CW: discussion of body weight change in the context of nutrition research.
This week, while skimming the weekly newsletter I get on new nutrition and metabolic research on body weight, the following caught my eye:
No significant changes in body weight, body mass index, % body fat, and neither in visceral adipose tissue in response to intervention was seen in the avocado group compared to the control group.
Catchy, huh? Could avocado have replaced the egg as the center of nutritional controversy? Turns out, people are have many questions about avocados.
The new avocado study I quoted above is out to settle the matter. But first, a little background about avocados (from the paper):
Okay, glad that’s settled. Now, what’s the answer? Are avocados good for you or bad for you?
Turns out, they’re likely neither. The researchers were unable to find any significant differences between the avocado-consuming and the control group:
No significant changes in body weight, body mass index, % body fat, and neither in visceral adipose tissue in response to intervention was seen in the avocado group compared to the control group.
Avocado consumption didn’t seem to produce weight loss or weight gain (as they also mentioned in their abstract). They found some potential benefits relative to the type of fat found in avocados, but as they say, “further studies are needed to elucidate this effect.”
So, go forth and eat avocados. Or not, as you please. But I recommend this guacamole recipe from the California guacamole board. Who can resist?
Is there any food item more hotly contested for its potential deadliness to breakfast (and other meal) eaters than the egg? Yes, coffee comes under attack regularly. But, Time magazine went on record to support coffee drinking “in moderation”– a wimpy recommendation, but it puts coffee in the clear. For now…
Uh, where was I? Oh, eggs. Right. There’s a new study out– a large prospective study that has people fill out Food Frequency Questionnaires and then follows them until the study ends (it ran for 16 years). And it found a small increase in relative risk of death (7% on average) for those who reported eating half of a whole egg per day (meaning 3.5 eggs a week on average). The researchers speculate that the ovo-risk is due to increase in dietary cholesterol intake.
In other words, eggs are bad. Again. Or are they?
Of course, the news folks are all over the latest eggy results. Here’s one headline from this story:
What are we to make of this latest grim pronouncement about eggs? Is it true? Should we be afraid? Should we fight back? What to think?
First, some perspective is in order. Nutritional studies have been ping-ponging back and forth about eggs for decades now. As an avid egg-news follower, I’ve personally written several posts about the changing fortunes of eggs over the years.
Why do I distrust this new study telling me that eggs are bad? So glad you asked. Here are a few reasons:
Reason one: the study uses food frequency questionnaires, which are notorious for being bogus evidence. Or, as this journal says about them, “the main limitations are systematic errors and biases in estimates.” Ouch.
Reason two: the increased relative mortality risk was 7%, of which it was unclear even to the researchers how much of that was due to egg consumption. They put it this way in the abstract:
Study limitations include… residual confounding despite extensive adjustment for acknowledged dietary and lifestyle risk factors. Ouch.
The conclusions of this study are overblown. Blaming eggs alone for an increased risk of cardiovascular disease is a simplistic and reductionist approach to the concept of diet and disease prevention. (ouch)
Despite many years of research this question about eggs and health has not been answered, with multiple observational studies over the last few decades showing conflicting results… This study, although well conducted, unfortunately only adds more noise to the discussion. (yep, what I said)
The suggestion that the risk from eggs is mostly explained by the cholesterol content of eggs is also problematic as we know that dietary cholesterol does not have a clear link to levels of circulating cholesterol in the blood. (yep, knew this too; you go, egg expert!)
How many eggs’ or ‘how much cholesterol’ was based on a questionnaire, which asked people how often over the past year they ate eggs and other foods and which people only completed once. So it did not look at how peoples food intake changed over the following decade. (Yeah! One questionnaire about a year’s worth of eating and then… nothing…. Seriously?)
In short, studies have been trying to put eggs down, and they’ve kept getting back up (in a manner of speaking). But, you may be wondering, is it okay for me to eat eggs?
According to nutrition science: they have no earthly idea.
According to me: it doesn’t mater what I think about what you eat. Eat what you want; it’s none of my business (unless I’m making breakfast for you, in which case we should confab about it).
According to you: all kinds of decisions and preferences and values and constraints go into what you put on your plate. They are yours. Looking for guidelines is natural, and there are a bunch of nutritional ones out there. But those guidelines also reflect values and preferences and constraints and funding sources and particular agendas and perspectives. You get to choose whether you eat eggs, how often and how many.
