
"Vitamin C is a water soluble vitamin. It's also sometimes referred to as ascorbic acid. So you may see that on ingredient labels and just know that that's vitamin C. It is crucial for the production of collagen and neurotransmitters and it's also involved in protein metabolism." - Amanda Izquierdo, MPH, RD, LDN
Shireen: Amanda is here though is a Chicago based dietitian and food and nutrition consultant. She has spent her career working with food, beverage and ingredient companies and marketing and public relations agencies to help brands effectively and credibly communicate their nutrition stories. She also works virtually with busy people to eliminate confusion around healthy eating, and build confidence about their food choices. Welcome, Amanda.
Amanda: Thanks, Sherry. And I'm so happy to be here.
Shireen: Glad to have you on. So Amanda diving right in. What led you to dietetics and really this career in weight management and behavior modification?
Amanda: Yeah, so my career actually started in pharmaceutical advertising and after a few years, I realized I hadn't yet found my niche or my passion. And I'm really a curious person, I always loved being a student. And over the years, I realized how much I also love teaching what I learned and dietetics is really based in teaching others. So I went back to school to earn my Master's in Public Health and Nutritional Sciences at the University of Michigan. And then after earning my credentials, as a dietitian, I knew I wanted to work in somewhat of a non-traditional role, so not necessarily at a hospital, which many people think of when they think of dieticians in the workplace. So I decided to use my experience in marketing and communications, with my knowledge of nutrition, to work in a way where I could communicate to the public about food and nutrition. There is so much confusion and misinformation about what to eat and what not to eat. So my mission is to put as much factual information out there when it comes to nutrition and I do this by, as you said, working with food, beverage and ingredient companies. But I also do this through my own content as well.
Shireen: Interesting. And so when you're talking about, you know, all the kinds of information that's out there, and how confusing it can get, one of my biggest ones is really understanding vitamins. I mean, it's so simple, and yet it seems a little overwhelming. What are the different categories of vitamins? And really, what, what is the difference?
Amanda: Yes. So to your point, they, it is somewhat so simple and when we think about vitamins, there really are only two categories. So we have either fat soluble or water soluble vitamins and when we say soluble, what that really just means is dissolve. So first, we'll talk about fat soluble vitamins. In order to absorb those by our body. They first must be dissolved in fats or oils, which our bodies do naturally during digestion, so they are often stored in our bodies, fatty tissue like our liver. And because they're stored, they can build up over time and high levels may cause some toxicity. On the other hand, water soluble vitamins are you guessed it dissolved in water before we can absorb them and then that means that they're typically eliminated much more quickly than fat soluble vitamins. So because of this, we really need to try and get water soluble vitamins consistently. Also, because water soluble vitamins are more likely than fat soluble vitamins to be destroyed or during normal food storage and preparation.
Shireen: And so what are examples of water and fat soluble vitamins?
Amanda: Yep, so fat soluble there's four of them vitamins A, D, E, and K. When I was studying nutrition, I always thought of them as a DAC. Another kind of mnemonic “Is all dogs eat kibble.” That's how you can remember all the fat soluble vitamins. And then when we talk about water soluble vitamins, those include vitamin C, and vitamin B, which is actually a complex of eight different B vitamins.
Shireen: Okay, so let's let's dive a little deeper. So let's start with the B vitamins first. What are they and where are they found?
