fitness · nutrition

The continuing carb-troversy: was Goldilocks right?

Prominent among the Questions Of Our Time is this one: just how many/much carbs should I have in my diet? Is it best to eat low-carb, like the Atkins Diet? Or stick to kinder/gentler/higher-fiber carbs like the South Beach Diet? Or close-to-no carbs like the Whole 30 Diet? What about higher carb diets? Don’t people use those during high-intensity athletic activity? Or is there some happy medium, some just-right amount of carbs that will optimize on my health, longevity, weight, complexion, etc.? Just where is Goldilocks when we need her?

Goldilocks enjoying some soup in a medium bowl, hopefully with quinoa instead of white rice or pasta if she knows what's good for her... :-)
Goldilocks enjoying some soup in a medium bowl, hopefully with quinoa instead of white rice or pasta if she knows what’s good for her… 🙂

A new study in the Lancet is now taking sides with Goldilocks, publishing a study saying that a moderate carb diet is in fact the “just right” amount for optimum longevity. Here’s a summary from the Live Science news website:

The study, which involved more than 15,000 Americans who were tracked for a quarter of a century, found that those who ate a low-carb diet (with less than 40 percent of daily calories coming from carbs) or a high-carb diet (with more than 70 percent of daily calories coming from carbs) were more likely to die during the study period, compared with those who ate a moderate-carb diet, with about 50 to 55 percent of their calories coming from carbs.

For example, based on the findings, the researchers estimated that from age 50, people who consumed a moderate-carb diet would have a life expectancy that was about four years longer than those who consumed a very low-carb diet (with an average life expectancy of 83 years for moderate-carb eaters versus 79 years for very low-carb eaters).

Another of their key findings was when they investigated different types of low-carb diets:  ones with a lot of animal-sourced foods, versus plant-sourced foods. Here’s what the Live Science article has to say about the study:

…the analysis also found that, with low-carb diets, what mattered was the source of proteins and fats. Diets that involved replacing carbs with proteins and fats from animal sources, including beef, lamb, pork, chicken and cheese, were linked with a greater risk of death. In contrast, diets that involved replacing carbs with proteins and fats from plant sources, such as vegetables, legumes and nuts, were tied to a lower risk of death.

So is the take-away message that we should all aim for moderate (50ish%) of carb intake in our diets to maximize lifespan?

Not exactly.  As I say all the time in blog posts, science is complicated. Just ask these women– they can explain it to us.

African women scientists in a lab, going over procedures.
African women scientists in a lab, going over procedures.

You might be wondering– what about higher-carb diets? They aren’t prominent these days in the popular diet industry, but they are an option and serve a number of nutritional purposes. Also, lots of cultures outside of North America and Europe eat high-carb diets Does the study show that those lead to earlier death, too?

Well,  it depends partly on where you live and what you eat. The primary study participants used in the Lancet article were from the US. For them, the results were a U-shaped curve, which means that the highest risk was at either end— low carb or high carb.  Here it is:

U-shaped risk curve of carb dietary intake, with highest risks at low and high end of card intake (<40%, >70%).
U-shaped risk curve of carb dietary intake, with highest risks at low and high end of card intake (<40%, >70%).

But take a look at the right side of the U– it doesn’t rise as high as the left side does.  That means that the riskiness of high-carb diets in this study is not as big as the riskiness of the low-carb diets. (By riskiness, I mean all-cause mortality risk, but you get the idea here). So, their results suggest that higher-carb diets aren’t as risky (I know, that word again, but humor me) as the low-carb diets.

Later in the Lancet article there is another set of U-shaped curves, with the second one being an amalgamation of many other studies that these researchers analyzed.  These other studies were done in many parts of the world, including places where people eat lots of higher-carb diets with foods like white rice or other simple (vs. complex) carbs. There we see a greater rise in mortality risk as carb intake increases. Complexity enters again, this time at the level of the carbs themselves.  People who eat higher-carb diets but with more complex carbs may (this is still a bit tentative) may mitigate their mortality risk of a higher-carb diet.

