Transcription
This is the nature of things. Meet filmmaker and health fanatic Brice Sage, a man on a nutritional mission. Believe me, I wasn't always this healthy. Flash back to me in high school: the fat kid with the crappy diet. So, no surprise, I'm now a bit obsessed with my health. I've always assumed if I eat a healthy, balanced diet, I'll get everything I need in terms of essential vitamins and nutrients. But is it really that simple? Maybe I do need supplements, or then again, maybe I don't.
There's growing controversy over the past 24 hours over multivitamins. They've been deemed important for high blood pressure and cancer, but they might even be dangerous. To sort it all out, Bryce hits the road to talk to the world's leading experts, and what he discovers might surprise you.
Vitamin D controls one twenty-fourth of the genome. This product has been associated with an increased risk of prostate cancer, so it's just the science. Key can be the more instances. It's my inner hypochondriac. I'm nearly 80, and I'm grateful for good genes and a diet rich in wild salmon. I've never worried about vitamin supplements as a key to a healthy life, unlike Bryce Sage, who found hope and fear, mistrust and promise when he set out to find out what science says about vitamins.
Everything I know about vitamins I learned in grade seven science, which means I forgot most of it. Today, I kind of take vitamins for granted, but how do they really work? Everyone says they're so essential, but why is that? Bryce figures the best place to start is evolutionary history. In the heart of the San Francisco Zoo, Bryce meets up with anthropologist Dr. Catherine Milton.
"Hi, you must be Catherine." Milton has spent her career studying our primate relatives and how they evolved to get the vitamins they need. She studies the dietary ecology of primates and, more importantly, what it might have to say about us.
"Katie, why are vitamins so essential?"
"Well, vitamins are involved in all sorts of important biological processes in the body. The thing is, we can't really manufacture them ourselves. We have to take in almost all of the thirteen essential vitamins in our diet. So we can't make them, and we have to have them, and they have to be in our food, or we are in trouble."
"But here's the thing: most plants and animals can manufacture many of the vitamins they need, and very few animals can't at the very least synthesize their own vitamin C. The vitamin that always comes up when people are discussing humans, of course, is vitamin C, and that's because humans and the other anthropoids, the monkeys and apes, are unable to synthesize it. Then you look around, and almost every other single vertebrate, regardless of what order it's in, is able to synthesize vitamin C. Even our household pets can make it, thanks to a gene that enables vitamin C production. But here's the big surprise: we have the same gene. The only difference is, as humans and other primates evolved, that gene stopped working."
"Why would we lose the ability to do something so essential?"
"I don't think anyone really knows the exact answer to your question, but the idea seems to be that because primates eat almost an exclusively plant-based diet, they are taking in copious amounts of vitamin C in their diet every single day. So it's really unnecessary for them to be able to manufacture or synthesize their own vitamin C. In other words, we simply didn't need the gene, so it got turned off. And the diet rich in vitamin C ensured that we and our primate cousins didn't get wiped out by the deficiency disease scurvy."
"You've been studying the diets of primates for years. What have you learned that can be applied to humans?"
"I've looked at just about everything you can look at, and there's not a single class of nutrient that I haven't found some interesting differences in. Primates take in very high quantities of dietary fiber in their diets every day. They take in much more vitamins and minerals, as a general rule, in their diet than humans do."
In fact, Milton has discovered that the average 7-kilogram monkey takes in 600 milligrams of vitamin C a day—more than seven times the recommended daily dose for the average human.
"So does that mean we're not getting enough vitamin C in our diets?"
"I certainly raise some questions as to why monkeys and apes take in so much more. We know that the general population in the United States is certainly not getting enough in their diets. Surveys indicate that up to 25 percent of North Americans are consuming less vitamin C than the recommended daily dose, and it's even worse for other nutrients like vitamins A, D, E, and B9, or folate."
"Do we really need the same micronutrients as our primate cousins? How do we even figure out what we actually require in the vitamin department? What can these numbers tell us?"
