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It's quite alarming that in this metabolic syndrome epidemic, there is a divergence of opinion from health professionals regarding an appropriate diet.

There is a growing proponent of supporters for a low carb high-fat (LCHF) diet as described in dietdoctor.com, and supported by physicians like Canadian nephrologist and LCHF evangelist Dr. Jason Fung. These proponents argue that the low-fat craze was initiated from poor studies and continued via sugar lobbyists and good ol' medical inertia. An example of a poor landmark study was via physiologist Dr. Ancel Keys who linked heart disease with the consumption of fats by comparing the diets of americans and the brits to the japanese (while ignoring heart-healthy butter loving nations like france, and norway). He inevitably endorsed (and was covered on TIME magazine in 1964), a daily caloric profile of 70% carbs 15% fat: http://nypost.com/2016/12/20/how-butter-became-a-villain-and-why-its-actually-really-good-for-you/

These LCHF folks then argue that there is mounting evidence of the alternative (This source links 19 RCTs favouring LCHF for weight control and chronic disease: https://www.dietdoctor.com/low-carb/science).

On the otherhand, my senior attending staff (ie. conventional medical wisdom) and uptodate and other prolific medical resources would claim that there are huge merits to a low fat diet instead. On the uptodate article "Obesity in adults: Dietary therapy", it notes the merits of a LCHF diet; however, it ultimately argues that a low fat diet is atleast non-inferior to LCHF and cites studies that support that claim (studies that I don't personally find very compelling).

I'm a Canadian medical resident, and it required a substantial amount of digging and an understanding of medical literature for me to currently be in favour of LCHF. Imagine how challenging it is for our patients to be confident enough in their idea of an ideal diet in order to stick to it and develop meaningfully positive long-term outcomes.

What do you all think? LCHF FTW? Low-fat FTW?

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  • 5 weeks later...

My background is in nutrition and I can tell you that people tend to think too hard about it because they cling to the idea that there is an ideal diet for everything and everybody. This is not the case. Cutting out all carbs is not the answer and neither is eating a ton of carbs. Fat is not as bad as many say and neither are carbs, especially complex healthy carbs like found in oats, barley, lentils, beans, etc, etc. Seriously the best diet is one that is mostly plant based, with limited refined carbs (white flour, simple sugars), rich in mostly good fats (mono and polyunsaturates via fish and nuts, though some saturated fats in whole dairy is perfectly fine as well), moderate caffeine and alcohol (no more than 2 drink on any given day), limited processed/cured/smoked meats and moderate meat in general. Carbs should be relatively low GI like beans, lentils, chickpeas, barley, oats, etc. 

I know people want a simple answer in the vein of "Eat like this!" but the most rigorous evidence (limited to be honest in nutrition research for mostly monetary reasons), show a common sense moderate diet such as a Mediterranean-style or DASH-diet style (essentially like a described above) is best. This is also the style of diet that is much more realistic than trying to 'stick' with a partiicular set of foods or strict diet that is no healthier than a more moderate diet. 

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1 hour ago, gangliocytoma said:

Take a look at the benefits of a ketogenic diet. High fat no carb and can change people's lives (including those with metabolic syndrome).

The evidence for ketogenesis long-term is poor. The extremely restrictive diet required to get true ketogenesis is not possible to sustain long-term for the vast majority of people, and they tend to regain the weight after they begin to go back to their pre-keto diet, and some often regain more weight. Not to mention the long-term health implications of constant ketogenesis are unknown. 

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58 minutes ago, schmitty said:

The evidence for ketogenesis long-term is poor. The extremely restrictive diet required to get true ketogenesis is not possible to sustain long-term for the vast majority of people, and they tend to regain the weight after they begin to go back to their pre-keto diet, and some often regain more weight. Not to mention the long-term health implications of constant ketogenesis are unknown. 