Finally, there’s been a good bit of critique and response, of which you readers might be interested in two points:

Point one: There are SO MANY features of our dietary intake that interact with each other, our environment, our genetics and microbiome, etc., that it’s very hard to separate out and identify the effects of one variable on health and mortality. One commentary (in the Lancet) said this:

…this approach should be complemented by large and long-term clinical trials investigating the effects of different dietary patterns (constructed from information about the effects of individual nutrients and foods), because the effect of individual nutrients is likely to be modest.

So we aren’t going to get solid clinical recommendations for people based on the effects of shifting carbs alone.

Point two: The researchers’ findings only tracked mortality risk shifts.  They didn’t track them to any biomarkers or clinically observable features that we could identify that would help in offering medical advice to people. Of course, they weren’t trying to do the latter, but without the latter, the information isn’t so helpful for real-life medicine.

The commentary concluded with this:

When coherent information emerges from different approaches and is replicated, this will form a sound basis for robust public health recommendations.

Or, in other words, “yeah yeah.  Get back to me when you have something that will be useful for clinicians moving forward in trying to identify health issues connected to dietary carb intake, or a more complex but robust view on these interactions with health.”

Here’s the final-final point.  Let’s suppose that Goldilocks is right– moderation in carbs is the just-right path. What do we mean by “moderate intake”? 40–70% is a very big range, and loads of other factors can make a big difference in effects on health, mortality, etc.

If we’re supposed to take nutritional advice really seriously, need more than “just-right” to go on.  Luckily, other studies are working on exactly that. Stay tuned for the latest…

 

 

 

 

 

fitness · nutrition

Food: yes. Vitamin supplements: mostly no.

There’s been a lot of vitamin supplement research in the news in the past year. In mid-December, a pretty pointed editorial came out in the Annals of Internal Medicine. Here’s what it said:

Enough is enough: stop wasting money on vitamin and mineral supplements.
Enough is enough: stop wasting money on vitamin and mineral supplements.

I find this a refreshing change from more carefully couched medical speak like “blah blah new medicine blah blah no statistically significant effect on blah blah under blah blah conditions blah.” Basically, they are saying this: do not buy vitamins. They don’t reduce your risk of dying from heart attack, your risk of cognitive decline, and some of them increase your risk of various bad health outcomes.

Now fast-forward to today: a new study has come out, and researchers found that some vitamins do in fact increase risk of death.  That sounds bad (because it is). Here’s an excerpt from an article on the study:

Researchers at the University of Toronto conducted a meta-analysis of all published randomised controlled trials that looked at the effects of vitamin and antioxidant supplements on the risk of heart disease and stroke.

They found the most commonly used supplements – multivitamins, vitamin D, calcium and vitamin C – provided “no consistent benefit” for the prevention of cardiovascular disease or stroke. Folic acid alone and B-complex vitamins, which contained folic acid, did show a reduction in stroke.

However, niacin (vitamin B3) and antioxidants (vitamins A, C and E) were associated with an increased risk of all causes of death, according to the findings published in the Journal of The American College of Cardiology.

One researcher was quoted in the article saying that, while it’s great that we no longer have problems like scurvy in the population, that doesn’t mean that people in general should take a multivitamin.  What should we do, then?

Eat food. That’s it.

For more cool info on vitamins, how people keep taking them even though they don’t need them, and some speculation about why food is better than vitamins (short answer: we don’t really know), look at this interesting NY Times article.

And if we follow this advice, we’ll have more disposable income, too, (in addition to not increasing our chances of dying).

Happy Thursday!

 

fitness · nutrition

Fake egg news? More on the eggs-good/eggs-bad controversy

Just to be clear, this post is not on news about fake eggs.  There’s a whole internet discussion about them (which is not well-substantiated).  I don’t mean the standard brightly colored Easter eggs that look like this:

Easter eggs painted in bright colors, with dots and swirls and lined patterns. Pretty...
Easter eggs painted in bright colors, with dots and swirls and lined patterns. Pretty…

I mean manufactured ersatz eggs, being sold as actual eggs.  The internet discussion suggests they’re being made in China from many artificial ingredients, one of which is called “magic water” (which may just be salt water– not clear).  Read all about it here.