So Bryce suits up and heads to Washington, determined to decode that confusing package information.
"I've come to the nation's capital to get the inside scoop straight from the horse's mouth." Bryce gets a pass at the prestigious National Institutes of Health. He's here to meet Dr. Paul Coates, an expert with the lowdown on our daily requirements for all 13 vitamins.
"Well, that means you are exactly the man I'm looking to talk to because I need to figure out what these numbers really mean and where they come from."
"But maybe I can help you with that. The governments of the United States and Canada pull together panels to look at what are called recommended dietary allowances, and these numbers are the ones that are used to generate the daily values that you see on food labels."
"And what's the history of them? How long have they existed?"
"This process has been in place since the 1940s. In the Second World War, there was an effort to put together recommended intakes for emergency kinds of situations. The recommended requirements were first developed to ensure the men in uniform stayed healthy."
"I get that. When do we work your hurry during the Second World War? Preventing vitamin deficiency diseases like rickets was seen as a matter of national defense."
"So I think I understand these RDAs. The idea is that if I get the minimum amount of a certain vitamin, then I'll avoid a deficiency disorder like scurvy."
"It's actually a little more complicated than that. Here's the model that we use in order to determine what's adequate and what's too little and what's too much. It turns out there's an upper and lower limit for each vitamin, and they're set to ensure we get enough to stay healthy and not overdose because too much of some vitamins, like A and E, can actually be toxic. While experts still debate the sweet spot, which and how much of each vitamin we need to stay healthy, most agree the recommended amounts do prevent deficiency diseases in 98 percent of the population, assuming you follow them."
"Can the average person get everything they need to meet these RDAs with diet alone?"
"Generally speaking, they can."
"Okay, and would you be able to make me a list of the ideal perfect foods?"
"Oh, that's a little more complicated. There isn't an ideal list, but if you eat a balanced diet, you will achieve adequate nutrient status for all of those vitamins and minerals."
"If I'm going to find exactly what I need for my diet, I've got a lot of work to do. Thanks, doctor."
On the advice of Dr. Coates and armed with a Mayteen nutrition textbook, Bryce heads off to do some grocery shopping. While everyone seems to agree the best source of vitamins and minerals is our food, even that can get a little bit complicated.
"I think I've got everything I need, plus this is looking pretty nutritious, wholesome, and well-balanced to me. But I think it can handle one cheat item. Plus, my favorite cereal is loaded with vitamins."
"Welcome to diabetes and hypertension."
Sorry, doctor. Meet nutrition expert and physician Dr. David Katz, founder of Yale's renowned Prevention Research Center. Katz knows his health and the challenges facing consumers.
"Cereal companies praise the nutritious benefits of their products when they're mostly sugar with vitamins added. It's a process called fortification."
"What exactly is fortification?"
"With fortification, nutrients are being added to the food as part of the manufacturing process, so that they're not nutrients that are intrinsic to the food."
"Right, so it's not already in there naturally. Why would we fortify our food with nutrients?"
"Well, historically, fortification was about making sure the population got critically important nutrients they otherwise weren't getting enough of. A century ago, a debilitating bone disease called rickets ravaged thousands of children. Simply by fortifying milk with vitamin D, governments virtually eliminated this deficiency disorder by the 1930s. Just a decade ago, there was another move to fortify bread products with folate, mainly to help pregnant women avoid birth defects."
"But buyer beware: not all fortification practices are equal."
"The problem is, in the modern era, it's gotten very haphazard. So now it's really just vitamins and minerals kind of added willy-nilly to everything in the food supply and often used for marketing purposes."
"If the average person is getting what they need in terms of vitamins and nutrients enough to prevent deficiency?"
"Yeah, but if the question, Bryce, is about optimal nutrition, then I would say no. Fruits and vegetables have all sorts of compounds that have nutritional value that are never added for fortification, and you only get those if you eat brightly colored fruits and vegetables. So if you're asking about those nutrients, I would say almost no one's getting enough."
