How to Read the Research Yourself

There are so many different places to get information on health, nutrition, child development, and parenting: the news, magazines, websites, blogs, your pediatrician  your mother-in-law. It can be overwhelming to sort out the facts and decided what to do for your children. Good sources at least tell you where they got their information (who is Dr. KnowItAll anyhow?); better sources cite specific studies (are they quality studies?); the best sources are peer-reviewed scientific articles. Unfortunately, these articles can be hard to access, and even harder to understand. It is my hope that this guide will introduce you to the world of research and give you some basic tools so you can go straight to the source, finding the best information for your family.

So why bother reading the study instead of the news article? Newspapers are trying to get your attention, so they often take parts of a study and write a catchy headline that can be misleading. Here’s an example: “ A cheese sandwich is all you need for strong decision making”. The actual articles is “Serotonin modulates behavioral reactions to unfairness” and the researchers didn’t even mention cheese. What they did do was give subjects a drink that affected their serotonin levels indirectly through tryptophan, then presented them with a situation where they were treated unfairly and recorded the tendency to take revenge. It so happens that cheese and chocolate contain tryptophan too, but it’s a big jump to go from an artificial tryptophan cocktail to a cheese sandwich, and from a controlled test on unfairness and revenge to “strong decision making”, whatever that means. While it’s not the easiest way to get information, reading the study itself is the most reliable way. (http://www.ted.com/talks/molly_crockett_beware_neuro_bunk.html?quote=1993. http://www.sciencemag.org/content/320/5884/1739.short)

I would like to present you with some tools to help make accessing the studies easier. First, we will talk about places to find studies to read. Second, we will go through some different types of studies you might find. Next, we will go through some of the roadblocks to understanding you may encounter. Finally, we will take everything we have learned and evaluate studies to make decisions applicable to our lives.

The easiest tool for the home investigator like yourself is probably Google Scholar. It is a free search engine that contains scholarly articles, many of which are free to read. Others may only give an abstract or summary, so you can get the gist without any of the details. If you want more details you can purchase the article, but that is quite expensive. Many college and university libraries already subscribe to the most reputable science journals and may offer free services to the public, so check their periodicals section first. I have even heard of large public libraries offering this service as well.

So now that you have started looking for papers, let’s talk about some different types of studies you will find. When we are talking about medical studies, such as you will find when you look for information on disease and nutrition, you will find three basic types: in vitro, animal, and clinical. In vitro tests take tissue from people or animals, and test them in a lab to see how they react to different treatments or exposures. Animal tests, you guessed it, are done on animals, and are usually the result of a promising in vitro test done earlier.  The advantage to animal tests is that the effect the researchers are testing can be seen in a whole organism  not just small groups of isolated cells as in an in vitro test. If the animal tests go well, scientists move on to clinical tests where volunteers are subjected to certain treatment and the results are reported. Clinical tests are the most applicable to our lives, and there is danger in jumping to conclusions from in vitro or animal tests although they are very important steps in the process. Clinical tests may be blind tests, where the subjects don’t know what treatment they are receiving, or double blind, where neither the subjects nor the administrators of the test know.

Of course, not all studies are strictly biological. Studies of behavior usually fall into three categories: cross-sectional, retrospective, and prospective.  Cross-sectional studies are surveys about present factors and conditions that try to find relationships. (For example, how tall are you, and do you have blonde hair? might show that blondes are taller than brunettes) These are fairly easy studies to conduct and a great starting point for research, but it only shows correlations, not causes. A good quality cross-sectional study can still make really good guesses about causes though by doing some fancy statistics to weed out already known causes. Retrospective studies are a better look into causation because they ask people about past behavior and compare it to their current condition. One problem with these is that they rely on people’s memory and honesty. The best, and most time consuming and expensive, studies are prospective because they take a group of people and track them into the future.

Once you have an idea what kind of study you are looking at you start reading, and maybe it is getting complicated and overwhelming fast. You do need to have some background knowledge as you attack the literature. Check out my list of recommended books for basic information on subjects in which you are particularly interested. For more specific questions, I have found Wikipedia to be a great resource. While anyone can write a Wikipedia article, the more common articles are quite accurate thanks to that very fact. Mistakes get taken out so quickly because anyone can correct them.