Amanda: Yes, so B vitamins are found in a variety of foods and the good news is that deficiency is very rare. The most B B vitamins act as what we call coenzymes, which means they are essential for thousands of reactions that take place in our body every day and that's what makes them so crucial. So to start by, all of the B vitamins have a number associated with them. We typically call them by a more formal name, so for example, vitamin B one is also known as thiamin. Thiamin plays a critical role in energy metabolism, making it crucial for growth, development and self function. It's found in whole grains, meat and fish, and its most common source in the US is bread and cereal, which is often fortified with vitamin, vitamin B and is also known as riboflavin. riboflavin is essential for energy production, cell function, and the metabolism of fats, drugs and steroids. The thing about riboflavin that's interesting is it becomes inactive when exposed to UV light and since milk is a main source of riboflavin, it's why we've generally moved away from storing milk and glass containers because it's a way that the riboflavin is degraded. Eggs and beef liver are also good sources of riboflavin and again, like firemon many cereals and oats are also fortified with riboflavin. I'll move on to vitamin d3 which is also known as niacin. Once absorbed by our bodies, we convert niacin to us and what we call redox reactions in the body. So that means niacin is critical for either breaking down carbs, fats and proteins to ATP or energy, or it's used to build cholesterol and fatty acids that we need in our body. We do need cholesterol so it's used for both of those chicken marinara sauce, salmon, tuna, rice, peanuts, all sources of niacin and we can actually make niacin in our bodies from tryptophan which is an amino acid. Most typically associated with turkey. Vitamin B five is also known as pantothenic acid. pantothenic acid is essential for making and breaking down fatty acids in our bodies. Again, it's found in a variety of sources, cereal, shirataki, mushrooms and sunflower seeds. And then vitamin B six is typically one we call vitamin B six, but it's also known as pyridoxine. This vitamin is extremely versatile, and it's involved in over 100 reactions in our body, mostly due to protein metabolism. It's found in chickpeas, tuna, salmon, potatoes, and banana and vitamin B seven is also known as bieten and it is critical for fat, carb carbohydrate and protein metabolism. And it's also important in self signaling and gene regulation. Again, beef liver, egg, salmon, pork chops, sunflower seeds, sweet potato are all good sources. So as you kind of see, there's a lot of sources of all of these vitamins so it is easy to get them throughout the diet. The last two, folate or folic acid, also known as vitamin B nine, is essential for neural tube development. So it's really vital before and during pregnancy. Fruits and vegetables as well as fortified grains are good sources. To give you kind of an idea of how much you need. The recommended amount for adults is 400 micrograms and a one half a half cup of cooked spinach has 131 micrograms full eight. So just put it in perspective of how much you need. And again, folic acid is the synthetic version of fully and it's just as effective as the naturally naturally found folding. And then finally, vitamin B 12 is cobalamin. This is primarily found in animal foods, so things like cheese, yogurt, meat and eggs, but many grains and cereals are also fortified with B 12. Because of this vegetarians and vegans sometimes need to consider supplementing with B 12. Specifically, since they may not be eating those animal products and a deficiency might occur, and a deficiency can cause anemia, since vitamin B 12 is important in red blood cell development. And then again, just for reference, I find it helpful that the recommended amount of vitamin B 12. Every day, it's 2.4 micrograms, and a can of tuna has 2.5 micrograms. So you're already getting that, that amount. So really, all of these have varying roles. But all eight of them are very important for your body's energy and metabolism, really helping you to convert food into energy. Again, like I said, b 12, helps your body make red blood cells. niacin can help with normal nervous system function and then riboflavin keeps your skin and eyes healthy as well.
Shireen: Hmm, interesting. And then, when we're talking about, specifically vitamin supplements, do vitamin D supplements, are they just as good as the original sources that you mentioned?
Amanda: So they can be, but they're rarely necessary for most people. And that's really what I like to discuss. Again, as you heard some of the examples of where B vitamins are found. They're found in so many foods, so it really is possible to get enough from food alone. And as you heard to with the can of tuna example, you're meeting b 12. Already, tonight, something you eat. A lot of these B vitamins are really small doses that we need every day. So again, it is possible to get a B vitamins from food alone. I will say like, like I mentioned, vegans and vegetarians often do need b 12. Since the best sources are animal based foods, and again, in terms of B 12. Metformin can also reduce the absorption of B 12. So those taking Metformin may want to get their levels tested to understand if they also need a supplement. And then the only other one full eight, requirements increase 150% during pregnancy and lactation. So that's often a good one to supplement with as well. But again, as I said, the doses we need of some of these are so small. So for example, on pantothenic acid, the recommended amount adults need is five micrograms. And most multivitamins have 10 milligrams. So you're just getting huge doses and as we said, because we can't store them, we end up just excluding them, treating them very quickly.
Shireen: You know, one of the ones that, that stood out to me the B vitamins was biotin, because that's something that we hear about for hair, skin nails, you know, for growth of that. And so then can we, can we put maybe that mystery to rest to ask that are vitamin supplements needed? Or is it, is there plenty in the foods that you consume, so you don't need to, you know, necessarily have those supplements?
Amanda: Again, it is, it is found in a lot of foods, like I said, egg salmon, pork chops, sunflower seeds, sweet potatoes. You are probably getting it off and again, you can't store it. So it's really even if you have you know, you get 1,000% of bieten, you'll be just excluding most of that, because there was no place for it to go. I mean, there is I think we need some more research on if, if higher doses can, can actually help with hair and skin. There is some link to it, but again, you'll be reading in most of those mega doses out for sure.