"I guess it goes without saying then that people should be getting the nutrients from a natural source as opposed to having them added to processed food. But it is interesting to note that even foods like broccoli, there's some concern that nutrient levels are coming down slightly because of modern agricultural practices."
"Are you serious? This is probably something I need to look into."
"An interesting story. You know what? I'm going to do that. Do you mind paying for all this?"
"What to investigate why our supermarket veggies may not be as nutritious as they once were?"
Bryce puts on his farmer duds and heads to a farm in California. Since the dawn of agriculture, we've been selectively breeding for yield. Farmers choose the seeds that grow the fastest and the largest. But is bigger actually better? It's a question Bryce wants to ask organic farmer Jake Eglin.
"Jake, I've heard that there's actually been measurable declines in the foods we eat. Is that true?"
"A lot of those heirloom varieties that were grown in the past are being bred out for varieties that yield more. Quality gets thrown by the wayside, and the quantity is really the focus."
Turns out the science agrees with Jake. As conventionally grown crops have gotten bigger over the last 50 years, their water content has gone up, and their nutrient content has gone down—anywhere between 10 to 30 percent. That means we're not getting as many vitamins and minerals per portion size as we used to, so we're not getting as much bang for our buck.
"If this would represent an heirloom organic head of broccoli like we grow on this farm, it's its impact in nutrients."
"If I can't trust I'm getting the vitamins I need from the food I'm eating, how would I know if I'm getting enough nutrients to survive?"
"So what should Bryce do? Switch to exclusively organic?"
"Not according to David Katz. Highly nutritious foods are so highly nutritious that even if nutrient levels come down a bit, they're still the way to go."
"Right. Some people get so hung up on eating organic, they think, 'Well, if it's not organic, I won't eat it,' and they actually reduce their intake of fruits and vegetables. That's a mistake. It's still better than deep-fried potatoes or—there's no comparison."
"This is the way we prepare our foods. It can actually affect the nutrient levels."
"It can affect it in different ways. For example, you cook meat; it concentrates the protein, concentrates the minerals, while water-soluble vitamins like B and C can be lost with cooking. Other vitamins seem to like the heat. For instance, the vitamin A in carrots increases by as much as 27%. Even better, a little oil with those carrots may actually be a good thing because vitamin A is only absorbed by the body after it's dissolved in fat. Also, vitamin C, which you'll get from vegetables or fruits, would actually help you absorb more iron out of the meat, which is why it's good to combine foods in a meal the way we tend to do. So lots of different interactions."
"David, this is really overwhelming, not gonna lie."
"There's good and bad in that glass, by the way. Red wine is a source of ethanol; that's what makes it alcohol, and it's hard for the body to metabolize. So we actually can drain nutrients out of the body in order to metabolize it, and all B vitamins in particular."
"All this dietary advice is just making me more afraid I may not be getting all the vitamins I need from my food. Maybe I do need to turn to supplements."
"But can I get them all in one pill? I mean, are all supplements created equal, and where do they come from?"
"Did you know that the raw honey of bees is actually a great source of all the B complex vitamins? All eight B vitamins tend to coexist in the same foods, and they each perform critical functions. B12 is key to brain development, while B9, or folate, helps to make red blood cells."
This got me thinking: is honey the kind of thing they used to make vitamin supplements? The global supplement industry is worth $68 billion, and vitamins are worth $8.5 billion in the U.S. alone. Kind of a big deal. But where do they come from? To unravel that mystery, Bryce gets a backstage pass to a local vitamin factory.
"So you said you get these things from all over the place. Can you give me some examples?"
"So vitamin A and E, we source from cod liver oil from Alaska, Greenland, Iceland, and then we get vitamin C from aloe vera. Now how about vitamin D? Do you have like a giant magnifying glass you can harness all the sun into a tablet?"
"Well, for vitamin D, we actually get it from lanolin, and that's actually from any oily, woolly mammal. The most common source of lanolin comes courtesy of these critters. Once extracted from their wool, sheep lanolin is then converted into vitamin D using ultraviolet light."
