Evidence-based living

… and now gluten intolerance may be a real thing.

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There’s a new paper out in Clinical Gastroenterology and Hepatology (online; 1) that suggests that non-Celiac gluten sensitivity IS in fact a thing, despite other fairly recent research to the contrary.

I’ll save the contrary research for another post to keep this short, but in this new paper Di Sabatino et al. gave 59 subjects either 4.375 g/day of gluten or rice starch (the placebo) for 1 week, then switched the groups for the next week. 4.375 g of gluten is about the same amount as found in two slices of white bread, so you’d get that much from eating a sandwich.

Well, Di Sabatino et al. found that this approach resulted in measurable, statistically significant changes in overall symptoms (a measure combining all the individual symptoms they measured). Individual symptoms that were worsened by gluten included abdominal bloating, pain, foggy mind, depression, and aphthous stomatitis (canker sores).

Twenty-three out of 28 other symptoms did not worsen with gluten administration.

I’ll save forming a confident opinion for when more new research on the topic comes out, but at least this paper shows that we have not heard the last word on non-Celiac gluten sensitivity.

1 Di Sabatino, A., Volta, U., Salvatore, C., Biancheri, P., Caio, G., De Giorgio, R., Di Stefano, M., Corazza, G.R. (online 2015) Small amounts of gluten in subjects with suspected nonceliac gluten sensitivity: a randomized, double-blind, placebo-controlled, cross-over trial. doi: 10.1016/j.cgh.2015.01.029

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Evidence-based living

Healthy eating for vegetarians and vegans: what about B-12?

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Many people choose to eat little meat, only eat fish, not to eat meat at all (vegetarians), or not to consume animal products of any kind (vegans). Often these diets are eaten for moral, environmental, or health reasons, yet concerns are often aired that these diets lack important vitamins. Many vegans and vegetarians are very nutrition conscious, and with a few exceptions, careful food choice appears to generally make up for the lack of certain nutrients in an all- or mostly-plant diet.

With pregnancy comes new concerns: namely deficiencies in iron, calcium, folate, and other vitamins become more pronounced, and have greater consequences. Low birth weights, neural tube defects, and a variety of other problems can arise from vitamin deficiencies during pregnancy, especially at early stages during which pregnancy may not yet be detected. Vegetarians and vegans often suffer increased risk of a couple of these deficiencies, for example iron.

Some vitamin deficiencies are largely unique to vegans and vegetarians. B-12 deficiency in particular is common to anyone eating little meat, even non-vegetarians. Symptoms of B-12 deficiency generally appear in infants in their first year of life and can include lethargy, failure to thrive, and a loss of previously established developmental skills, among other possible problems. Severe neurological problems can also result. Folate, another B vitamin, is of common concern for pregnant women because folate deficiencies can lead to fundamental neural problems. Interestingly, folate is generally easy to get appropriate levels of for vegetarians and vegans eating a healthy diet, and high folate can mask B-12 deficiency. Because the problems associated with maternal B-12 deficiency don’t usually appear until the first year of life, this is an important, and potentially overlooked concern for vegan and vegetarian women who are considering children.

Supplementation is the first approach generally suggested, and indeed seems to be effective in many cases. However, there are many examples in which dietary supplements are not as effective as people would like to believe, and in some cases they may even be harmful. Therefore in cases in which the effectiveness of supplements has not been directly studied (and pregnant women are generally not experimented on for obvious reasons) it might be safer to actually include foods in the diet that have important nutrients, obviating the need for supplementation. Secondarily, many people who avoid animal products may also wish to avoid artificially ‘enhanced’ foods, such as vitamin-enriched cereal grains or genetically-modified plants that have B-12 producing genes inserted. So, it may be important to consider true whole-food sources of important nutrients in which specific diets are low.

Interestingly, some foods atypical in the western diet, such as dried purple laver (nori), and fermented foods such as
tempe, already eaten by many vegans, include high levels of B-12. Nori is generally wrapped around sushi rolls (avoid the fish rolls if pregnant due to heavy metal and probably parasite concerns), but can also be eaten in salads, on sandwiches, or for the other Midwesterners out there, in hotdish!