The next challenge is probably all the statistics. I want all of you math-phobes to take a big deep breath; it isn’t going to be too bad. Here’s what we are covering today: confidence intervals, distributions, and significant results. There is off course a lot more to learn about statistics, but those three things should get you started.

First: confidence intervals. We can never include 100% of the population in a study, so we take a sample, maybe 300 people. We then try to take what we learned about those 300 people and generalize it to the population in question. A confidence interval tells you how sure we are that our results (the sample) match reality (the population) within a certain range. In the literature it will say something like, +/- 3 grams, 95% confidence interval, meaning that we are 95% sure that we have the “right answer” within 3 grams. The thing to look for with confidence intervals is to look at the extremes. If the bottom of the interval is in the negatives, you might question the results. For example, they may say eating eating a certain food has a positive average effect within a certain interval,  but the bottom of that interval is actually a negative effect, so there is a chance that this food is actually bad for you! That’s why we never just look at an average.

Averages are also misleading when there is a wide distribution of results, meaning that a variable had much more affect on some people than others. You may be familiar with “the bell curve” or a normal distribution. This is where the vast majority of results are right around the average, and the further away from the average, the fewer data points there are.  If we graphed it with results along the bottom, and number of people  who got those results along the side, it looks like a bell. When studies look like this, they are easy to interpret, but that’s not always how things fall. Always pay attention to the distribution curve when it is provided in a study. If the graph has a long tail to the right, than the average will be pulled to the right, and most people/results will be less than “average”, and visa-versa for a long tail to the left. You may also see two humps, meaning that there were two common results. In that case, the average is probably between the two most common results, even though that is a low point on the graph: perhaps there isn’t a single data point at the average!

Another problem with not being about to study a whole population is that when we do find that a variable has an affect on the results we must make sure that we didn’t just get lucky. For example, say we are trying to see if 3-spotted ladybugs like water more than 4-spotted ladybugs so we go to the pond and the forest and collect five lady bugs at each site. We count the spots and find that all the ladybugs at the pond have 3 spots, and only three of the five from the forest had 3 spots. We must ask: what if we just happened to pick up the only 5 three-spotted ladybugs at the pond, and the other 50 bugs we didn’t catch all have 4-spots, and we just happened to find fewer three-spotted ladybugs in the forest even though they are much more common there? If that is the case, then our study would draw the wrong conclusion. This is what they are taking about when they say there is a “significant difference”. It doesn’t mean the difference is large, simply that considering the sample size compared to the population, and considering the difference they did find, they are reasonably sure that it is not just luck, there is a really correlation here. There is a mathematical formula to decide if a result qualifies as “significant”, but it can be a little misleading because the larger the sample, the smaller the difference needs to be before it is “significant” so check that before you base major life changes on the study. If the study included a huge number of people, the “significant” result could be tiny and perhaps not worth turning your life upside down. (Statistics for Engineers and Scientists by William Navidi)

Okay, so we have gone through how to get your hands on some scholarly papers, and how to make sense of them. Now it’s time to decide what we think. Evaluating the quality of a study is mostly about common sense. Look for anything in the methodology that might introduce bias, such as it not being a double blind study, or perhaps the sample is not representative of the population. Do a search of other papers that reference this one. Have the results been replicated? criticized? or disproven elsewhere? In the end, it is up to you to decide how this research affects you and your family.

Happy Digging!

 

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Why Juice is a “No-No” in Our Family: Part 1

This is marketed to babies?! (By the end of the post you will be thinking this, trust me)

There was a time, in the very recent past, that I was proud to feed my toddler 100% fruit juice. It is all-natural, has no added sugars, and is rich in vitamin C! What could be better? Admit it, you have thought this yourself, but today that ends. There are a few different reasons why there is more to juice than meets the nutrition facts label, so I decided to divide this post into parts so I can fully convince you on each without having to rush over details. Today’s post is all about fructose’s link to metabolic disease.