Shireen: Interesting. Alright, so let's move on to vitamin C. So I think vitamin C immediately, my mind goes to oranges.
Amanda: Definitely.
Shireen: What is the importance of this white vitamin? And then where else is it found?
Amanda: Yes, so again, vitamin C is a water soluble vitamin. It's also sometimes referred to as ascorbic acid. So you may see that on ingredient labels and just know that that's vitamin C. It is crucial for the production of collagen and neurotransmitters and it's also involved in protein metabolism. When we talk about collagen, it isn't just for more youthful looking skin as we've all heard, I'm sure. Collagen plays a critical role in wound healing, so that's why one of the reasons why vitamin C is so, so critical. Vitamin C also acts as an antioxidant, which means it can limit the damaging effects of free radicals in our body. And as you mentioned, citrus oranges are probably the most well known food sources of vitamin C, but I always like to mention that bell peppers actually have more vitamin C per serving. Overall fruits and vegetables are going to be your best sources of vitamin C. Kiwis, strawberries and broccoli are also good sources. And again, for that reference point, the recommended daily amount of vitamin C for adults is 75 milligrams for women, and 10 milligrams for men. And three fourths cup of orange juice has 93 milligrams of vitamin C. So you're already meeting that just by having some orange juice in the morning.
Shireen: And so let's move on to supplements when it comes to vitamin C, would you recommend that?
Amanda: So honestly, no. Only if you're not eating any fruits or vegetables again, most people are able to get enough vitamin C from food alone. And deficiency of vitamin C, which is known as scurvy, is really, really rare today. It was predominantly something we saw in sailors when they were coming over long journeys on boats where they couldn't have any fresh fruits and vegetables, and so they developed scurvy. But we really don't see it anymore today and the reason why I don't recommend it is, again, we can't store vitamin C. So if you take mega doses, most of it won't have anywhere to go in your body. So what will end up in your urine, you're essentially just putting money down the drain. And that's, you know, I'm just trying to look out for your wallet it, it really, the research hasn't shown that mega doses can help delay colds. It really isn't, isn't able to do that. And so taking these mega doses, just really ends up being a straight from your body.
Shireen: And so what, one of the things that you mentioned with it being water soluble is like if there's, if you're having more than what your body can really consume at any given time, then it's really being excreted out. Which is such a shame, because especially if we're doing supplements, it's like, oh, you're just having it and then it's coming right out of you.
Amanda: Exactly. And, and the good thing is we find that with water soluble vitamins, there's less of a, less of a possibility that you'll, the toxic levels can be detrimental to your health. So with vitamin C, if you take huge doses, there really are limited negative effects. Probably the biggest effect is you might have some digestive issues, just some discomfort on, but it's not really harmful for you. So I think some people think that it's not harmful, I can, I can take as much as I want. But at the end of the day, it's just you're not really doing anything for yourself by taking these huge doses of vitamin C and B vitamins. Okay.
Shireen: And then is it better to, I guess, moderate water intake with this? So it's not getting flushed out? I mean, is there anything can we do to….?
Amanda: I wish but no, please don't please don't take your dog's drink. Again, it's these, these vitamins are found in so many foods we eat. So it is very rare to have deficiencies of them and need water. You need water for many different things. So continue to consume water. And again by eating a variety of foods throughout the day. Again, you might not get 100% of your needed vitamin C today, but you may get more tomorrow. So it's really not about what you're doing today, but over time that you're eating these foods regularly and getting most of these vitamins all the time.
Shireen: Alright, so with that, I mean we're toward the end of the episode. This was very intriguing. How can our listeners really connect with you and learn more about your work?
Amanda: Yes, so um, you can follow me on Instagram at Izzy, IZZY Eats RD or head to my website, www dot amanda excuse photo comm you can sign up for my email list, which I send out with resources, recipes and more fun food and nutrition tips.
Shireen: Love it. Well with that Amanda, thank you so much for making the time, for coming on the podcast, for enlightening us with vitamin B's and vitamin C's. I feel like we need to do a follow on with the fat soluble vitamins, but this was really refreshing to learn about the waters, with the water soluble ones. So I really thank you for your time.
Amanda: And thank you, pleasure to be here.