I don't think it's overly restrictive, perhaps with modernization of society we've become too loose with carbohydrate consumption. And after being ketoadapted for a while you can get away with eating 50-100g of carbs and not getting kicked out of ketosis. The good thing about it is that once you're in ketosis craving for carbs is down next to zero, which makes it easier to stick to the diet.

From what I've seen, the long-term health implications of constant ketogenesis appear to be improved longevity ;).

As for the weight regain, from my understanding that happens with practically every diet. From what I've read, the current theory behind the yo-yo dieting and weight loss/regain has more to do with certain gut microbes inactivating certain flavonoids (or other prebiotics) making it harder a "good" population of microbes to be established. Once the person ends their caloric restriction the higher energy harvest abilities of the gut microbes still remains and the person gets flooded with additional macros regaining their weight very quickly. The study showed that nuking the gut with antibiotics before returning to normal diet prevented the weight relapse. Another thing they showed was that supplementing with large amounts of flavonoids over time helped give the beneficial microbes a foothold in the gut, stopping the weight regain. Here is the paper in case you were interested! https://www.nature.com/nature/journal/v540/n7634/full/nature20796.html

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The diets are indeed too restrictive for most people, hence why almost nobody can stick with an actual ketogenic diet ('low carb' is not ketogenic) which has been shown many times in large studies. As for long-term health impications, I think you may be confusing energy restriction, which has decent evidence in rodents and non-human primates to increase longevity, but litttle evidence in humans (obviously unethical and pretty well impossible to run such studies). 

And I am well aware of the burgeoning gut biome theory of controlling everything in your body, and while promising, is in very early stages with very low level evidence to support a role. Best we can do is show that different diets induce 'changes' in the gut microbiota, the sequalae of which are not known as the science is incredibly difficult to discern. 

I agree that yo-yo dieting is bad....hence why I explained above that adhering to a specific 'diet' long-term is futile for most and instead it is best to shift, even slowly to a moderate, common-sense lifestyle as I described above without worry that a particiular food or nutrient doesn't 'fit' with a particular named diet. This shift in ones lifestyle removes the idea of 'dieting' from the picture and thus it is impossible to 'yoyo'...it is simply how one eats. I'm not saying it is easy to shift into this behaviour and mindset, but when it happens, it is usually a meaningful long-term change. People just don't aim for this type of shift as it doesn't have the hype or hyperbole attached to it as named diets that promise to be the fix for all their dietary woes.  

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5 hours ago, schmitty said:

The diets are indeed too restrictive for most people, hence why almost nobody can stick with an actual ketogenic diet ('low carb' is not ketogenic) which has been shown many times in large studies. As for long-term health impications, I think you may be confusing energy restriction, which has decent evidence in rodents and non-human primates to increase longevity, but litttle evidence in humans (obviously unethical and pretty well impossible to run such studies). 

And I am well aware of the burgeoning gut biome theory of controlling everything in your body, and while promising, is in very early stages with very low level evidence to support a role. Best we can do is show that different diets induce 'changes' in the gut microbiota, the sequalae of which are not known as the science is incredibly difficult to discern. 

I agree that yo-yo dieting is bad....hence why I explained above that adhering to a specific 'diet' long-term is futile for most and instead it is best to shift, even slowly to a moderate, common-sense lifestyle as I described above without worry that a particiular food or nutrient doesn't 'fit' with a particular named diet. This shift in ones lifestyle removes the idea of 'dieting' from the picture and thus it is impossible to 'yoyo'...it is simply how one eats. I'm not saying it is easy to shift into this behaviour and mindset, but when it happens, it is usually a meaningful long-term change. People just don't aim for this type of shift as it doesn't have the hype or hyperbole attached to it as named diets that promise to be the fix for all their dietary woes.  

I know what a keto diet is :P  it's < 25g net carbs/day. What I'm saying is that once your body undergoes keto adaptation, you can increase your carbs a little bit (<50g/day) and not get knocked out of ketosis.  Obviously this needs to be done while still maintaining a high % of fat in the diet.