To understand how vitamin tablets are actually made, Bryce gets dressed up for the tour.
"Looking good, Bryce. This is where we dispense every individual raw material according to the formula."
"The formula for, say, like a multivitamin?"
"Yes, the daily requirements are used as a general guideline in each vitamin recipe. While most supplements are formed into dry tablets, fat-soluble vitamins like A and D are often combined with oils and formed into soft gels before being bottled and chilled."
"Well, before I start taking vitamin supplements, I guess I should find out if I'm actually deficient in any of them."
"We've been making to do that. Bryce is getting a test to measure the levels of each vitamin in his blood—a test anyone can order through a family doctor. Bryce is taking his results to Dr. Bruce Ames, a world-renowned biochemist based in San Francisco. Ames has done groundbreaking research on how low vitamin levels can impact long-term health. If anyone knows whether Bryce needs supplements, it's him."
"Looks like the results of my blood work are in. Time to find out if I'm actually deficient."
"Hi, Bruce."
"Hi, I'm Bryce. Nice to meet you."
"So may I ask how old you are?"
"I'll be 86 in about 10 days."
"Wow, and you're still working out?"
"Well, you should win your—oh yeah, keeps you healthy. Enough about you. My results are in, so I was wondering if you could tell me what they reveal."
"So your vitamin D is a little low, but I sort of expect that for a lot of Canadians. You're up north and don't get a lot of sun."
"So do I need to worry about taking a multivitamin?"
"That's complicated, but I take a multivitamin-mineral as insurance."
"You know, I want to talk about this more, so I'll meet you back at the lab."
"Great, see you there."
Ames came up with a revolutionary idea that vitamins aren't just needed to prevent deficiency diseases; they're also essential for maintaining health as we age.
"I think the main item that's keeping us all from living a long life is bad diet. Lots of shortages of vitamins or essential minerals cause DNA damage, which leads to cancer."
"Why is nature doing that?"
"One day I had this epiphany: when you have a limited amount of the vitamin, well, you put in those proteins that'll keep you alive so you can reproduce. That's what nature wants."
Ames calls it triage theory. Just as hospitals triage patients, treating life-threatening injuries before broken bones, Ames maintains that our bodies also triage vitamins. If we're low on a particular vitamin, the body assigns it to systems that maintain short-term survival rather than long-term health.
And he's demonstrated that in a study focusing on vitamin K.
"All vitamin K proteins are calcium-binding proteins, and it was discovered as a blood clotting factor. Blood clotting is really important because it bleeds to death if you didn't have blood clotting."
"Vitamin K is also essential for the prevention of calcification or hardening of the arteries."
"In a study, Ames decided to see what would happen when the body is robbed of vitamin K. Sure enough, when K levels are low, it does get rationed towards short-term survival. So when there's a shortage of vitamin K, it goes into the blood clotting proteins but not into the proteins that are protecting you from calcification of the arteries."
"So if vitamin K gets rationed, is that true for all vitamins?"
"Ames thinks that just might be the case."
"Maybe if vitamins are so important, I should be just taking away more of them. Mae West said, 'Too much of a good thing is wonderful,' but I think she was thinking about sex, not vitamins."
"I look at my diet and decide what maybe I might not be getting enough of and take a little more of that."
"Okay, I'll buy what Bruce says about too much of a good thing, but what if my body has been rationing vitamins for years? Maybe I need to top up with the trendy mega dose. I mean, I am in trendy San Francisco."
So Bryce, the hypochondriac, books in at a local health spa to get a vitamin mega-dose IV style. It's an untested treatment touted to cure everything from fatigue and hangovers to heart disease. Most scientists dismiss it as a fad, but Bryce will try anything.
"So this is the Myers cocktail. There are a thousand micrograms of B12 and a thousand micrograms of all the other B vitamins, and then about two grams of vitamin C."