Does nutritional sensationalism in the press bother you? Do you ignore it? I’d love to hear any comments you have. And if you have a good egg salad recipe, I’d be interested in that, too.
CW: this post offers comments and critiques on a research article whose subject matter is methods for weight loss. The focus of this post is not to endorse any method of weight loss (because I don’t). I’m reframing the area of research as metabolism of body weight– how that works. I then point out how difficult it is to get clarity and confidence from scientific articles about this topic when the researchers as a group are in conflict.
Now, to the post:
Right now, the state of coronavirus research is what I would call the Wild Wild West. There’s not much law and order, shootouts among rival factions are common, and the most vulnerable among us are completely unprotected. But that’s understandable– COVID-19 is less than a year old, so researchers are starting from scratch, and many of them are working while at the same time taking care of patients who urgently need effective treatment.
But no researcher who works on human metabolism of body weight has these excuses, as it were. Trying to understand how body weight changes work– fluctuations up and down, how and when bodies maintain stable weights over time– is a well-established set of research questions with a long history of practices and accompanying literature.
So, what’s the deal here? What do we really know? What’s in dispute among researchers, and what’s just pseudoscientific fat-phobic nonsense?
(tl:dr version– I don’t have a good answer to this question. But, neither do the researchers, and there are reasons why they don’t that aren’t scientific ones.)
In a 2013 New England Journal of Medicine article, a research group took on the task of dividing up myths, presumptions and what they called facts about how body weight metabolism works. Some of their cited “myths” (I’m using scare quotes because whether they are myths is contested) included:
how breast feeding affects body weight;
how sex counts as physical activity or exercise;
how physical activity classes affect body weight;
claims about how different eating practices affect long-term body weight stability (see article if you want the details, but they’re not important here).
The researchers considered these to be myths because, according to their analysis, the studies they cite don’t support the above claims.
There’s more to the article (they also talk about what they call “presumptions” and “facts” about body weight, but I’ll leave that to the reader, as they say), but here’s the catch.
Many other researchers and experts didn’t and don’t agree with their conclusions. Why not? There are a lot of issues with their work, but one big one is this:
The primary researchers got a lot-a-lot of funding from Kraft, Jenny Craig, the Knowledge Institute for Beer (no, that’s not a joke), McDonald’s Global Advisory Council (which is also apparently a thing), and yes, Coca-Cola. The list goes on and on, and it’s fascinating reading. Go to the bottom of the article, and enjoy.
Getting serious, though: we know that the money for scientific research has to come from somewhere. Federal funding doesn’t cover all of the needs of all the scientists. Partnering with business and industries is common. And good solid science has been established doing just that.
But: when the connections among scientist, funding source and recommendations to the public get too close, we may be well-advised to take a step back and reconsider. In this case, one of the so-called “facts” cited was that meal-replacement drinks and commercially produced meals were an effective (and safe? not clear) eating practice that could result in lowered body weight (that would be stable? again, not clear). But the funders of this research included companies that would directly benefit from public uptake of this claim.
You might think, hmm. This was seven years ago. Surely this mess has been cleared up by now.
As my friends and I used to say in middle school, “you wish!” Alas, nutrition and human metabolism research (as it relates to body weight) is still in full Game-of-Thrones mode (yes, I switched from a Wild West to the Games of Thrones metaphor in the same article; so sue me…)
Does this mean we don’t know anything? Well, no. We know that there are lots of foods to choose from, that we all have nutritional needs, and there are lots of ways to fill those needs. We know that physical activity has loads of benefits for our well-being.
What about the nitty-gritty details, though? Those, my friends, are most definitely still under construction.
Readers: what are some of your favorite “myths” around this topic? I’d love to hear from you.
“Mice form the basis of all biomedical research. As the quintessential model organism, they are perfect specimens in which to study all sorts of human conditions. But just because a drug performs well in mice, that doesn’t necessarily mean it’ll have the same result in humans. Science journalists and press releases — as translators of these findings — often fail to clearly demarcate that line.
A new Twitter account hopes to make that line much clearer. Last Friday, tweets from @justsaysinmice started making the rounds on Twitter and they quickly went viral. Every tweet — all 11 of them so far — follows the same pattern: A news story or press release with a sensational headline is tweeted out, with two simple words tacked on top: “IN MICE.””
