Friday, October 4, 2013

Should you cook your food?

I work with an advocate of a "raw food diet", and he has really been challenging my views and opinions on nutrition.  You may be asking yourself what a raw food diet is. It's typically a vegan diet (no meat, dairy, or eggs) in which food is minimally cook and/or processed.  I guess someone can be a raw food enthusiast and still eat meat, but that's not very safe.  I've read different statistics, but it sounds like cooked food takes up less than 50% of the what's eaten, and when it is cooked, it's at lower temperatures for short amounts time.

When man was first created, we didn't necessarily have the means to process or cook our foods.  So it got me thinking that maybe we were created to live off the land and not mess with it too much.

My question is:
Should we even be cooking our food at all?

The premises of  a raw food diet is that you choose foods that are higher in nutrients, and you maximize the vitamin and mineral content by not cooking/processing it.  There is another supposed benefit of natural plant enzymes, as well.

Cooking food does cause some vitamin and mineral losses, but it is not apocalyptic.  The water-soluble vitamins (B and C) tend to be the least stable, and many vitamins and minerals can leak out when they're boiled or when the food loses water (Leskova et al., 2006).

As for the plant enzymes, I am having a really hard time finding credible resources as to what those enzymes are and whether or not they can have health benefits.  The assumptions most people make is that if there are enzymes in our food, then they will be digested so it doesn't matter anyway.  I've heard some arguments to that assumption, but since I can't credit or discredit it at this time, I'll choose to ignore it.

Now, there are obvious health benefits to this diet because you will be removing junk  and including more fruits and veggies.  All junk food has been cooked or processed.  Because they are taking out the biggest sources of saturated fat and cholesterol, people on raw food diets tend to have lower LDL cholesterol and triglyceride levels (Koebnick, et al., 2005).  Additionally, high intakes of fruits and vegetables are usually associated with decreased risks for high blood pressure, stroke, type II diabetes, certain types of cancer, and obesity (Craig, 2010)

But we have to keep in mind that eliminating entire food groups can limit nutrients, so raw food diets and even vegan diets are typically not perfect.  For instance, when you take out the dairy group, most people don't get enough calcium.  Dairy is our highest source of calcium.  You can get it from other foods like green leafies and beans, but dairy and (dairy replacers for that matter) have the most calcium.  There has been research that shows that a raw food diet is associated with bone loss (Fontana, et al., 2005).

Also, when meat is restricted, vitamin B12 can be a worry.  Animal products are our biggest source of B12, so many vegetarians/vegans are at risk for B12 deficiency (Koebnick, et al., 2005).  So we worry about a restrictive diet in anyone, especially kids.  Because kids can be picky to begin with, we worry about limiting their available food further.  Statistically, it looks like vegetarian kids may have higher risks for deficiencies in vitamins B12 and D (Dwyer, et al., 1982).

But people can overdo just about anything.  Just like going crazy on the cooked Tastykakes, going crazy on fruits and veggies can sometimes be problematic.  One thing we worry about is the acidity of some fruits and veggies.  People on a raw food diet have a higher risk for dental erosion (Ganss, Schlechtriemen, & Klimek, 1998).  Crazy, huh?  The author of that paper attribute it to the high acidity of some fruits and veggies.  Some processed foods have acid controls (buffers) as additives to control acidity, but raw food doesn't really.

So because a raw food diet (which is usually vegan) is missing out on some important stuff, we can't really recommend it on a long-term basis without supplements. The biggest thing we see long-term is the risk of osteoporosis when calcium intake is not high enough (Appleby, et al., 2007).  Also, some people lose too much weight and actually become underweight, causing a whole mess of other health problems like losing your period (not in a good way) (Koebnick, et al., 1999).

It sounds like an optimal diet contains both cooked and raw foods. Because the raw foods tend to be fruits and vegetables, the health benefits are still seen.  Also, many cooked and processed foods may contain the nutrients that are missing in a raw vegan diet .  It looks like if someone wants to go raw, they should only do it for a short while and then go back to eating some cooked foods (Shetreat-Klein, 2010).

The good news is that there are some benefits to cooking your food.  One really good thing to note is that when you cook food, you kill bacteria, thus making animal products edible.  That means those pesky vitamins B12 and D are no longer a concern.  Killing bacteria makes the food last longer in the fridge, too.  Also, some antioxidants like carotenoids actually work better in your body when they've been heated (Boekel, et al., 2010).

The best way to minimize your losses in vegetables would be to not use direct heat, keep it at medium or lower settings, and don't cook it more than 10 minutes.  I always tell my students to strive for their vegetables to have the texture of Chinese food.  You know, it still has a little crunch to it.  So in theory, as long as you don't turn all of your food into mush, you're still going to have some nutritional value to it if you cook it.