"All right, load me out at a whopping 20 times the recommended daily dose."
The heaviest hit in the Myers cocktail is vitamin C, a vitamin that's been analyzed and argued about for decades.
"So is there any evidence that vitamin C is a cure for anything?"
"This lemon contains about 45 milligrams of vitamin C, or about 50 to 60% of what we're supposed to take to avoid scurvy. But some claim we need way more—that mega doses of vitamin C can cure everything from the common cold to cancer."
"Who do we trust?"
"Convite iment CBIIT the common cold. Some trials involving soldiers in training and marathon runners revealed that higher doses of vitamin C have their incidence in the cold, while another study with competitive swimmers found that regular use of vitamin C reduced the duration of their common cold."
"So should average Joes like me start upping my dosage of M&C?"
"The athletes studied expended huge amounts of energy under tough conditions, so high-dose vitamin C may have played a role in keeping them healthy. But most experts agree upping your vitamin C will do little or nothing to beat the common cold for the average person."
"So what about the cancer claims?"
Bryce has returned to the National Institutes of Health to meet with Dr. Mark Levine, one of the world's leading experts on vitamin C. Levine has been studying its impact on the immune system for more than a decade, and he's discovered that how you take vitamin C makes a huge difference to how the body reacts.
"When you take vitamin C orally, our bodies naturally utilize about a hundred milligrams or so before flushing the excess in our urine. If you inject it into your veins, something pretty awesome happens."
"If you give that vitamin C by vein, surprise! The amount that the body has temporarily can go much higher. Nobody knew when vitamin C is given by vein, the body's exquisite ways of controlling how much we have are short-circuited for hours. Only when there is enough of it do we form hydrogen peroxide, and that hydrogen peroxide leads to cancer cell death. And we know this because we have measured this again in the laboratory and in animals. In studies of mice with ovarian, brain, and pancreatic cancer, high-dose vitamin C and its hydrogen peroxide by-product reduced tumors by an astonishing 50%. Early human trials indicate that vitamin C IV therapy may also be effective for us."
"What are the next steps?"
"We have to learn doses of ascorbic acid and work with chemotherapy. The patients' tumors get smaller, the patients feel better, or both, and those studies are going to happen."
So Levine's research suggests that mega-dose vitamin C may have potential as a cancer treatment. But what does he think about using it to treat a cold?
"Do I take it when I get a cold?"
"No."
"But what should Bryce do?"
"If you wish and you want to supplement, then your kidneys are fine and you don't have oxalate renal stones, go ahead and take yourself a mega dose if you want."
"Okay, mega dosing may benefit people who are really sick or deficient in a particular vitamin, but the jury's still out for average Joes like me."
To check that out, Bryce rushes off to meet North America's leading vitamin skeptic, Dr. Paul Offit, a physician who's investigated almost every supplement claim and found many to be false, some downright dangerous.
"Sorry I'm late. I was in a bit of a rush, so I had to get a burger and fries. I know it's not the most nutritious; it doesn't have a lot of vitamins, but I did come prepared with my vitamins."
"Well, quite a stash there. I know vitamins are really good for you, so I have those to back me up."
"Well, if there's a danger there, I mean, certainly vitamins are important. I mean, vitamins are essential for life. Vitamins help us convert food into energy, but it's possible to get too much of a good thing. This is a perfect example. This vitamin A says a thousand international units, but if you look on the side under supplement facts, it says you get three thousand three hundred and thirty-three percent of the recommended daily allowance."
"33 times the recommended daily allowance? Is there any evidence that that amount of vitamin E is actually dangerous?"
"Yes, study after study has shown that if you take excess vitamin E, that excess vitamin A—both of which are antioxidants—actually increase your risk of heart disease. You actually increase your risk of cancer. So when it says heart health on the front, that's really mislabeled."
"Is it okay to take a multivitamin to fill in the gap?"