The story that caught my eye was on orange juice, partly because of a playful ongoing argument with a friend who is quick to remind me and others that OJ is the nutritional equivalent of coke. Not evil, but not exactly health food.
“A new study from London’s Western University suggests drinking two-and-a-half glasses of orange juice a day could help prevent heart disease and diabetes. Researchers have found a molecule, called nobiletin, in sweet oranges and tangerines that significantly reduces obesity and can reverse its negative side-effects.“Obesity and its resulting metabolic syndromes are a huge burden to our health care system, and we have very few interventions that have been shown to work effectively,” said Murray Huff, PhD professor at Western’s Schulich School of Medicine & Dentistry in a statement.”
Hmm. But read on and the results were only shown in mice.
So I tweeted.
Medical researcher and occasional guest blogger Dr. Savita weighed in.
Sounds like unless you want 20g of sugar and you just want the health benefits, if the results work out in humans and not just #inmice, there are better ways to get it.
Continuing with the discussion of make-ahead meal preparations, today I thought I’d tackle lunch. Christine nudged me this way during my previous post on oatmeal, and I admit, I started with oatmeal because it was easier to describe and to write about! The trouble with lunch is all the pieces you need to have ready in advance in order to make the prep painless. Over the years, I’ve developed routines to make this pretty easy for me, but it took a while, and many Sundays spent too long in the kitchen, to develop the routine. However, I kept plugging away until it became habitual, and now I spend less than an hour prepping lunches for the week (sometimes a lot less), which works out to under 10 minutes per meal.
So, I am going to write this post with two parts, “Saturday” is going to be the prep that needs to happen before you want to make your meals for the week. This doesn’t have to be Saturday, of course, but at least a day before you need those ingredients. Judicious use of your freezer space can allow you to do this part weeks in advance, and as you develop a meal-prep routine, I strongly suggest you do it that way. “Sunday” is your meal-prep day. I always make enough to eat one of them that day, so then lunch planning is done.
A final note before I get to the recipes–you are going to have to experiment with how much variety you need in the week and from week to week. I do not require much variety to be satisfied with my breakfast and lunches. When I was single, I also ate the same dinner for four or five nights in a row. However, I know many people would be very disappointed in their meals to have so much sameness day to day. You will have to adjust these plans to meet your meal-variety needs, but be aware that the more variety you decide to require, the more time the preparations will take. Easy switches like a different serving of fruit or vegetable may be enough to give you a hit of variation without throwing off the whole week of preparations.
Saturday Prep your protein. My go-to is boneless skinless chicken breasts and/or thighs cooked in the slow-cooker on low heat for many hours. You can also do these in a low oven 20-30 minutes on a baking pan. I usually fill my slow-cooker to the top and leave it on medium for the day. This gives me enough chicken to last a month or so. Whatever I don’t need this week will be chopped up, placed on a cookie sheet and frozen individually. Then, once it’s frozen, I put it in plastic zipper bags to be pulled out as needed for the next month. You could sub in cooked ground or roasted turkey easily enough. I do not eat red meat, but I’d guess you could do something similar with beef. If you want fish or seafoods, I would recommend you keep them frozen until a day before you want to eat them to avoid spoilage.
Prep your grains/beans. Whenever I cook rice, barley, dried beans, lentils, quinoa, etc. for dinner, I make extra. Then I freeze the leftovers in convenient amounts (3 cups, if I’m going to add them to lunches.) Thaw just before you do your prep for the week. I often use canned beans to save time. Just drain and rinse in a colander before using. You can also find cooked grains and beans in the freezer section of the grocery store, and they work well, too.
Consider prepping vegetables. I “cheat” and buy frozen veggies these days, but when I had fewer financial resources and more time, I would buy fresh vegetables, chop and steam them to have ready for lunches all week.
Sunday Basic “boxed” lunch This is my go-to lunch. To make it interesting week in and week out, I change which variation of flavorings I use. This is the starting place.
Put out 6 reusable 4 cup containers with good lids.