All carbohydrates are chains of sugars: fructose, glucose, and galactose. What we call sugar is a single molecule of one of these, or two bonded together. Sucrose for example (table sugar) is a fructose molecule bonded with a glucose. Corn syrup is also a combination of fructose and glucose, the only difference being they are not bonded together. This isn’t a big deal because our bodies can easily break that bond making corn sugar and cane sugar equally bad for you, along with other “natural” sugar such as fruit juice,  molasses, agave, maple syrup, honey, etc (although these may have some good stuff in addition to sugar, the sugar is still bad) Starches, what most “carbs” in our food are, are long chains of glucose which are also easily broken into single glucose molecules. Glucose is the only thing cells can use for energy, so glucose is good, of course unless we have too much and it is converted to excess fat. It is the fructose that makes sugar different from other carbohydrates.

The difference between glucose and fructose

Your body breaks up carbohydrates into their constituents and empties them into the blood stream. In the case of glucose, the pancreas then secretes insulin, which allows tissues to absorb it for energy and triggers leptin, the chemical that tells your brain to be satisfied. This is good. About 20% of the glucose ends up in the liver where it is stored as glycogen which is used for energy. (This is what “carb loading” athletes are doing) A very small amount escapes the glycogen process and goes through the citrate process which creates VLDL (really bad cholesterol). All in all, our bodies handle glucose very well. Fructose metabolism is very different. Remember that cells can only use glucose, so when you eat fructose, all of it goes straight to the liver. Glycogen, that safe non-fat energy storage system of the liver, is made from glucose, not fructose, so it doesn’t end up there either. It can only end up as: fat, VLDL, and uric acid. All three are really bad for you.

Result: Metabolic syndrome

Fat is the ultimate destination for 30% of the fructose! I don’t have to tell you that excess fat is bad and linked to obesity, but there is a second way that fructose increases your risk for obesity. (This part is pretty complicated, so while I apologize to you biochemists out there, this blog is for everyday parents so I am simplifying) Fructose increases insulin but makes in ineffective (particularly in the liver). All of that insulin makes fat cells more able to store glucose as fat, makes the pancreas work really hard to produce all that insulin, raises your blood pressure, and confuses your brain so that it can’t sense leptin (remember leptin is what makes you feel satisfied) . That means if you give a kid a juice or a soda pop with his meal, he will eat more, even though he is getting extra calories from the drink on top of the now extra large meal. This at lease one reason why fructose, especially in sugary drinks,  has been strongly linked to obesity. (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2673878/, http://ajcn.nutrition.org/content/79/4/537.shorthttp://jcem.endojournals.org/content/89/6/2963.short)

VLDL is very low density lipoprotein. It is the worst type of LDL, the “bad” cholesterol, because it is the most likely to cause plaque build up in your blood vessels, leading to coronary heart disease (CHD). CHD is the number one killer in the US, and unfortunately we are starting to see children with cholesterol problems. In fact, the American Academy of Pediatrics recommends that all children start getting tested at 3 years old! (healthychildren.org, a website by the AAP and cdc.gov)

The last place fructose can end up is as uric acid. You may recognize uric acid as the culprit behind gout. This is true, but it also has the effect of raising blood pressure. This is in addition to the blood pressure raising affect that fructose has through insulin discussed above. High blood pressure puts undue strain on the arteries and on the heart and is a risk factor for developing type 2 diabetes. (MayoClinic.com) What do you call the combination of obesity, CHD, and type 2 diabeties? Metabolic syndrome. That’s right. Fruit drinks are very clearly linked to metabolic disease as shown in this 2010 meta analysis that included well over 300,000 participants (http://care.diabetesjournals.org/content/33/11/2477.short).Let me say that again: regular servings of fruit juice can lead to metabolic syndrome, and no one wants that for their children.

Okay, okay. Sugar is bad, but we are talking about FRUIT! All-natural fruit!