But I digress. What’s been in the real news recently is a Chinese study investigating associations between egg consumption and risk of cardiovascular disease.  Their published conclusion was this:

Among Chinese adults, a moderate level of egg consumption (up to <1 egg/day) was significantly associated with lower risk of CVD, largely independent of other risk factors.

Of course, mainstream news roared into gear, cranking out the following headlines:

Even the medical newsletter BMJ (British Medical Journal) Heart swallowed the story whole, reporting on the eggs-good turn of events here.

There’s a lot to criticize here, both about the new eggs-good study and the uncritical reportage, including those (like BMJ Heart) who ought to know better.  In brief:

  • the study is observational, so it can’t establish cause-and-effect;
  • it relies on food frequency questionnaires, which are notoriously unreliable (who remembers what they had for breakfast last Wednesday? Anyone? Anyone?)
  • there were loads of confounders in the study– that is, other features of groups of participants which could account for some/most/all of the effects they say they observed. Read more about all of these here.

But: what about the eggs? Are they good for us or bad for us?

I have three answers to this question:

  1. Woman shrugging her shoulders, indicating "I have no idea".
    I have no idea.

    2.

    A person standing in a field on a haybale, with the words "in the end it's not my call".
    In the end, it’s not my call.

    3.

    an open carton of a dozen eggs, with the words--You get to decide what counts as "good" food to you; and then whether and when and how and how much to eat of it.
    You get to decide what counts as “good” food to you; and then whether and when and how and how much to eat of it.

     

For more on the eggs-good/eggs-bad affair, you can read my 2016 blog post on it here.  We have also posted a lot about the notions of “good” and “bad foods.  Here a, but just google it and you’ll find we have a lot to say.  However, the TL:DR version is this: there aren’t any “good” or “bad” foods. There may not even be any “good for you” or “bad for you” foods.  There’s food, and then there are all of our views and concerns, and needs and constraints, and preferences, etc. about the food.

What do you think when you read headlines like “[insert food x here] is now shown to [insert prevent or cause] [insert bad health thing]?  Are you inclined to change your eating habits based on the new news that food X is now “good for you” or now “bad for you”? We’d love to hear from you.

 

 

 

food · nutrition · sports nutrition · weight lifting

Want to keep muscle after 40?: Eat all the protein and lift all the things

A cricket protein bar
A cricket protein bar

Researchers at nearby MacMaster University set out to do a meta analysis in search of an answer to the question of whether protein consumption made a difference to ordinary adults over 40 who set out to gain muscle.

What’s nice, from this blog’s perspective, about the studies is that many of them included women.

Gretchen Reynolds wrote about their research in the New York Times.

Lift Weights, Eat More Protein, Especially if You’re Over 40

“They wound up with 49 high-quality past experiments that had studied a total of 1,863 people, including men and women, young and old, and experienced weight trainers as well as novices. The sources of the protein in the different studies had varied, as had the amounts and the times of day when people had downed them.

To answer the simplest question of whether taking in more protein during weight training led to larger increases in muscle size and strength, the researchers added all of the results together.And the answer was a resounding yes. Men and women who ate more protein while weight training did develop larger, stronger muscles than those who did not.”

How much protein? 1.6 grams per day per kilo of bodyweight. That’s well over the recommended daily amount of protein.

When? It didn’t matter when in the day people are the extra protein. So you don’t need to fuss about before or after workout or other special timing.

What kind of protein? That didn’t matter either. You can eat it in the form of animal protein or vegan protein. You can drink protein shakes. It’s all good.

See the scientific article here.

I haven’t tried the cricket protein bar just yet.

Fit Feminists Answer · nutrition

You Ask, Fit Feminists Answer: Do you have to start eating more food if you exercise and get muscles?

This is the fourth in a new series where we answer readers’ questions. If you have questions send them our way, using the “contact us” form on the left hand side of the blog. I’ll forward them to the appropriate blogger. We’re not experts by any means but we do have a wealth of real world experience with many, many physical activities.