In each container begin with: 1 ½ cups chopped, cooked vegetables (I like broccoli, carrots, cauliflower, summer squash, and/or green beans, it’s ok if they’re still frozen) 4 oz chopped chicken, turkey, or protein of your choice (also fine if frozen) ½ cup beans and/or brown rice, quinoa, or other cooked grain (more if you’re vegetarian)
Teriyaki boxed lunch variation Add the following to each container of the the basic boxed lunch: Use black beans or small, mild-flavored beans like azuki or black-eyed peas ⅓ 8oz can of sliced water chestnuts, drained (about ¼ cup) 2 Tbs prepared teriyaki sauce (I use Kikkoman Takumi collection original) 1 tsp toasted sesame oil 2-3 tbs cashews Suggested fruit pairing: tangerines, oranges and/or pineapple
Tex-Mex boxed lunch variation Use pinto and/or black beans and rice. Either use a prepared salsa or make a spicy tomato sauce by stirring together: 2-3 cups tomato sauce 2 tsp cumin 2 tsp chili powder hot pepper flakes to taste
Put ¼ to ½ cup sauce/salsa over the veggies. Sprinkle with 1 tbs. pumpkin seeds. Add 1 oz grated monterey jack or pepper jack cheese on top. Suggested fruit pairing: diced melon and/or papaya (with a squeeze of lime!)
Italian boxed lunch variation Use garbanzo or white beans. Either use a prepared marinara sauce or make one by stirring together: 2-3 cups tomato sauce 2 tsp dried basil and oregano 1 tsp dried thyme 1 minced garlic clove
Put ¼ to ½ cup sauce over the veggies. Sprinkle with 1 oz grated mozzarella cheese and 1-2 tbs. parmesan. Suggested fruit pairing: grapes or an orange
For each of these, when you’re ready to eat, simply remove the lid and heat them up until hot, 3-4 minutes in the microwave. This is what I’m eating these days, although I’ve gone through periods when I was eating soups, stews or big salads instead. I’d be happy to share some of those recipes and ideas in future posts if folks are interested, so let me know and keep an eye out for them!
Do you have a go-to lunch that you like to make ahead for the week? Please comment below, and do let me know if you try any of these and what you think!
Marjorie Hundtoft is a middle school science and health teacher. She can be found eating out of reusable containers, picking up heavy things, and putting them back down again in Portland, Oregon. You can now read her at Progressive-Strength.com .
Catherine recently mentioned her desire to do more meal prep. I love to prep ahead my meals for the week. I have a Sunday routine in which I make enough breakfasts and lunches to last me through Friday. These little containers give me peace of mind–reassurance that I will be well-fed without a hassle all week. If dinner has to be on the fly, that’s somehow more manageable than breakfast or lunch. For me, the hardest part of making meal prep a routine was consistently coming up with the plan before I went to the grocery store on Saturday. If I forgot to think about the entire meal–forgot a serving of fruit, or didn’t think to check if I had enough eggs–then the meal prep would be off for a whole week. So, in the spirit of helping others prep, I thought I’d share some of my recipes and shortcuts.
I eat oatmeal at least 6 days a week, sometimes twice a day. Here are some of my favorite ways to prepare it in advance. I make it a complete meal with coffee, a couple eggs, some plain Greek yogurt and fruit, if there isn’t some added to the oats already.
Easiest Apple Oats. This is my go-to oatmeal. It is endlessly variable, depending on what sounds good to me and what fruit is seasonal at the time. Apples are the easiest, since they stay pleasant all week, whereas pears, bananas, peaches and such can eventually become brown and soggy. Canned or dried fruit are options as well, of course.
1. Set out as many reusable containers with tight lids* as meals you are preparing ahead (I make 6 at a time, eating one the morning I prep). In each container, place the following: ½ cup old-fashioned oats ¾ cup water a sprinkle of cinnamon 1 tbs coarsely chopped nuts 1 tbs raisins, dried cranberries, or cherries ½ a chopped tart apple
2. Store covered in the refrigerator. When you are ready to serve the oats, remove the lid and cook in the microwave 2 minutes, or until the oats have soaked up the liquid.
3. Serve with a little brown sugar, milk/nondairy milk, or Greek yogurt on top.
Slow-cooker Steel-cut oats These are just as easy as the last recipe, you just cook them ahead. Using the slow-cooker allows you to avoid the regular stirring and management that cooking steel-cut oats on the stove-top requires. These cook in about 30 minutes on the stove, if you want them faster, but be aware that they can stick and burn if not regularly stirred.