No, we aren’t talking about fruit. We are talking about juice, the sugar water extracted from fruit through processing. Fruit comes with fiber. Juice doesn’t, and that is a very important distinction. Fiber, particularly the combination of soluble and insoluble fiber (note that “added fiber” is only soluble), prevents sugar from being absorbed in the intestines. That means that as far as your body is concerned, an orange has less sugar (and calories by the way) if you eat it as an orange than if you squeeze it into fresh orange juice. Keep the pulp? That might be better because it will be more filling in your stomach, but you still lost the fiber in the section membranes. Put the whole thing in the blender and make a smoothie? Even better, but the blender does damage  the insoluble fiber and remember that it is the combination of soluble and insoluble fiber that prevents sugar absorption. Nothing can match the whole fruit, the way nature created it.

So next time you or your family is craving fruit juice, break out the whole fruit. You can get the nutrients and sweet taste without the damaging affects of the sugar. I think the diet industry would call that a miracle, but nature is full of miracles.I hope by now you are convinced that putting fruit juice in your kid’s sippy cup is no better than giving them ice cream  for lunch.  If you aren’t convinced yet, here is a really great lecture by Dr. Lustig, a Pediatric Endocrinologist at UCSF: https://www.youtube.com/watch?v=dBnniua6-oM. He cites lots of studies that I left out (because I honestly was a little overwhelmed by the massive number of supportive studies and just couldn’t fit them all into one blog post) It is an hour and a half, but if you don’t have that kind of time, here are the slides http://xa.yimg.com/kq/groups/17487767/1011600327/name/Lustig+Sugar.pdf. If you are more of a reader than a watcher, here is an overview of the research (over 79 studies cited) by Alan R. Gaby, MD: http://www.anaturalhealingcenter.com/documents/Thorne/articles/fructose10-4.pdf

What this looks like in our family

Well, our little boy is still breastfeeding, so that takes care of some of his liquid needs, but during the day his sippy cup is filled with water. It is as simple as that. We do give him whole milk sometimes (I am still not sure how I feel about milk, but that is another post for another day). Now my husband has been a hard one to get on board with this, so there are many nights that he whips up a smoothie and J is able to put on his cute face and get a few sips of Daddy’s juice. My point: we are far from perfect, but this blog is about being “slightly better” each day, not perfect right away.

I think the most important thing is to simply recognize that fruit juice is a “sweet”, not a health food. Once I had that switched in my mind, it was just as easy (okay, hard) to limit juice as it is to limit brownies. (I am sitting here now picturing gooey yummy brownies…. and now you are too. Sorry!) I hope I have at least started to convince you to limit sugary treats, even fruit juice. Let me know how successful I was by commenting!

Why Sportscasters Make Great Parents

“He has the ball and is quickly heading for center field .. and he fumbles! Wait no, J recovers the ball is is off again. There’s some trouble up ahead but J maneuvers to the right, avoiding being tackled by the swing set  He might go… all… the.. .way! Touchdown! The game is over! J celebrates by going to play with the toy cars on the porch.” Does that sound familiar to anyone? Okay, so you probably didn’t say exactly that, but studies show that it may not be a bad idea.

In fact, it is a very good idea to narrate life for your children. A study by Betty Hart and Tood R. Risley entitled “Meaningful Differences in the Everyday Experiences of Young American Children and Learning to Talk” found the number and variety of words that children hear throughout the day had an overwhelming impact on the child’s own vocabulary. The study included 42 children age 7-8 months, and followed them through to their third birthday. Every week, the researchers would go into their homes and record every word spoken, and every interaction the child heard, experienced, or said themselves. They were hoping to learn why some children have larger vocabularies when they beginning preschool at age 4, and why their intensive intervention programs to help under-performing children made little difference long term.

What they found was astonishing. The children that had the largest vocabularies heard three times as many words as those that lived in more “taciturn” families, had their actions affirmed 8 times more (and discouraged far less as well), and were given ten times more opportunities to join the conversation themselves. Extrapolation this data amounts to a 30 million word difference in only 3 years; it’s easy to see why later interventions can’t catch these children up.