Cate: I think the feminist answer is “you don’t HAVE TO do anything” 😉

Christine: My immediate (non-expert) response is that you may find that building muscle leaves you feeling hungrier. If it does, you may want to change what/when/how much you eat.
The goal would be to ensure that you have the energy you need so your body can do what you need it to. Eat in whatever way serves that goal best, but please don’t get caught up in the ‘shoulds’ of eating.

Kim: I agree with Christine: exercise and muscle-building generally takes more energy than you’d otherwise expend (if you are doing it correctly, it will tire you out and make you hungry), which means your body needs fuel to recharge and rebuild. Listening to your body here is a good idea, but at the same time my own experience has been that I sometimes over-eat when I’m fatigued and really hungry from exercise. So listening to your body when it says it’s hungry is good, but so is listening to it when it’s full (even if you might not immediately think you could or should be full yet). I’d also say that shifting or beginning an exercise routine is a good time to have a look at what you’re eating, and to ask yourself if you’re eating the best things to help your body recharge well and build muscle. If you’re not sure, it’s a good idea to do consult someone about nutrition choices, and about the best choices you can make given all of your lifestyle factors. (There’s no one easy solution or plan.) But finally: yes, eating more will happen, and yes, that is a proper, good thing!

Tracy: I think the short answer is “no,” you don’t have to eat more food but sometimes when people start working out seriously they start to think of food differently, as a way of fueling their workouts for optimum performance. It’s also often recommended (though this doesn’t make it a “have to”) that people follow a resistance training session with a protein rich meal.

Sam: I think it depends on what you’re doing. Cyclists need to eat while riding and often struggle with consuming enough calories on the bike. After riding you might be ravenous but you don’t need to eat as much as you might think. It takes awhile to work this stuff out. Ditto with what you eat. Experiment. This stuff varies between people so figure out what’s best for you.

Okay, blog community, over to you… What’s your answer?

Donuts covered in fruit slices
Photo by Brooke Lark on Unsplash
fitness · nutrition

Meat vs. veg: when headlines can be misleading (or actually not true)

A couple of weeks ago, a new study came out, comparing forms of vegetarian diets with forms of meat-eating diets; the study itself is found here.  Probably all readers of this blog are automatically a little skeptical when they see a splashy headline with new, strong advice that goes against the prevailing wisdom in fields of health and nutrition.  Not that the so-called “prevailing wisdom” is always wise, or even prevailing– there’s lots of dissent and several conflicting theories about nutrition and health.

However, in the case the comparative benefits of vegetarian diets, compared with meat-eating ones, there is prevailing wisdom:  vegetarian diets are generally better for us on multiple health and nutrition fronts.

Just to provide one (of hundreds) of standard reports that support the health benefits of vegetarian diets, check out this World Health Organization report from the International Agency for research on cancer.  Here’s the bit that gets at the meat of the matter:

After thoroughly reviewing the accumulated scientific literature, a Working Group of 22 experts from 10 countries convened by the IARC Monographs Programme classified the consumption of red meat as probably carcinogenic to humans (Group 2A), based on limited evidence that the consumption of red meat causes cancer in humans and strong mechanistic evidence supporting a carcinogenic effect. This association was observed mainly for colorectal cancer, but associations were also seen for pancreatic cancer and prostate cancer.

So, meat is probably carcinogenic to humans.  Well, that’s not good. Of course, real science and real science policy are nuanced, so here’s their summary recommendation:

These findings further support current public health recommendations to limit intake of meat,” says Dr Christopher Wild, Director of IARC. “At the same time, red meat has nutritional value. Therefore, these results are important in enabling governments and international regulatory agencies to conduct risk assessments, in order to balance the risks and benefits of eating red meat and processed meat and to provide the best possible dietary recommendations.

This is not really news, but of course good to hear from a knowledgeable and trustworthy source.