1. In your slow-cooker, place the following: 1 ½ cups steel-cut oats 6 cups water Tsp or so of cinnamon and/or anise seeds
2. Cook on low heat overnight, or at least 8 hours, until most of the liquid is absorbed and the oats are chewy.
3. If you want to add fruit, add it now after it has cooked. Otherwise, it breaks down over the long cooking time and becomes unpleasant. Optional add-ins to stir in now: 6 Tbs raisins or other dried fruit, chopped if appropriate 6 Tbs chopped walnuts or other unsalted nuts 3 chopped apples
4. Divide into 6 containers, cover and refrigerate until needed.
5. Serve warm by reheating in the microwave when you’re ready to enjoy it. This will thicken up considerably when it cools, so I like to serve it with milk (or actually soymilk, since I’m lactose intolerant) and a bit of butter and brown sugar.
Muesli I like this variation in the warmer months or when I need to pack breakfast somewhere where the extra liquid would be unwelcome. (Note that TSA might give you a side eye on this one, so I don’t recommend it for breakfast on a morning flight in the US.) Multiply the basic recipe by as many servings as you want in advance.
1. Using a wide rubber spatula, stir together in a large bowl: ½ cup old-fashioned or quick oats ¾ cup plain Greek yogurt ½ tsp vanilla (cheap fake vanilla is fine for this) ½ coarsely chopped apple 1 tbs chopped nuts dash cinnamon optional but recommended: ½ chopped orange or a whole tangerine some grated citrus zest
2. Press the mixture into a container that seals well and store up to 5 days. Optional but delicious–drizzle with a little honey before enjoying!
Your turn: do you have a favorite way to prep oatmeal in advance? I’d love to hear about it! And do let me know if you give any of these a try and how it goes!
*Oh, as a side note, any reusable container with a good lid will do for these. We have switched over nearly entirely to a set of Pyrex storage bowls in the last year. The lids are pretty tight (sometimes there’s a little liquid loss in transit, if I’m packing it to work in the morning), and the bowls are nice to reuse since they don’t take on flavors like plastic can. I caution you to not heat the lids, if you have these, though. They do not hold up well in the heat.
Marjorie Hundtoft is a middle school science and health teacher. She can be found eating oatmeal, picking up heavy things and putting them back down again in Portland, Oregon.You can now read her at Progressive-Strength.com .
There’s a story we tell here on the blog. Do the things you love, whatever movement fits into your day is good movement, eat what your body feels like eating.
Regular readers, you know our drill. It’s a relaxed, forgiving tune we sing around here most of the time.
Regular readers know too that I’ve been struggling a bit with that tune. These things are all true, I still sing that song, but at the same time things are getting more complicated with age and with injury. I’ve written before about doing things that aren’t fun (so much painful knee physio!) and about rest. Tl;dr: It’s complicated and sometimes I get frustrated.
It’s especially more complicated as we age. It’s especially more complicated for those of us with performance oriented fitness goals. Martha and Marjorie Rose are serious about their lifting. Kim and I have cycling goals. Others run and race. Cate is often preparing for her next big solo adventure. Christine is training for her next martial arts test.
As a group we’ve got a lot going on. We all do some strength work, some aerobic activity for endurance, some aerobic activity for intensity, and some activities for flexibility and mobility. For me, right now, it’s physio, weights, cycling and yoga.
I don’t mean to sound whiney. I’m not really complaining. It is what it is. But what it is is not simple or easy.
So we’re busy but what do I mean by “more complicated”?
Do you remember when if you had a big project due for work or school you could just stay up all night, maybe even for a couple of nights, and push through? If you were working late you could skip meals, no problem. Aging takes away that ability for most of us. We need to be more organized and scheduled with our work and with our lives.
There are new rules for everyday eating too. For example, there’s a whole list of foods I don’t eat late in the day not because I’m concerned about my weight but because of heartburn. Oh, midlife. Lots of my friends are pretty scientific about their caffeine consumption. Luckily, I can still drink regular coffee after dinner but I think I’m the last in my friend group who is able.
All of these changes are present as we age as athletes too.
Here’s Abigail Barronian talking about the aging athlete, “It’s no secret that our bodies change as we age. Muscle mass and strength decline, it takes longer to recover from hard efforts, and our capacity to handle high training volumes can diminish. On top of that, mobility decreases and we become more prone to certain injuries. When an older athlete stops training, their fitness deteriorates significantly quicker than it did when they were young—and building it back is much harder.”