That is just what a later study by Dale Walker found. He was able to meet up with most of these children in fifth grade and test them again. He found that the children with smaller vocabularies at age 3 were still behind at age 10. In fact, their test scores didn’t correlate directly with their elementary school experience at all. (“Prediction of School Outcomes Based on Early Language Production and Socioeconomic Factors” by Dale Walker*, Charles Greenwood, Betty Hart, Judith Carta) It makes sense because these same children were in the same family environments, whether they are linguistically rich or poor, and the original study by Hart and Risley found that parents didn’t increase the amount of child directed speech as the child got older; if they talked to the child a lot during infancy, they continued through out childhood and visa versa. I will throw in this however: parents who talked more tended to be in a higher socio-economic group and had a larger vocabulary themselves. The study clearly indicated that the increase in child vocabulary was not caused by the social class, but was less clear about the affect of a parent with a larger vocabulary. The children with the largest vocabularies at age three had larger vocabularies than the parents of the poorer performing children, so it is logical that children will not learn words their parents do not know. The bottom line: Parents are the most important educators in a child’s life. (But we already knew that, right?)

So how can we apply this as parents? 

Talk! It really is that simple. The researchers found that by simply talking more, parents automatically are using richer language. When I had my son J, I had heard of people talking to their newborns, but it sounded so silly to me. Since it was just J and I home all day, our house was really quiet. In fact, taking him to family’s houses sometimes scared him because so many people were talking and laughing. I often wonder if my quietness lead to his late speech, but I can’t go back and change that now. I just decided that I would change today and start making up for “lost words”.

It was HARD. Surprisingly hard. I am a day dreamer, and it really took my concentration to mentally stay with my son and speak to him more. I found that pretending to be a sportscaster really did help. I told him what he was doing, described the world around us, and gave him plenty of opportunities to respond, even though he had absolutely no spoken words, only babbles and signs. I would be really good for a while, and then start to drift back into my own head. At those times, I at least tried to tell him what I was thinking, but that was hard too because it takes so much longer to think out loud than just to yourself, and I would get impatient.

Another thing that has helped J and I is sign language. It may seem counter intuitive to teach him a second language when he is struggling with English, but just having a few dozen signs has enabled him to really join the conversation. When I ask him questions, he can respond in richer ways (not just pointing, screaming, and stomping his feet, although that happens a lot too) In fact, today, for the first time, I was able to ask him how he felt and he answered “happy” and smiled. It was so touching to be able to connect with him like that, and makes me want to talk to this little guy and get to know him even more.  Another positive side affect of this change we are making is that I am more positive with J (another  factors the study found that helped language development). When I am paying more attention to him and less to whatever else, I am not telling him to be quiet, or to go do something else while I finish whatever it is. I never noticed that this was discouraging him from communicating with me. I may miss my hobbies or not have a perfectly clean house, but we have a better relationship and I know he is being encouraged to communicate and that is more than worth it.

We are now expecting a second child, and one thing I will do differently is to put aside my hang ups about talking to a baby. Even if I sound silly, and even if she only responds with coos and smiles, I know it is an important step in learning language (a really complicated task if you stop and think about it) and I can be confident that I am doing all I can to give my child the best start possible.

Please share your thoughts or experiences you have had with speaking to your infant/toddler!

Teaching our Family’s History

What's scary is that all the men on this side of the family look alike, even down to my dad.

My ancestors!

One of my hobbies is to research my family’s history. Maybe I am weird, but I love learning about how my family fits into history. For example, I have ancestors that were there for the 1848 Revolutions in Europe, a great-great-…-grandmother who was expelled from Puritan Massachusetts for her beliefs, and lots of humble farmers that lived quiet lives yet had their own unique personalities. I love thinking that each of these people helped me to be me. I also love the research side of it. I get to look at lots of old documents and records and construct an entire life from little clues just like a real historian, and what is better is that I am finding out things that no one else has ever put together. (Who cares what some farmer in 19th century Canada was like? Well me, because he is my ancestor!) Our family’s history, just like any history, can also provide stories of people overcoming challenges and teach some great values, as well as perhaps some “what not to do”s (every family has some not-so-proud moments). Best of all, it makes me feel special to know where my family came from. I know I want to teach my children about their personal and family heritage for all of these reasons.

But this blog isn’t about my opinions on parenting; it is about research. 