TL;DR vegans and vegetarians may have a few extra things to think about when choosing to become pregnant, but they can be solved through appropriate prenatal care with supplementation, and ideally very carefully chosen and potentially atypical dietary items such as nori

1) Bleys, J., Miller, E.R., Pastor-Barriuso, R., Appel, L.J., Guallar, E. (2006) Vitamin-mineral supplementation and the progression of atherosclerosis: a meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition. 84 (4) 880-887

2) Chalouhi C., Faesch, S., Anthoine-Milhomme, M.C., Fulla, Y. Dulac, O. Cheron, G. (2008) Neurological consequences of vitamin B-12 deficiency and its treatment. Pediatric Emergency Care 24(8): 538:541.

3) Koebnick, C., Hoffmann, I., Dagnelie, P.C., Heins, U.A., Wickramasinghe, S.N., Ratnayaka, I.D., Gruendel, S., Lindemans, J., Leitzmann, C. (2004) Long-term ovo-lacto vegetarian diet impairs vitamin B-12 status in pregnant women. Journal of Nutrition. 134: 3319-3326.

4) Kuhne, T., Bubl, R., Baumgartner, R. (1991) Maternal vegan diet causing a serious infantile neurological disorder due to vitamin B12 deficiency. European Journal of Pediatrics 150: 205-208.

5) Miller, E.R., Pastor-Barriuso, R., Dalal, D., Riemersma, R.A., Appel, L.J., Guallar, E. (2005) Meta-analysis: High-dosage vitamen E supplementation may increase all-cause mortality. 142 (1).

6) Stabler, S.P. (1999) B12 and nutrition, p. 343-365. In R. Banerjee (ed.),Chemistry and biochemistry of B12. John Wiley & Sons, Inc., New York, NY.

7) Watanabe, F., Yabuta, Y., Bito, T, and Teng, F. (2014) Vitamin B12-Containing Plant Food Sources for Vegetarians Nutrients 6(5) 1861-1873

Evidence-based living

Should we refer to obesity as a disease?

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I just read an interesting paper reviewing a few articles looking at the effects of a disease-based approach to obesity education. In brief, the authors reviewed previous studies they had carried out. On June 18th, 2013 the American Medical Association classified obesity as a disease. The authors of this study found that when given the message through a New York Times article that obesity is a disease, obese people were less concerned about their weight, less interested in dieting, and made higher-calorie food decisions compared to a similar group of people (the control group) who were given a alternative (non-disease based) informational description of obesity. Interestingly, people in the study who were presented with the information that obesity is a disease reported lower levels of body dissatisfaction.

In summary, telling people that obesity is a disease might make them happier with their weight, while simultaneously making them less likely to lose weight. It is obviously very important that people be happy with themselves at whatever weight they are at, especially given the degree of shame imposed upon overweight people. Nevertheless, the resulting increased risk of other health problems that either are caused by obesity or co-occur with obesity, such as diabetes, heart disease, joint problems, and even some kinds of cancer certainly puts a burden on health care practitioners to be careful in such nuances as to how they refer to obesity (as a disease, or as a result of lifestyle choices).

TLDR. Calling obesity a disease makes obese people feel better about their weight, but also makes them less interested in losing weight, and less likely to make healthy decisions.

Over the next couple weeks I’ll read a few related articles and report on how the authors’ conclusions hold up. For the near future my blog will stick to this style, reporting on an interesting paper I have read recently.

Crystal L. Hoyt, Jeni L. Burnette and Lisa Auster-Gussman (2014) ‘Obesity Is a Disease”: Examining the Self-Regulatory Impact of This Public-Health Message. Psychological Science. 25: 997 originally published online 24 January 2014. DOI: 10.1177/0956797613516981

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New posting tactic – shorter posts!

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So, I’ve found that it is often difficult to keep up on blog posts. I think I’m not the only one who has this problem. My new goal is going to be to treat my blog like a slightly longer Twitter feed. By this I mean, I will be posting thoughts, pictures, and short things I write without worrying so much about content for a while. This is not my long-term goal, but rather a tactic to get more written and posted. If anyone has thoughts on this, let me know.

I’m currently preparing for SICB 2015! The annual meeting of the Society of Integrative and Comparative Biology is January 3-7, 2015. I’ll be leaving early on the third. I just got word that my poster, and that of one of my undergraduate mentees, Casey Lardner, finished printing, so everything’s ready to go! I think it will be a fun year, with a lot of great science. I will share more details about the research I am presenting soon.