"What you find is that those who take multivitamins are not any healthier than those who don't. Now, they're not any less healthy, so I don't think that multivitamins hurt you, but I'd certainly say there's no evidence that they help you. I suspect it just makes for a lot of expensive urine."
"In the United States, this is an unregulated industry, meaning a company that makes this is under no obligation to frankly support its claims or admit its harm. Really, ever since the mid-70s, the FDA has not been allowed to regulate this product. We went through this at our hospital when people would bring in vitamins, and then we called the company to see whether or not it was made under good manufacturing practices and whether what's on the labels is what's in the bottle, whether they have a so-called certificate of analysis, and we were really disappointed. Ninety percent of the companies that we called either didn't respond, and of the 10% that did respond, much of the time we found out that the label was misleading."
"Unlike the FDA, Health Canada does have the power to regulate the vitamin industry, but regulated or not, Offit still maintains that supplements aren't the way to go."
"Pills are not the way nature means us to take in vitamins."
"Is this something that you can show me?"
"Truth? Let's go take a look at left."
"Right, so let's take vitamin A, for example."
"All right, the kind of thing that you would get from carrots or tomatoes."
"Exactly, and vitamin A serves a lot of functions. It helps with growth and development, it helps with eyesight, it helps with the immune system, especially as it relates to getting better from a measles infection, which I think many people don't know."
"So what are those things called that are inside of the tomato?"
"Well, there's a bunch of stuff. There's fibers and there's phytochemicals, other enzymes and coenzymes, all of which enable vitamin A to be taken up by the body in the manner that it's supposed to be."
"Painful?"
"Let's take a look under this microscope."
"All right, getting vitamins from food means they come with other essential ingredients like citrus bioflavonoids, which may help with their absorption."
"All right, so you've convinced me it's better to get the vitamins from the natural source than from the pill form."
"At least have my vitamin water. I mean, it tastes really good."
"Vitamin water? Words that go about as well together as red meat water just doesn't sound right, does it?"
"Okay, fine."
Back in Washington, Bryce takes a break to ponder his next move and the fact that even the experts don't seem to agree on supplements. According to Paul Offit, you should avoid taking vitamin supplements, but I also know I'm pretty low on vitamin D. Maybe it's time to investigate that.
Bryce decides to tackle his vitamin D deficiency with a little winter tanning while waiting for Reinhold Veith, one of the world's leading experts on the sunshine vitamin.
"Hi, Bryce."
"Hey, doc, what are you up to?"
"Let's try to soak up some vitamin D."
"You know, it's a little late for that. There's just not enough UV in the sunshine to make vitamin D anymore. But one thing you should be aware of is that if your shadow is longer than your height, there's not enough ultraviolet light in the sunshine to make vitamin D."
Veith has spent a lifetime studying vitamin D and is an advocate for upping our daily dose.
"Could you explain for a layman like me the process in which vitamin D is created by the sun?"
"Your skin is a cholesterol-producing organ. The sun does something in your skin that your body can't do, and that is make vitamin D. Direct exposure to the sun's ultraviolet rays transforms those cholesterol molecules into vitamin D. The active form enters our blood as a hormone, and one of its key functions is to enhance the absorption of calcium, which is vital to building and maintaining our bones."
"I've heard we have different needs for vitamin D because of their skin color."
"If you look at the skin color of a human being, you can estimate the latitude from which their ancestors came. Dark skin is a natural sun protectant. Our species evolved to live in the tropics, and our skin color was appropriate for there. But as people migrated away from the tropics, northward or south, where there was less sunshine, less sunshine and dark skin meant less vitamin D. Societies now speculate that human skin got paler to ensure our survival."
"Low vitamin D increases the risk of problems happening. One of those risks is, of course, osteoporosis or rickets, which is associated with misshapen bones. For a girl, her pelvis becomes too narrow to deliver a baby the natural way, and in ancient times, she would have died in childbirth. So lighter skin evolved so that we could not develop there. It was selected for. It was as if nature was saying, 'Your skin is too dark for the region in which you're living. We'll find somebody else to survive there that has a lighter skin color.'"