So long (I know this one was long) story short:

Yes, it is perfectly acceptable to cook your food...especially ones that taste nasty raw like potatoes. 

And no, you cannot live off of cooked Twinkies your whole life and think you're going to be healthy.

Thursday, May 16, 2013

How Much Timber You Drop Off


Random thought:


As a dietitian, I sometimes have to talk about .... poop.

Now for some people, this may seem like an odd topic, but most medical professionals find themselves unmistakeably discussing defecation (the fancy word for pooping lol) from time to time, and in my family, this has always been an open topic.

The other day, my husband called me at work to ask me how much weight he could lose while releasing stool, so of course I had to research it.  Before I go any further, I already know we're weird lol.

So the questions of the day are:

How often do people go, what affects how much your poop weighs, and how much weight can you lose when you excrete it?

Surprisingly enough, there are some credible resources on the subject, but it seems poop wasn't popular after the 90's.

If you're one of those people that doesn't go every day, don't despair.  The reality is that most people don't go every day, and very few people go multiple times a day.  The norm is actually to be irregular.  (Heaton, et al., 1992) Crazy.

How much poop you make is dependent on what you eat.  This makes sense since that's what poop really is - the leftovers from your diet that didn't get digested.  The 2 big kickers we look at are fiber and water.  The more fiber you eat, the heavier your stools are.  Also, as fiber intake increases, frequency of elimination often does as well (Cummings and Stephen, 1980). 

We also look at water because soluble fiber binds to water adding weight to the stools.  Your poop is something like 75% water, so if you're dehydrated or if it's been in there a while, that's going to have an effect on the weight (Picco, 2012)

A study done in 1984 (I know it's old) showed that in a 24-hour period, people poop somewhere between 19 and 278 grams (Eastwood et al., 1984).  Relying on Google to do the conversion, that comes out to be between .04 and .61 pounds per day.  So in essence, you really could lose like a half pound of poop in a day, and if you were sick, I don't think it's unreasonable for you to lose a whole pound or so depending on how much was in there to begin with.

On a weird side note:
Did you know we probably don't poop right?  According to this study, people strain less when they squat than when they sit on a toilet.  My sister-in-law was right.  They do have it figured out in China.

Admit it. You were curious.

Wednesday, March 6, 2013

Cha-Cha-Cha Chia Diet

Random Thought:

My husband thinks it's funny when I get get angry at all the crazy tactics people use to try to get skinny. He finds humor in emailing me with the latest fad diets he reads about on yahoo.  His latest  message included a video about the "Aztec Diet".  So in honor of him, I will devote my latest post to this latest craze. 

Let's first start with answering the question "Who are the Aztecs?".  I'm not trying to say that I'm not cultured, but I will be the first to admit that I am not an expert in history or geography, so I had to do some research.  Because I am so bad with history, I found a super cute website made to teach little kids about the Aztecs.  Whatever...the information seems legit, and I can actually understand it.

So anyways, according to http://aztecs.mrdonn.org/,  the Aztecs were pretty innovative in their farming and marketplaces, and they were supposedly great warriors.  Ooh, and they were the ones that built those cool pyramid temple things in Mexico, but they are notorious for human sacrifices - ^creepy^.  They were for the most part a hard-core tribe in Mexico that dominated the Valley of Mexico...that is until the Spanish came in and killed them off with disease.

What's so cool about their diets?  I honestly don't think they were anything to get excited about, but this guy Dr. Bob Arnot thinks they're pretty special.  He's the one that developed the Aztec diet.  A big thing this diet focuses on is the chia seed..That's right; I said chia seed.  The very same seed you may have tried to grow in little orange animal-shaped pots.  I don't want to brag, but I had a Scooby Doo one, and it was pretty cool.

Dr. Bob claims that chia seeds were eaten by the Aztec people and that they are super healthy, and technically, he is not wrong.  Chia seeds are whole grains that do have protein, vitamins, minerals, and a good amount of fiber.  I think they even have heart-healthy omega-3 fatty acids, as well.  Now that's not the only thing people are supposed to eat.  If you read this website dedicated to the diet, http://www.aztecdiet.org/, you'll see that it is full of healthy choices like fruits and vegetables and lean meats and beans, as well.
  
So...does it work?  I was worried I wouldn't be able to find information since the book just came out in February.  Thankfully, another dietitian writing for WebMD has already done some research.  According to her article,  since chia is high in fiber, it should in theory work.  Fiber itself is pretty good at helping people achieve healthy weights because it takes longer to eat, it binds to water in your stomach making you feel full, and it delays gastric emptying which can make you feel full for longer.  Right now there is no conclusive data stating that chia seeds are amazing at helping with weight loss, though.