To science!

Butterfly research

Butterfly food!

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It’s been so nice outside lately, and butterflies are finally coming out! I have reports from others in the lab that commas and mourning cloaks have been seen recently. I’m very excited for field and lab work to start this summer. Until I start getting lots of local butterflies, I’m trying to make sure I have enough food for larvae to eat. Because collecting plants last year turned out to be pretty hit or miss, and often a lot of work, this year I’m trying to grow nearly everything. I thought I would share some of the variety of plants that I’ve been growing to prepare for butterfly season.

Butterflies eat all kinds of things as larvae; some butterfly food doesn’t seem like it would be very pleasant, like the milk thistle I’m growing…

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… or the stinging nettle.

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Others are fun, like this FALSE stinging nettle, which I didn’t even know existed. It looks a lot like stinging nettle, and the same butterflies eat it, but it doesn’t sting!

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I’m also growing blueberries, currants, gooseberries, apples and cherries (butterfly larvae love the leaves, but they don’t eat the fruit).

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I’m actually growing more than 20 different kinds of plants to try to find the perfect food fora  bunch of different butterfly species. I even have hops plants, which make the hops flowers used to flavor and bitter beer, and the leaves of which are eaten by a few different butterfly species.

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Hopefully this summer, the butterflies will find that they have more than enough to eat with this smorgasbord of leafy delights!

Do you have any experience raising some rare plants so you can rear butterflies?



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Should faculty have a major role in decisions about hiring and firing?

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I’ve seen a couple news stories recently about professors being fired from long-term, nontenured positions.

The stories themselves were often fairly alarmist about the state of the job market for academics, and part of the concern was that the firing decisions had been made by administrators without consulting the faculty in question. The comment sections on these stories were interesting. Although some were sympathetic, most seemed to suggest (to paraphrase) that it’s about time that these elitist, ivory tower academics got a taste of indiscriminate layoffs like the rest of us. This sounds like I’m setting up a straw man, but that was the general tone.

I’m not sure what to make of most of this. It kind of felt like everyone really hates professors for some reason. There are numerous possible topics of interest here.

One point I thought was interesting was the general feeling that it was utterly ridiculous to expect that the ’employees’ (ie. the professors at the college) be given any kind of say in the decisions that the ’employers’ (ie. the college administration) make about employment. A couple articles suggested that the administration’s failure to involve the faculty in the decision was particularly treacherous, an idea that was really derided in the comments section.

To put this in context, it might help to remember how specialized research areas can be. It is probably fairly common that people in administrative positions do not fully understand much of the research being done at their institution, nor have they taken the majority of classes offered. In fact, it is pretty unreasonable to expect that of someone who probably had to learn a lot about the practicalities of management to do their jobs. As a result, administrators often may not have a good grasp on the actual quality of individual employees, and may need to involve the employees themselves, and their peers, to fill this gap.

As a result, faculty generally play an important role in decisions about who gets hired, who gets tenure, and who gets promoted, etc.. For many people, this probably does seem ridiculous, but if it’s difficult for the employing institution to distinguish among high- and low-quality researchers and teachers, then maybe a professor’s peers are the best judges. Administrators may still be the people needing to make decisions about when hiring and firing needs to be done, but when the entire faculty is kept out of the loop, some poor decision-making could result.

Thoughts?

biology

What are hormones and how do they work: some basics

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We hear a lot about hormones these days. Estrogen is good for women; estrogen is bad for women. Growth hormone will help you stay young; growth hormone will give you cancer. Hormones make cows get big and tasty; hormones that we give cows are bad for our kids when they drink milk. But what IS a hormone? Why are they important? How do they work?

To start with, there are three major types of hormones – peptides, catecholamines, and steroids. Each one is different. But all three are released in response to a signal from the brain (or another hormone), and travel throughout your body in your blood, affecting cells and tissues along the way. Hormones are important before you are born, and until you die. They control how your body develops, and influence your behavior.

Peptides are proteins – they are produced within cells, and are represented by one gene. Insulin is a well-known example of a peptide hormone. Peptide hormones bind to receptors on the outside of cells, which results in complex signalling cascades (like a waterfall of biology inside the cell). These cascades eventually influence how DNA is turned into new proteins that will have different effects.