So given all the constraints it’s hard to be relaxed about things. Fitness in midlife and beyond requires more structure and thoughtful planning. If it used to be the fun, intuitive, freewheeling part of your life, that’s a tough psychological change too. Mostly it’s still a lot of fun for me but these days I’m finding the planning and organizing a bit stressful.
First, as we age rest becomes more important and it’s harder scheduling workouts and scheduling rest days, not to mention getting enough sleep. Aging athletes need more rest between tough workouts. I love rest but even for me sometimes the recommended amount of rest feels like too much. In recent years we’ve discovered that aging athletes can still work out hard. There’s no need to dial back workout intensity but there is a real need to rest more between workouts. We don’t recover and bounce back the way we used to.
A colleague of mine, and former bicycle racer, who is now 59 years old, put it something like this: “In my twenties I recall being able to do five or six hard workouts a week and race back-to-back days without any trouble.
In my thirties this changed to three or four hard workouts a week and it was more difficult to race back-to-back days. In my forties, two or three hard workouts a week were more than enough, and racing back-to-back days was a bit of a challenge. In my fifties, one or two hard workouts a week were enough and recovering from a race took me about a week. Now, approaching 60…don’t even ask.”
The rest and recovery time of a 20 year old athlete is significantly different than that of a 45 year old athlete. It’s different again at 55 and so on. But this means that taking training plans off the internet won’t work. Often they don’t allow enough rest.
From Here’s how to get stronger after fifty: “As you age, your body bounces back more slowly from intense exercise. Successful older athletes should take their recovery as seriously as their training. “Younger athletes can get away with a poor lifestyle and still perform, but older athletes cannot,” Swift says.”
When I was younger it was just a matter of juggling, fitting in the activities I wanted to fit in, amid kids and a busy work schedule. But as we age there’s also the matter of resting between workouts which becomes more and more important. I’ve long been a fan of deliberate rest days and every coach I’ve had has talked about their importance. Except now they’re more important and I don’t have a coach to make sure I take them.
Likewise for lifting, as we age there’s more need for rest. I read a study recently that claimed for midlife women lifters the right ratio for strength training is two hard workouts followed by one easier workout with lighter weights. I’m not sure if that’s right or not but the main point stands, it’s complicated.
I’ve read too that after 50 you should move to two rest days a week of which one can be active recovery, gentle cardio or yoga maybe.
What am I trying to fit in? The big and important thing is knee physio and strength training. Say three days a week. Next up is cycling, also three days a week. I would like to do hot yoga twice a week. And I also want to take a complete rest day. Oh and also I have to be flexible and fit things in around a very demanding work schedule.
Second, food is more complicated too. For me, there’s some planning involved. I have medication I have to take each morning on an empty stomach and then wait an hour before breakfast. That’s tricky. I also have medicine I have to take after breakfast because it can’t be taken on an empty stomach. Oh, and I need to get to work sometime.
There’s also this whole thing about aging athletes and muscle loss. Our bodies use protein less effectively so we are supposed to eat more of it, some with each meal. I also need fewer calories to get through the day–thanks also to aging– so protein takes up a good chunk of the calories. Add vegetables. Where’s the room for other food? That’s not easy to organize either.
Thirdly, for pretty much all of us there are complications related to injury. My knee is an ongoing thing and recently Tracy injured her Achilles. When that happens you’re doing workouts but also physio and in my case massage therapy too. It can feel like a lot to manage.
Now maybe you might think that one doesn’t need to take it all so seriously. You can walk to work, stretch once in awhile, and do work around the house. And that’s true. You can. But if your goals are more about maintaining fitness as you age and not losing muscle, it’s complicated. Mostly I’m good with that. But I confess that some days I just want to not think about what I’m eating or when I’m next riding or lifting and curl up on the sofa with a mug of hot tea and a book.
I don’t know about you, but news headlines with the phrase “early death” tend to capture my attention much more than, say, those with the phrase “second quarter economic forecast”. Here’s one from the Washington Post, warning us against all sodas–with and without sugar. Either way, they lead to our premature demise.
I think the answer is “no, not really”. But of course that’s not the whole story. Why?