"Fair skin is nearly six times more efficient at making vitamin D, while darker skin offers better sun protection near the equator. But if you move north, it could pose a risk."
"So if you have darker skin and you live in northern climates, you're probably going to be much more likely to be deficient in vitamin D?"
"Absolutely true, yeah. We've done studies of University of Toronto students. After studying a selection of diverse young adults, Reinhold and his team discovered that the darker the skin color, the more likely they'd be deficient in vitamin D. In fact, this study revealed that on average, darker-skinned people living in northern latitudes had 50% less vitamin D than the recommended amount in their blood. They actually need more sunshine to make the same amount of vitamin D."
"So should Canadians like me be completely okay when it comes to vitamin D?"
"You might be, but you might not. We don't know for sure. We don't know yet what exactly the optimal amount of vitamin D is, and the answer to the question may lie in a number of different kinds of research. So researchers around the world are studying vitamin D precisely because there are so many unknowns."
"And what they're learning is pretty revolutionary. Apparently, there's a scientist here in San Francisco who made a startling discovery: that vitamin D isn't just essential for the development of our bones, but for the development of our brains."
"That expert is trailblazing biochemist Rhonda Patrick."
"So what made you decide to get into vitamin D research?"
"The vitamin D actually controls one twenty-fourth of the human genome, which to me says it's pretty important."
"Huh, to me it says I really need the sun."
"Well, vitamin D is actually not just a vitamin; it's a steroid hormone that controls the expression of over 900 genes in the body. My team and I found that vitamin D actually activates this gene called tryptophan hydroxylase that converts tryptophan into serotonin."
"Okay, so what exactly does serotonin do?"
"Serotonin is a neurotransmitter. It regulates social behavior, so the way humans interact with each other. Just how important is serotonin? Well, scientists say it regulates our appetite and digestion, it affects our sleep patterns, it influences romantic desire, and it even balances mood. Serotonin during early brain development plays an important role in shaping the way the brain develops, the structure and the wiring of the neurons. Studies have shown in mice that when you disrupt serotonin synthesis in early development, the mice have characteristics similar to autism. Researchers have known for a while that low serotonin is a key characteristic of autism."
"So given the vital link between vitamin D and serotonin, does that mean that autistic kids are vitamin D deficient?"
"Patrick believes that might be true, but autism only affects a small percentage of the population. Do the rest of us have to worry about this link?"
"Well, serotonin is important for brain function in everyone, and this has been shown experimentally. You can actually take a person and deplete them of their tryptophan, which is the precursor to serotonin, and normal people become very impulsive. They get angry; their long-term decision-making shuts down. So we're talking about, you know, everyone. Vitamin D is pretty essential."
"Are people getting enough of it?"
"Most recent surveys have found that in the United States, 70% of the population is not getting enough vitamin D. Vitamin D is critical to make serotonin, and serotonin makes you feel good. Given our long, dark winters, Canadians have an even higher risk for vitamin D deficiency."
"If skin color and geography can influence our need for vitamin D, then it obviously isn't as simple as take supplements or don't take them. Figuring out exactly what we need in terms of vitamins shouldn't be rocket science, right? Or is it?"
"So what do the big brains at NASA give their spacefaring astronauts to keep them healthy? To sort out the supplement confusion once and for all, Bryce takes off to NASA's Johnson Space Center in Houston to talk to the scientists who customize nutrition for astronauts."
"Astronauts are kind of the modern-day equivalent of seafaring old-world pirates. If anybody's going to know what we should be putting into our bodies to prevent scurvy and stay healthy in the long term, it's the brilliant minds of NASA."
Bryce has tracked down one of those brilliant minds, NASA's lead nutritionist Scott Smith.
"I'm responsible for the group that is involved with trying to keep astronauts healthy from a nutrition perspective, and in a sentence, we're trying to determine the nutritional requirements for long-duration spaceflight. Becoming deficient in almost any nutrient that your body requires sooner or later has very, very negative consequences."