Catecholamines are kind of like amino acids, and function a little like peptides – binding to the outside of a cell. Epinephrine and dopamine are examples of catecholamines. Catecholamines can also be important in the brain.

Steroid hormones are the third major type of hormone, and perhaps the best known. Testosterone and estrogen are both examples of steroid hormones. Steroid hormones are similar in structure to cholesterol molecules, and in fact cholesterol is a kind of non-hormone steroid. Steroids differ from catecholamines and peptides in that they are able to enter cells. Instead of binding at cell surfaces, steroids can actually go straight to the DNA and have direct effects.

There are several more generally important things to recognize. First, the systems within cells that respond to hormones are very complex. Second, individuals vary genetically in how we produce hormones – your genes DO affect your life in many ways. Nevertheless, production of hormones from genes occurs in response to the environment – for example, insulin is produced in response to eating sugar. So what you do in life, what you think, and what you experience influences your hormones, which then influences your physical body. Hormonal systems are complicated and can affect each other. If you have a disorder that is characterized by low levels of a hormone, it can be difficult to figure out exactly what’s wrong – do you produce too little, does your body break it down extra fast, or is something else going on? Finally, there are other types of signals in our bodies – for example, ‘neurotransmitters’ work somewhat like hormones, but are in our brains. ‘Cytokines’ are another important signaling molecule that is especially common in immune function.

How hormones influence our outward traits, or ‘phenotypes’ is a complicated question, but hopefully this is enough of a background allowing readers without a background in biology to understand mention of hormones in future posts.

biology

Winter is coming and the basics of trade-offs in biology

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Winter is coming and the basics of trade-offs in biology

Butterfly season is over and it’s getting cold out, although I did just see a cabbage white flapping around erratically when I was walking to work this morning. Despite the troubles we had early on in the summer with butterflies dying, we did manage to collect some good data. More importantly, I think that we worked most of the kinks out of our experimental design so next year should go much smoother. Now that I have the time, I’m going to sit down and try to explain my research project, and why I am doing it. The explanation will take 3 posts, so I can take my time explaining the concepts to interested folks who are not biologists.

One of the basic concepts underlying my research is that of a trade-off. A trade-off occurs when an organism wants to do two different things, but has a limited amount of some important resource. The resource could be time, calories, vital nutrients, or many other things. A simple example from everyday life would be trying to buy both a television and a bike with a limited amount of money. You can’t afford an expensive television AND an expensive bike. Instead, you have to choose between a cheap television and an expensive bike, a cheap bike and an expensive television, or a moderately priced bike and a moderately priced television. You would ideally want both an expensive bike and an expensive television, but you are limited by a resource: money.

Trade-offs in biology work similarly, but often the mechanism or the resource are not fully understood. This would be like seeing someone with a cheap bike and an expensive television, but not knowing WHY they have a cheap bike. You can guess that they have a cheap bike because they have limited money and want a nice television more than they want a nice bike, but you can’t know for sure. To biologists, this often takes the form of the observation that species rarely exhibit ‘perfect’ combinations of traits that are evolutionarily important, such as lifespan and reproductive rate. Some species, such as elephants, are very long lived, but reproduce very slowly (see Figure 1). Other species, such as mice, reproduce extremely rapidly, but are also short-lived. Slow reproduction with a short lifespan is clearly not a good strategy, and should generally not evolve. Conversely, an ideal combination from an evolutionary perspective would be to live a very long time and also have lots of kids really fast*.  Nevertheless, this is rarely seen in nature. Biologists generally agree that this pattern means that there is some cost to reproducing rapidly, and therefore species that reproduce rapidly will not live as long. There are many other examples of traits that are similar involved in trade-offs, such as brain size, muscle strength, and growth rate. Essentially, any trait that is important in fitness but requires some limited resource will likely exhibit trade-offs.

Reproduction and lifespan tradeoff more detail

The same patterns are generally seen within species as well, but individual trade-offs are often less consistent within species than they are among species. The specific ecological considerations of individual species may play a role, or it may be because there is simply more extreme variation among species compared to within species. In other species, some individuals may simply have access to more resources than others, meaning that despite the potential for a trade-off if resources are spread evenly across individuals, no trade-off is apparent due to inequalities among individuals. Someone who makes more money than you gets to have both an expensive television AND an expensive bike, avoiding the trade-off. In my next post I will talk about how hormones influence traits within species, and then finally I will bring together the ideas I’ve presented within the larger framework of my current research.