But then comes this new study, which was reported like this:

Caption: New study shows a vegetarian diet is associated with poorer health
Caption: New study shows a vegetarian diet is associated with poorer health

 

What?  How could this be?  Here’s what the news report said:

Interestingly, while there were positive benefits associated with vegetarianism, the group concludes the following: 

Overall, our findings reveal that vegetarians report poorer health, follow medical treatment more frequently, have worse preventive health care practices, and have a lower quality of life… Our results have shown that vegetarians report chronic conditions and poorer subjective health more frequently.

They also discovered “significantly higher” incidences of cancer in vegetarians, as well as increased rates of anxiety disorder and depression, although they note that this is inconsistent with other research. They did point out another study which shows an increased risk of mental disorders in vegetarians. In general, vegetarians suffer from more chronic conditions and take more medication than even occasional meat eaters. 

Wait a minute.  Did the study REALLY show all this?

No.  Not if you’re asking me. Or, rather, not if you’re asking some friends of mine who are much more familiar with the research on vegetarianism than I am (thanks, Angus and Bob!)  One sent me a laundry list of problems with the original Austrian study.  Here’s his list:

Problems with this study include:

  • Small sample
  • Questionnaire-based
  • Lack of distinction between vegetarians for ideological reasons (e.g. animal suffering and environmental reasons) v those that may be vegetarian on medical advice or due to self-treatment due to pre-existing health conditions
  • Many data points are subjective (self-declared)
  • They make some weird claims (a Veg diet is ‘related to’ less frequent alcohol use)
  • There are a huge number of confounders given the association of other factors related to veggie diets – I don’t think they are able to fully account for these – especially given sample size.

The other friend sent me these comments:

  • First, there is — as the authors suggest — evidence pointing the other direction with respect to each of their specific conclusions. So that should adjust our confidence level a bit.
  • Second, it’s pretty plausible that because foods aren’t fortified in a way that assumes that people are going to eat vegetarian or vegan, some less health-conscious vegetarians and vegans are going to suffer from nutritional deficits that will negatively impact their health. It isn’t clear how much of the effect this would explain, but it helps us think about the fact that there are political realities that are relevant to these nutritional studies. 
  • Third, the authors don’t consider the fact that some people may be switching to vegetarian vegan diets for health reasons — that is, because they have some health issue they are trying to address via dietary change, which suggests that they may well be less healthy than the average member of the population to begin with.
  • Fourth, and most importantly, the authors of the study lump together strict vegans, vegetarians, and pescatarians. Given that many vegetarians and pescatarians eat diets that are still fairly heavy in animal products, it wouldn’t be surprising if any health benefits of a strict vegan diet were invisible in the data.
All of us immediately thought that this was an underpowered study whose results were questionable in large part because of the odd (to us) was the researchers chose to divide up the study groups:  vegetarians; sometime meat-eaters who eat lots of fruits/veggies; regular meat-eaters whose fruit/veggie intake we don’t know about; meat eaters who (probably, but who knows) eat lots of meat.
And as for the results, all of us know that there are lots of confounders here— that is, there are lots of explanations for the data that involve known factors that have nothing directly to do with meat/veg intake.
You may still be wondering:  what’s the most healthy way for me to eat?  Hmmm.  That’s a hard one, in fact too hard for any one study or even group of studies to answer.  We’re all working on eating in ways that seem healthy-to-us based on the best scientific evidence available, taking into account our constraints of taste, cooking abilities, time, money, culture, physical activity needs, ethical principles, etc.  No one has all the answers.  But I do have an answer to this question:  do we now have good reason to think that  vegetarian diets now associated with poorer health?
One word: NO.
One word: NO.

 

 

 

 

diets · fitness · food · health · nutrition

Why I’m glad I stopped worrying about sugar and other weird food obsessions

I had a funny exchange the other day on Facebook. There was a link about the dangers of the cheese powder in boxed mac and cheese. I commented on my friend’s post that when we can, we should rely on whole foods to make mac and cheese. Being an American, my friend thought I meant the food chain Whole Foods, which is not so cheekily known as Whole PayCheque for the high cost of it items.

Image: White bowl with pasta noodles, red tomatoes, and green basil.
Not macaroni and cheese, but my favourite feta, basil and tomato pasta supper.