The real and longer answer is “we don’t know, based on the results of the study”. So, let’s take a look at that study and the results.
Here’s the Washington post summary:
The study, one of the largest of its kind, tracked 451,743 men and women from 10 countries in Europe. It found that consumption of two or more glasses of artificially sweetened soft drinks a day was positively associated with deaths from circulatory diseases. For sugar-sweetened soft drinks, one or more glasses a day were associated with deaths from digestive diseases, including diseases of the liver, appendix, pancreas and intestines.
The researchers recruited people from Britain, Denmark, France, Germany, Greece, Italy, the Netherlands, Norway, Spain and Sweden between 1992 and 2000, surveying them on their food and drink consumption. Participants were excluded if they reported incidents of cancer, heart disease, stroke or diabetes. Mean age was 50.8, and 71.1 percent of participants were women.
This sounds fairly clearly true, as reported by the Post. So why am I skeptical?
Any big population epidemiology study on nutrition and mortality risk that states some categorical claim is automatically going to raise my antennae. It’s notoriously hard to do this kind of research and get clear results. Why? Think about it for a moment: trying to isolate the contribution to better or worse health over time of the occasional intake of some substance for a whole population is incredibly difficult. For some substances, like tobacco, it turns out it’s pretty easy to establish that it’s harmful in just about any amount. But for, say, alcohol intake, when we graph the risks for drinking it, we get what’s called a J-curve. It looks like this:
What we see here is that, as alcohol consumption increases from zero to about one drink a day, the risk of death drops, and then starts to increase slowly. Looking at it without any other information, you would think that drinking up to say, 5 drinks a day is actually beneficial for your health. Pro health tip: it’s not. But there’s a lot more needed than just this data on this graph in order to understand alcohol consumption and health. If you’re interested in more about J curves, public health and what to do when you get one, look at this nice JAMA article (which is where the graph came from).
Back to the soda study: when we look carefully at the data presented here in the article, what we see is another J-curve. That is, the people in the study who drank between 1 glass a month and 6 glasses a week of soda (either sugar-sweetened or artificially sweetened) had a LOWER risk of all-cause mortality than those who drank less than one soda per month. The risk was a bit higher for those who drank 1–2 glasses of soda (either kind) per day and then higher again for the group who drank more than 2 glasses per day.
When you look at their disease-specific mortality risk data, results are mixed, but there are still J-curves. For women who drank between 1 glass a month and 6 glasses a week of soda, their cancer risks were lower. For men, the risks were mixed, but not appreciably higher. Ditto (almost) for heart-related disease risks (it’s a little more mixed, but a similar pattern).
I would like to thank both Samantha for pointing me to sources and Health Nerd on Twitter for his very detailed analysis of the study (which saved me some time and directed me to particularly interesting data patterns). Here’s the J-curve we see in this study, compliments of Health Nerd):
Does this mean we should all start drinking a little soda a day, to keep the grim reaper away? NO. What this means is that we need to look at the data a lot more closely. Health Nerd points out that the researchers didn’t control for income or ethnicity. We know from various studies that soda intake is higher among Latinx and African-American populations than among White populations, and it’s also higher among lower-income populations. We also know that there are major health disparities in the US both for lower-income and for non-white populations. So, is the soda playing some role in the health of these populations, or not? This is a very important question, and researchers are working on it. But it’s not easy to find a clear answer. And this JAMA study is not, in my view, giving us one.
Lots of people (including me) believe that sodas (either kind) are unhealthy-for-them (according to their views of what healthy-for-them means). There is some scientific evidence that supports this view. What headlines like this do, though, is provide an excuse to scare people and to demonize or blame those who drink soda for whatever happens to their health over time. Looking more closely at what drinking soda means to people seems a good place for public health to start, if the goal is to help people make their own lives healthier-to-them.
Here’s to your health!
Readers– what do you think about soda? Is it a daily part of your life? An occasional drink? Totally off your radar? Do you think it’s the devil, or the pause that refreshes? I’d love to hear from you.