*There are some persuasive, but more complex considerations that I’m not covering here – for example in some cases longer-lived species may benefit disproportionately from intensive parental care, which may itself trade off with offspring number. However, the idea of a trade-off being responsible is widely accepted, and therefore I will not discuss these other possibilities further.

Butterfly research

The great butterfly apocalypse (butterpocalypse) of 2013

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I had a dream the other night. I was working at my desk, when suddenly, cabbage white butterflies (like the one in the picture) started raining down all around me, dead or dying. I tried to save them, but I couldn’t move. I screamed, down on my knees; a long, drawn out, “Nooooooo!”. It was very dramatic – think Charlton Heston at the end of planet of the apes, when he finds the statue of liberty and realizes he was on Earth all along (spoiler alert!).

Small White butterfly (Pieris rapae)
Small White butterfly (Pieris rapae) (Photo credit: Wikipedia)

Then I woke up. As my dog Darwin realized I was awake and started licking my face, the thought occurred to me that it was one of those dreams that you wake up from, but then once you’re awake you realize that what you were dreaming is really happening. At least allegorically – like the dream was a big metaphor for my life.

Spring this year was cold and wet, and most of the butterflies decided to sleep in until midsummer. They are out now, but as far as I can tell, they are still not common. Perhaps they hide from me, scheming little butterfly schemes.

I need to raise a whole generation in captivity if I want to use them for research, so when I catch females, I try to get them to lay eggs. Sometimes they do lay eggs. Sometimes they don’t lay eggs. Often they just die, lying on their sides and breathing laboriously (metaphorically again – insects don’t have lungs) in their little white mesh butterfly houses with their potted plants and sugar-water feeders.

Most research projects I’ve worked on involved watching animals in the wild, collecting them temporarily and then re-releasing them, or analyzing data that other people had collected. None of these were easy. Nevertheless, I think that simultaneously raising a number of butterfly species in captivity, and trying to keep them happy and healthy, is one of the hardest things I’ve tried yet. Perhaps the worst part is having to continuously rethink my plans. It’s amazing how hard one can think and plan for something, but then when you actually try to DO it, everything immediately falls apart.

Learning that all your preconceptions were actually misconceptions is pretty normal for science, and probably for life in general. But that doesn’t make it any less frustrating. Learning is hard. For now I’ve got some good ideas of what to try next, lots of help and advice from my mentors and friends here, and a lot of adult butterflies provided by some very nice people that should help me out by laying the next generation of eggs. Fingers crossed!

Next time I post I’ll try to get into why I even want to raise butterflies in the first place.

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First post!

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Hi!

I’m Eli, and I recently started a postdoc at the University of Minnesota, working with Dr. Emilie Snell-Rood.

Picture of Eli Swanson
This is me!

I finished my Ph.D. at Michigan State in the spring, started here in June, and will be working here for a few years. I liked living in Lansing, but I’m originally from Minnesota, so I’m excited to be back!

The purpose of my blog is to talk about my research and what I’m learning, discuss the research process, and share any good stories that come up along the way. The project I’m working on here is a huge change for me, because all of my previous research experience was with either frogs or mammals, and now I’m not only working with butterflies, but trying  to raise them. I will be trying out lots of new field and lab techniques for working with invertebrates (like how not to accidentally squish them!). I will also be doing a great deal of programming and evolutionary modeling whenever I can find a break from my adventures in husbandry. During my third year here I plan to teach two classes, and hopefully take a couple graduate education courses.

My research focuses on hormones, life histories, and evolution. Life histories describe aspects of an organism’s life such as how fast they grow, how big they get, how much they reproduce and when, and how long they live. Life history traits are important because they describe reproduction and survival, and therefore are the building blocks of evolution. Specifically, I’m interested in how hormones simultaneously influence multiple life history traits, and how hormones and life histories evolve together. I will get into more detail about who I am, my research, and my plans for the next couple years in future posts. I also have some alternative formats planned such as video and animation that should help people understand my research and what I’m learning in some more dynamic ways.

I’ll post again soon,

Eli