Nonetheless we had a good chat about how expensive it can be to eat whole, unprocessed foods, and that led us to a whole other thread about clean eating, healthy eating, good foods, bad foods, cheat meals, etc. We weren’t actually talking about our approach to nutrition but the way the words we use to talk about food get co-opted by all kinds of agendas. It’s quite easy to have all sorts of “isms” and attitudes creep in, altering our meaning and twisting our understanding of food as fuel in our lives and how we relate to it in different contexts.

That same day SamB brought my attention to this article about Anthony Warner, described by the Guardian as “(the Angry Chef) who is on a mission to confront the ‘alternative facts’ surrounding nutritional fads and myths.”  Warner writes a blog on food fads, and he doesn’t hold back. He’s now written a book called The Angry Chef: Bad Science and the Truth About Healthy Eating, and I ‘m adding it to my reading list.

That’s because when you start a fitness program, there’s all manner of advice on how to eat, what to eat, and why the one true way (insert your favourite fad — howsoever you define it —  diet here) will be all that you need. Even if your goal is not weight loss, there’s all kinds of recommendations (cough, cough, rules!) on how to eat to train.

Heck, you don’t even have to be training to get food advice. I’m convinced all you have to be is female and not meet someone’s pre-conceived notion of how female should look, for the advice to come pouring in, accompanied by a generous helping of side eye finished with a soupcon of shade, if the advisor deems your food choices not to meet their definition of “healthy” eating.

What appealed to me about Warner is his evidence-based approach. In the article he says: “A lot of the clean-eating people, I just think they have a broken relationship with the truth. (…) They’re selling something that is impossible to justify in the context of evidence-based medicine.” I like science and research and critical thinking. Sadly, there’s too little of it when it comes to talking about food and part of it goes back to the agendas behind the particular terms used.

Warner says our fascination with fads or trends in food and eating is connected with our innate need for certainty. He explains it this way: “We really want to be able to say: ‘Is coffee good or bad for us?’ Well, it’s not good or bad for you, it just is. And we have to accept that; that’s what science says. So your brain goes, ‘I don’t like that level of uncertainty.’ Certainty is really appealing for a lot of people and that’s what a lot of these people are selling – certainly at the darker end.”

And he’s right. The people who have preached to me about gluten free diets when they aren’t celiac are utterly convinced of the rightness of their belief that going gluten-free cured their ills. Equally certain are the people who now look upon sugar with the same fear and revulsion we bring to edible oil masquerading as coffee creamer.

As I survey the speciality food shelves in my local shops, I’m enchanted by all of the interesting food stuffs and yet, truthfully, I am also challenged by how these same items are elevated in social media, on Instagram, and by celebrities to miracle food status. Warner, who lives in the UK and works for a food manufacturer is clear about the limitations food makers face when it comes to making claims about food: “If I made a food product and I wanted to say ‘it detoxes you’, I absolutely couldn’t. There are really clear laws: I can’t say it in the advertising, I can’t say it on the pack, I can’t make any sort of claim that isn’t hugely backed in evidence. But if I wrote a recipe book, I can say what I want.”

If you have been wondering how Gwyneth Paltrow can make pots of money selling her fans coconut oil as a mouthwash and wasp’s nests as a vaginal cleanser, there’s your answer. The trick is to stop engaging in magical thinking when it comes to food and applying some common sense. Warner’s advice: “eat a sensible and varied diet, not too much nor too little. If you have junk food every so often, don’t feel guilty; if you’re going full Morgan Spurlock, you’re probably overdoing it. Eat fish, especially oily ones such as salmon and mackerel, when you can. Don’t consume too much sugar, but equally don’t believe people who tell you it’s “toxic” and has “no nutritional value.”

Or you can go the Reader’s Digest version and follow Michael Pollan’s advice: “Eat food. Not too much. Mostly plants.”

Excuse me now, as I forage in the fridge for the leftover maple syrup glazed salmon.

— Martha is a writer and powerlifter in training exploring a whole new world of food as fuel.