Let's be realistic here.  If you're now choosing fruits and vegetables and foods high in fiber instead of your usual crappy diet, it makes sense that you could lose weight, with or without your chia pet.  So in essence my opinion on weight loss hasn't changed.  Let's not waste our money on crazy diets, and let's start eating healthy.  Healthy foods tend to be low in Calories.  When you eat less Calories than your body needs, eventually you will lose weight - plain and simple.

On a side note, this Dr. Bob is the host of "Dr. Danger", a travel show where he has adventures in Africa and the Middle East. 

How does traveling to Africa make you an expert in an ancient Mexican tribe?  It doesn't.  He supposedly has a medical degree in addition to being a television star and has participated in research with other healthy diets.

How does being a physician on TV make you an expert in healthy diets? It doesn't.  Even though he may have once participated in research, I think once you sell out with a crazy diet plan then you lose all credibility in my book.

Sunday, January 13, 2013

Don't Feed Your Zits

Random Thought:

I have had acne since I was in high school.  It escalated on my forehead my senior year, slowed down in college slightly, then went crazy on my chin and cheeks when I moved to Virginia.  I have heard tons of theories about how chocolate and greasy food can cause acne, and as a dietitian, I am extremely interested to see if there's anything I can change in my diet to reduce the amount of pus-filled, tumor-like, painful, red growths that plague my face...

Maybe I'm exaggerating the severity of my condition, but as a professor, I have 8-classes worth of eyes on me.  I already look young, so the acne definitely doesn't help.

So I want to find out whether there's anything I can change in my diet to lessen my pimples.

Let's start off by defining what acne really is.  Those nasty heads develop when too much sebum (oil) is made, causing the hair follicle cells to produce rapidly.  If it doesn't close off, it's a blackhead; if it's closed, it's a whitehead.  Acne tends to run in families, but it has to have an environmental trigger, like maybe food, in order for it to be expressed (Spencer et al., 2009).  Let's look at some foods to see if there are any connections.

Chocolate: Contrary to popular belief, there is no connection between chocolate intake and acne (Spencer, Ferdowsian, & Barnard, 2009).  Doesn't matter if it's dark or milk, I've read a few articles that say chocolate doesn't cause zits.  Thank goodness.

Milk:  I was very surprised to read that dairy may increase acne.  People that have higher consumption of dairy foods have higher risks, and populations that have lower intakes have lower prevalence of acne (Bowe, Joshi, & Shalita, 2010).  I'm not saying to exclude this food group, but if you have acne problems like me, it may be better to choose dairy replacements like soy milk. 

Grease: Studies suggest that some types of fats may worsen acne and others may make it better.  For instance omega-6 fatty acids and saturated fats may increase inflammatory acne, and omega-3 fats may reduce it (Spencer, Ferdowsian, & Barnard, 2009, 2009).  It makes sense since omega-6's are pro-inflammatory and omega-3's are less inflammatory.  Omega-6 fatty acids can be found in vegetable oils like sunflower, safflower and corn oil, and omega-3 fatty acids can be found in fish, canola oil, and nuts (Franzen-Castle & Ritter-Gooder, 2010).  Saturated fats are associated with animal products. So avoid salad dressing, Fritos, eggs, milk, and meat, and bring on the seafood and nuts. 

Carbs: Just like fats, some carbohydrates have been shown to not be good for our faces. High-glycemic index (GI) foods may contribute to pimples (Bowe, Joshi, & Shalita, 2010).  The glycemic index refers to a number that is delegated to food based on how your blood sugar rises after to you eat it, how quickly it gets there, and how long it takes to get it back down.  High GI foods tend to be made with sugar and white flour.  Click here for more descriptions.


We have to keep perspective here.  Diet is not the only environmental factor that can cause pimples, but I am interested to see if I could see any changes in my face if I reduce my intake of animal products and refined carbs.  My New Year's resolution was to see a dermatologist, and I will definitely be bringing this up to him/her.

References:
Bowe, WP, Joshi, SS, and Shalita, AR. (2010). Diet and acne. Journal of the American Academy of Dermatology, 63 (1), 124-141.

Franzen-Castle, LD and Ritter-Gooder, P. (Aug. 2010). Omega-3 and omega-6 fatty acids. Retrieved from http://elkhorn.unl.edu/epublic/live/g2032/build/g2032.pdf

Spencer, EH, Ferdowsian, HR, and Barnard, ND. (2009). Diet and acne: a review of the evidence. International Journal of Dermatology, 48, 339-347.