great hour. I hope you will return at a later time.
Jennifer Nelson (29:40): I will be happy to.
Jonathan Hall (29:42): Oh, fantastic! That’s it for today’s show, for Around the Water Cooler hosted on Blog Talk Radio, the first and largest online radio citizen broadcasting network. I’m Jonathan Hall along with Liza Lopes. Thanks again. A big special thanks to Jennifer Nelson of the Mayo Clinic for being our guest today and join us again next Wednesday, November 17, for a re-broadcast of today’s show. Thanks to Sherry Sanland for handling today’s production and thanks to those of you who phoned in and who were chatting with us online. Sorry, we didn’t get to all your calls. Mark your calendars now to join us, December 1st when Yale Professor Shimon Anisfeld will be here to discuss his book, “Water Resources,” and on December 15th Paul Schwartz, the National Policy Coordinator for Clean Water Action will be back with us. Please join us for that. That’s Wednesdays, 11:30 a.m. Eastern time and 8:30 a.m. Pacific time for our next Around the Water Cooler show.
[End of Show Transcript


About Me

Jonathan Hall is a drinking water advocate. He blogs at and has worked as an independent strategy and social media content consultant.