"Like pirates getting scurvy?"
"Like pirates getting scurvy, exactly. From Columbus's voyage to the invention of the steam engine, there's about a 400-year period. It's estimated more than 2 million sailors died of scurvy. Ocean-faring explorers like this sea captain had to get all their vitamins from the food they brought on board ship, putting them at huge risk for vitamin deficiency. Astronauts in space for months face similar risks."
"When we have people flying in space on a limited food system, your risk of nutritional deficiencies goes up significantly."
"So before you send an astronaut up, what kind of work will you do to investigate their health profiles?"
"We do a detailed nutritional assessment in the crews before and after flight. We'll collect blood samples, we'll collect urine samples, and we'll measure 40 to 50 different chemicals in blood and urine samples to look at vitamins, minerals, bone markers, oxygen damage markers, proteins—you name it."
NASA advises its astronauts on adequate nutrition levels before launch, but is the food they take into space sufficient to maintain those levels?
"We provide the same food for everybody. We maintain that the space foods that are provided for the crews will meet all their nutritional requirements."
"Ensuring they get all their vitamins in zero gravity must be painstaking. I wonder what they do to all the food and how it tastes."
Bryce gets the scoop on that from Kimberly Glose, manager of the flight food program for astronauts.
"Can we—how does space food differ from traditional food?"
"Well, the interesting thing is that it doesn't differ from traditional food, and we're very proud of that. It's our goal to provide the astronauts with food products that they're accustomed to seeing and that they're accustomed to eating. For example, we utilize a lot of commercial products right from the grocery store in their own packaging. We simply put our label on it and a bell coin on the back so that the crew members can control the product in microgravity."
"Right, we want the food to be as home-like for the crew members as possible and want them to be products that the crew members are used to consuming."
"Okay, so I would be curious to try some of this stuff."
"Okay, let's go on. So first and foremost, we have a package of orange mango drink."
"So interestingly enough, we still use Tang."
"What we like to think of it as—rehydrated eggs don't taste half bad."
"But it does beg the question: does NASA mandate that astronauts take any supplements?"
"The only nutrient that we need to supplement with is vitamin D because the spacecraft are shielded, so the crews are not exposed to ultraviolet light. NASA doesn't require any other supplements."
"That's correct. There are some that like to take vitamins; there are some that hate taking pills, which usually boils down to, you know, like, if you want to take this, you're welcome to. We don't think it's going to help you; we don't think it's going to hurt you."
"What would you recommend for the average consumer?"
"What we recommend to crews is essentially what your mother told you: more fruits and vegetables, everything in moderation. I tell folks all the time, there's really no magic food. It really is getting back to the issue of the balanced diet. In a sense, we don't have to overthink it; just eat a balanced diet, and you'll get everything you need."
"That's correct. There's painful—is it sometimes? Is your mother was probably right?"
"We may not have NASA scientists monitoring and customizing our diets to ensure we get enough vitamins, but it doesn't need to be that complicated. If NASA says all you need is a balanced diet to get your vitamins, should we abandon supplements altogether?"
"The truth is, when it comes to vitamins, there are still so many unknowns. So does that mean we should overcompensate with a suitcase full of supplements or negative therapies?"
"I am myself going to avoid the trendy stuff because, from my experience, there just isn't enough science to back it up."
"So what's my nutrition plan moving forward?"
"I'll stick to a diet rich in colorful fruits and veggies, and I'll take a vitamin D supplement because I'm a little low. But a balanced diet is still the best way to get your vitamins. It's what mom recommended and what mother nature intended."
Next time on The Nature of Things: microbes. Well, actually crucial, and what makes someone clean or not is how we search into your gut. It's revolutionizing our understanding of health while we're living. Really, it's mind-blowing. The Nature of Things, next Thursday on CBC.
Way outside the box to where the magic happens: creating art in real games. A new series this fall, Friday at 8:30 on CBC.