Can you tell us a little bit about yourself?
Well my career has come from different directions. I started first as a research scientist; I spent a lot of my career in medical research, mostly laboratory-based. But I found I was much more interested in the role of nutrition in disease prevention, and also the role of nutrition in sports performance. And I was reading a lot of papers in these areas, rather than actually doing the core research that I was employed to do and my career was focused upon. It led me into exploring what sort of careers were open to me, and the word “dietetics” kept coming up quite a bit. So, I bit the bullet and retrained as a dietitian, and for the last 16 or so years, I’ve been in the university system, marrying together my research background in medical research, combined with the practical aspects of nutrition.
So, all of that is going through my mind when I communicate about nutrition. It’s underpinned by a strong foundation in scientific research, but also putting it into practical terms for what it means for people. And that’s how I communicate through my social media channels and through the media. Because you can have all the wonderful science in the world behind you, but what does it mean for somebody? And because we’re talking about nutrition, it is something that’s inherently personal to all of us because we all eat. So, that’s what I do and what I intend to keep doing in the future, because I’ve been driven by the career journey I’ve had so far.
What is your take on the recent study linking a gluten-free diet to an increased risk of type-2 diabetes?
This is a nice example of how the media loves a headline for the day, and this was the story du jour. It came from a conference abstract from the American Heart Association, so it wasn’t a paper, it was a conference abstract. So it wasn’t peer reviewed to the level of a journal article. Really what it showed was that at an observational level, people that have less gluten in their diets are at higher risk of developing type 2 diabetes. Now, what it was likely a marker for, if we take it that the results were reasonably valid, that a low intake of gluten was probably a marker for a low intake of whole grain foods, and we know that whole grain foods are protective against a whole range of diseases and type 2 diabetes would be one of them. But of course with this research though, as with a lot of things in nutrition; it’s imperfect research. We’re using long-term cohort studies that run for some decades where we need to use food frequency questionnaires to determine what somebody ate ten, twenty or thirty years ago.
A lot of what we think we know today is based upon imprecise measurements; we don’t have the perfect tools, but we try and do the best we can with what’s available to us and interpret the results in the context of the greater dietary themes. When I look at decades of research, those themes always point in the same direction. That is that a diet that’s mostly plant-based, has minimally processed foods in it, does not include a lot of animal foods, in particular red meat, and doesn’t have a lot added sugar is consistently linked with good long-term health. So studies like this type 2 diabetes one and gluten intake was probably just a marker for people having a poorer diet overall at the same time of having less gluten. So what does it mean for everybody else that’s on the gluten-free bandwagon? Probably if you’re going to cut out gluten foods in your diet, substitute them with similar whole grain foods that give you just as good nutrients.
And this is where a dietitian comes in to talk about the practical aspects, and if somebody wants to jump on the gluten-free bandwagon, I wouldn’t be a naysayer and say “Don’t do it.” If they’re set on doing it, then provide some practical food swap advice such as instead of having wheat and other gluten-containing foods, have things like rice and quinoa and so on that can be just as beneficial, but won’t contain the gluten, and really won’t affect their diet quality overall.
I’ve heard you’re a fan of Google Trends. What are the most surprising nutrition things you have seen on Google Trends?
Google Trends is one of my favourite tools because with a lot of things happening today that we want to know, we have no way in solid research of finding it out. It takes many, many years before we get good quality consumer data appearing in the literature, whereas Google Trends keeps its finger on the pulse of what’s happening today, and you can track changes in trends back as far as 2004.
One of the things about Google Trends is it really shows quite clearly how things come and go in nutrition. And the paleo diet is certainly on the wane. Low carb diets have been big before and they’re sort of big at the moment. Will they keep growing bigger and bigger? Who knows. But things like the Mediterranean diet or a vegetarian diet; if you put them in Google trends, you pretty much get a flat line. So these are ways of eating that really aren’t fads in terms of people jumping on and off bandwagons. People generally adopt them if they find it works for them, if not, they move onto something else; but it doesn’t capture the public’s imagination like some of the big fad diets that work for a short period of time and then people move onto something else.
I’m yet to determine how to use Google trends to predict what the next future trend is going to be. If I found such a way of doing it, I probably would be a very rich person because I would get in first and write the book and sell the products and flog the hell out of whatever trend that’s going to be in the future. But I’m happy to sit here and watch and give commentary about what’s happening now rather than try and drive the trends myself, because overall, the key messages as dietitians that we’ve always had hasn’t changed that much. It’s how we communicate them that we need to be doing better, and we can learn a bit from the wellness warriors and how they communicate their fads and sell their books and their green smoothies and so on.
Do you believe that dietitians should be more open to low carb diets for people with insulin resistance depending on the individual?
My answer is absolutely, yes. As evidence grows, we should change our viewpoint over time. And with low carbohydrate diets, while they are not a cure-all as being promoted on social media with anecdotes, the evidence shows that they can be just as effective, and perhaps more effective in some people especially with type 2 diabetes, than traditional dietary approaches. So a lower carbohydrate diet is now supported by the American Diabetes Association in their 2014 revision of their recommendations, which now don’t recommend any level of carbohydrate or fat—it should be completely individualised.