Just when you thought it was safe to go back to the breakfast table: eggs are in the news again, and this time the news ain’t good. This week the nutritional research ouija board people once again asked the eternal question:
And the answer (for this week) is:
Many readers of this blog know that this is definitely not my first eggs rodeo. I follow egg news very closely and make sure Fit is a Feminist Issue followers are always informed of the latest in good-egg-bad-egg research. Here are some of my previous forays into ovo-journalism:
Okay, time to give y’all the 411 on the newest egg nutrition results. There is a serious question that nutrition researchers have been wrestling with for decades: what, if any, relationship is there between dietary cholesterol intake and mortality risk? The answer is (as it always is in real science, especially nutrition science): it’s complicated. Here’s some background from the New York Times coverage of the new study, that came out in JAMA on Friday:
Eggs are a leading source of dietary cholesterol, which once was thought to be strongly related to blood cholesterol levels and heart disease. Older studies suggesting that link led to nutrition guidelines almost a decade ago that recommended consuming no more than 300 milligrams of cholesterol daily; one egg contains about 186 milligrams.
Newer research questioned that relationship, finding that saturated fats contribute more to unhealthy levels of blood cholesterol that can lead to heart problems.
The latest U.S. government nutrition guidelines, from 2015, removed the strict daily cholesterol limit. While eating as little cholesterol as possible is still advised, the recommendations say eggs can still be part of a healthy diet, as a good source of protein, along with lean meat, poultry, beans and nuts. Nutrition experts say the new study is unlikely to change that advice.
So what’s new about this study? Here’s what CNN had to say about it:
The researchers examined data from six US study groups including more than 29,000 people followed for 17½ years on average. Over the follow-up period, a total of 5,400 cardiovascular events occurred, including 1,302 fatal and nonfatal strokes, 1,897 incidents of fatal and nonfatal heart failure and 113 other heart disease deaths. An additional 6,132 participants died of other causes.
Consuming an additional 300 milligrams of dietary cholesterol per day was associated with a 3.2% higher risk of heart disease and a 4.4% higher risk of early death, Zhong’s analysis of the data showed. And each additional half an egg consumed per day was associated with a 1.1% higher risk of cardiovascular disease and 1.9% higher risk of early death due to any cause, the researchers found.
Here’s where things get a bit interesting and more complicated. News sources are not consistent in their reporting of these results. The New York Times said this about the results:
The researchers calculated that those who ate 300 milligrams of cholesterol daily — about 1 ½ eggs — were 17 percent more likely to develop heart disease than whose who didn’t eat eggs.
So which is it? Eating 300mg of dietary cholesterol a day, or 300mg MORE of dietary cholesterol (than what?) a day is bad for me? I think the New York Times got it wrong this time.
I went to the original paper, which is long (15 pages, a lot for a medical journal), and has loads of tables with loads of data. In the discussion section (which is always what you want to read when tackling these technical papers), they raise a bunch of issues that bear directly on how to interpret their results, how to understand their results in contrast with eggs-good research results, and what they think is really going on with respect to eggs, dietary cholesterol consumption, and mortality risk:
previous meta-studies have been all over the place, finding positive, negative and no correlations between more frequent (more than one a day) egg consumption and risks of death from various diseases.
Apparently egg consumption has been associated with low physical activity, smoking, and “unhealthy dietary patterns” (according to the paper). So it’s hard to separate egg consumption effects from these other effects.
The associations found between egg consumption and mortality risk were modest, but statistically significant.
Researchers claim a dose-response effect of egg consumption, which means the more eggs you eat, the higher the effect.
Their discussion raised some questions for me:
Do the researchers think there is a “safe/normal” intake amount of dietary cholesterol? They say the mean intake in the US is 289mg/day, and that taking in 300mg more per day (which would be 1.5 eggs, including half the extra yolk) increases all-cause mortality. But what is their nutritional goal here?
When researchers say egg consumption should be reduced, what do they have in mind for its substitutes? Eggs are a big source of animal protein, and lots of other sources have more saturated fat, which has its own scary back story.
As always, I am wondering to what extent statistical or research significance translates to clinical or medical significance?
All eating happens in social and cultural and economic contexts– if you ask people to reduce eating X, will substituting Y make things better or worse?
What do you think, dear readers? Is this new egg news throwing a monkey wrench into your brunch plans? Are you vegetarian or vegan and don’t care? Is this a reason to increase our vegetarian or vegan eating? Are you inclined to just turn the page and dismiss the nutritional research as a mass of confusion? Should we short-sell egg futures (I don’t know what that means, exactly, but I think it sounds business-y)? I’d love to hear from you.