I went to look for research on how learning history benefits children and it was really hard to find. virtually every child education system teaches a nation’s history, world history, local history etc. You would think that if we spend so much effort trying to get our kids to remember all these facts and stories there would be some solid, evidence based reason, but it is precisely because everyone teaches history that there are no studies. You just can’t find a group of kids that never learned any history so you can’t compare their outcomes to those that do learn history. That being said, there is some research on how children learn and understand history.

The research gives some evidence that learning a family’s place in history may be beneficial. A study by Keith C. Barton found that for some reason American children in particular were very curious about their family’s place in history (Irish children were curious about more general historical facts), and all children turned to their family and parents for more information. When they turned to family to gain context, they were able to explain their own lives in the context of history. (“You’d Be Wanting to Know about the Past: Social contexts of children’s historical understanding in Northern Ireland and the USA.” Keith C Barton. 2010;  “My Mom Taught Me”: The Situated Nature of Historical Understanding. Keith C Barton. 1995) Other researchers, Robinson and Stepien, found that when kids were asked about their family’s connection to history they displayed a deeper level of understanding. (Historical understanding, personal epistemology, and the educational experiences of students at a suburban high school: A case study.) So my instinct that learning about grandpa in WWII will help my kids understand the war might be right.

The other aspect of family history research I would like to discuss is the fact that we can teach our children how to search for and interpret primary sources. We can go into old documents  and interpret for ourselves what happened in our ancestor’s lives which is a valuable skill because unlike the way most history is taught: read about in a textbook and accepted as fact, historians are analyzers and often have different interpretations. There has been a very recent resurgence of document based history classes in high schools, and the student outcomes are promising.  One caveat I will add is that analyzing primary sources requires some advanced literacy skills, and without instruction on how to analyze and interpret, students in these situations were only summarizing what they read. (Stahl et. all, What Happens When Students Read Multiple Source Documents in History?, 9 Nov 2011) Fortunately, those skills can be taught, and history is a great place to teach advanced literacy. Also, when history is taught through source documents, students display a more “accurate, grounded interpretation of the past” (Chanuncey Monte-Sano, Beyond Reading Comprehension and Summary: Learning to Read and Write in History by Focusing on Evidence, Perspective, and Interpretation, 21 Mar 2011)

The first really good study of these “Reading Like a Historian” (RLH) classrooms was published in January 2012. They found that in practice, this approach does improve student’s reading comprehension, historical thinking skills, and factual knowledge. They also found that while the best readers had the best results, demographic differences were not a hindrance to the student’s learning. (Avishag Reismana, Reading Like a Historian: a Document-Based History Curriculum Intervention in Urban High Schools, 12 Jan 2012) Unfortunately, these classrooms are pretty rare, and it has been hard to get history teachers to make the paradigm shift towards RLH. Doing this type of learning at home through family history might be a way to supplement their education.

At this point, I got really excited and had to stop myself from getting lost in the research and come back and write this post. If you are getting excited too, here is a great dissertation that takes the above study and a couple others and reviews and discusses them: https://stacks.stanford.edu/file/druid:vv771bw4976/Reisman_Dissertation_ReadinglikeaHistorian-augmented.pdf.

Well, that sounds fun, but I don’t know anything about genealogy research

You are not alone. Practically everything I have learned, I have learned on my own, and along the way I have found some great resources. I cannot recommend FamilySearch.org highly enough. (Disclaimer: it is run by a church, but you wouldn’t know it because absolutely no proselyting or preaching is done through this program. The only thing is that the brick and mortar libraries that are a part of their system are housed in church buildings) The reason I love FamilySearch is that they have a huge collection, and everything is free. The only fee you might run into is the cost of mailing a record to one of their satellite libraries. You can register with them and use their software to build a family tree, organize photos and records, collaborate with other family historians, and best of all get lots of research help. Go here for a step by step guide on to get started: https://familysearch.org/gettingstarted. The first thing you do is just start asking your grandmas, great uncles, etc for stories and take it from there. I think you will find that it is easier than you expect.

I hope you find a few interesting stories to share with your children. It will help them feel more connected to you, and your family. It will help them better identify with and understand history. As you get into doing some of your own research and share this experience with your children, it will also help them to understand the historian’s process, retain historical facts, and even improve their literacy. Maybe it sounds like something you want to try?