In January of this year, the DAA have actually changed their recommendations about low carb diets, and they at acknowledge these diets can be used in the appropriate situation under support and guidance by a dietitian. They don’t work for everybody though. Even in some of the clinical trials with low carb diets, not everybody sees the HbA1C plummeting falling. And people on an alternative diet can do just as well, but there might be a slight edge to low carb diets over traditional diets to manage type 2 diabetes, particularly in the initial stages when weight loss is occurring.
So I would say to dietitians to be open to considering them more, to be aware that nutritional quality will always trump the macronutrients, so focusing on that first and really as dietitians, that’s what we do anyway. And have them as one tool in your arsenal that you could use with a patient, particularly a patient that is more receptive to trialling one of these sorts of approaches.
If you could change the Australian Dietary Guidelines, what are some of the changes you would make?
I would make them less prescriptive in some ways. They may seem quite general overall when we talk about what they actually say: eating mostly plant-based foods, not having a lot of added sugar, eating plenty of fruit and vegetables and so on; things that are not so controversial. If you dig into them, they do have a macronutrient range that they generally advise people to fit within. Acknowledging that people do better or worse on particular dietary approaches would be a positive step. So, acknowledging that we are all very different, we all have different food habits and taste and preferences. To make the Australian dietary guidelines a little bit less prescriptive in some ways about the number of serving sizes and perhaps a focus on carbohydrate foods a bit less, and to be a bit more inclusive of different approaches whilst still maintaining the overall theme of what they’re recommending, and that’s mostly a minimally-processed, plant-based diet.
If you look at what Nutrition Australia have done in the last two years when they revised their food pyramid, they actually put fruits and vegetables at the base of their pyramid and then grains second. Doing this acknowledges that quantity-wise, in this land now of over-abundance of food, that perhaps less of a focus on the carbohydrate foods and more on the non-starchy vegetables would be a better way to go. So really that’s a tweaking of recommendations to acknowledge that different diets can perform equally well for different people, and we’ve still got some major chronic disease issues in Australia, so I think we need to look at our dietary guidelines to start with. But of course, acknowledging that very few people follow them in the first place. So really sexing the message up a little bit would be just as equally important.
Do you see nutrigenomics and the gut microbiome as a future for dietitians?
Nutrigenomics is yet to hit the big time. I would think we’re about 20 or 30 years away from really having the ability to prescribe diets for the majority of people based upon their genome. But the gut microbiome is probably a different matter. There was a study published last year that received worldwide attention where Israeli researchers quite accurately predicted the glycaemic response to food of a person based upon a variety of inputs such as anthropometry, medical conditions and so on; but they also factored in the gut microbiome. So the gut microbiome I would see as a potential tool for dietitians to be using because of the emerging evidence for how much it influences our mental health as well as our body weight. And yet, when you look at the gut microbiome research, it’s really pointing in the same direction that most good food nutrition messages are pointing to anyway; and that’s eating lots of plant-based foods and lots of fibre.
The gut microbiome may be just a different way of tweaking advice for a person to personalise them, yet at the same end, you’ll actually be giving broad dietary advice that you’d be giving in the past. You’re just optimising based upon particular foods that may suit that person more based upon their microbiome. So perhaps in the future, we will all retrain as microbiologists and have our lab coats on and play with our petri dishes, and take that into our consulting room with our patients.
I’ve heard a lot about coconut oil and know that most dietitians point to the saturated fat content is an issue. Do you have an opinion on the effects of coconut oil on brain function?
Coconut oil is well over-hyped on the Internet. There’s a little bit of research that coconut oil may have a small therapeutic benefit in Parkinson’s disease, but really, we need a few more studies to see how strong a benefit there is. It is not a cure-all. If you put the word coconut oil and Parkinson’s disease in Google search, you’ll get all sorts of woo sites pop up promoting it as a cure for Parkinson’s disease; it certainly is not. But it may have effect on brain function in this perspective.
So we’ll see more research emerging about coconut oil, or as a proxy the medium-chain triglycerides which there are lots of in coconut oil. But the internet is well in advance of what the research is saying at the moment, and I’m not advocating at all that anyone should be having spoonfuls of the stuff every day to lose weight and improve their brain function.
Final question: you have all the knowledge, but what do you do with your own diet?
I don’t do anything special. I try and eat five servings of vegetables and two pieces of fruit every day. I get the fruit pretty easily, but I’m not always doing the vegetables. I also acknowledge though that in the scheme of health, diet is just one aspect; there’s lots of other things you can do for your health: not smoking, being very active, not drinking much and so on. And trying to eat as best that you can, fitting in with enjoying food as well. I’m also a marathon runner, so I pretty much eat what I like because I’ll burn it off when I run 30 or 40km on the weekend on my training. I don’t have some perfect wonderful diet. I certainly wouldn’t consider Instagramming the food I eat that often, but I acknowledge that food is to be enjoyed. You can have a bit of everything, but not too much of anything, and that’s the approach that I have with my own eating. It’s the same approach I have when I communicate my messages to other people to acknowledge they’ve got their own personal preferences. I don’t like to prescribe things. Just to give some overall guidelines about what’s the best way to be eating for health that works for them and debunk some of the crazy along the way.
Dr Tim Crowe is a career research scientist and educator in the area of nutrition. He holds a BSc(Hons), MNutrDiet and a PhD. He is also a credentialed Advanced Accredited Practising Dietitian with the Dietitians Association of Australia. To learn more about Tim you can check out his website Thinking Nutrition or like his page on Facebook.