I'm not confusing ketosis with caloric restriction for longevity. They actually work in a similar way however (great review: http://onlinelibrary.wiley.com/doi/10.1002/iub.1627/full). 

The point in me explaining the utility of a ketogenic diet is based on the benefits for different disease states. You have an autoimmune disease? Ketones and ketosis are intrinsically anti-inflammatory (block nlpr3 inflammasome activation). Are you suffering from metabolic syndrome? Ketogenic diets have been shown to decrease adiposity, reverse non-alcoholic fatty liver, normalize blood glucose, reset leptin signalling, and more...There's evidence it can slow or even reverse cancer. So seems like its a pretty versatile diet.

Regarding the microbiome... my current research is in this field so I may be a little biased, but I'll try to stay objective. I don't think we're at very low levels of evidence. The fact is that the gut is central to our body and has the ability to promote cross-talk to all organ systems. Yes, most of the studies are done in animal models, but we're at the point where we can say "if I give a skinny mouse a focal transplant from a fat mouse, the skinny mouse will become fat". This has also been observed in humans receiving fecal microbial transplants to treat C. difficile. 

A paper recently published has shown that microbes and their interactions with receptors in the gut drive cerebral cavernous venous malformations! https://www.ncbi.nlm.nih.gov/labs/articles/28489816/ There is no way you can deny that it is super cool and opens up and entire overlooked aspect of human physiology.

You can take feces from humans with certain diseases, transplant them into a mouse, and within weeks, that mouse becomes a model of that disease. Not to mention, there is ongoing work deducing the mechanisms that take place to make all this happen

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That's cool and all, but all of that research is super basic-level (including everything in that review which ends in opinion) and I have read similar promising research on pretty well every other type of diet as well, DASH (best research), low GI, caloric restriction, pre/probiotic, high fat, low Carb, etc, etc, etc....no repeatable human, long-term studies have been done to suggest any of that is actually as beneficial as you make them out to be. 

More importantly, none of that research, though very interesting and worth pursuing, provides any useful practical means of providing dietary counselling like was asked by OP. 

 

 

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We don't consider the biodiversity argument in nutrition that we're all different genetically and metabolically. Our socioeconomic factors and general lifestyles contribute to health too. Everyone should be trial-and-erroring different diets to see what makes them (1) feel better, (2) reach appropriate health outcomes and (3) able to sustain this approach for life. From an Indian family, there is too much diabetes and HTN but they have no intention of changing their diets. Having adopted keto, my personal weight goals have been achieved and nearly all lab values have improved (particularly A1c, triglycerides and HDL/LDL) so it's entirely possible that we're more susceptible to insulin resistance and I'm thriving on this diet, whereas others may feel awful and do worse with LCHF (but thrive on vegan or a HCLF plan). 

The dilemma for me is going into clinical rotation next year where we cannot just give advice that has worked for us, it has to be guided by evidence. I do not entirely agree with all nutrition guidelines or research due to other factors (like difficulty of having accurate long-term studies in nutrition) and even interest groups influencing results or industries with their own agendas. General tips like eating whole food, portion control, more vegetables, drinking water/tea/coffee only, no trans fats or added sugar, etc. are universal but beyond that, it seems difficult to advise others. 

I agree with @gangliocytoma that we've become too loose on carb consumption and the very nature of diabetes and obesity stem from insulin resistance so changing status quo away from grains as a major part of our diet will take ages to reach. 6-8 servings of grain a day? Seriously? Especially when carbohydrates are the only macronutrient that is not essential. If the true healthy plate has 50% vegetables, 25% grains and 25% protein, how many plates does someone need to get 8 servings of grains? Max 3-4 a day would fit with this proportion. I don't want to say to completely cut it out (cause its unrealistic for vast majority) but I'm sure we can get away from sugar-loaded foods, refined flour, and push for whole grains that are actually whole grain (not the whole grain bread bs that we romanticize as the best option).

I hope for better research in the future but it's such a dilemma until then. Couldn't agree more that doctors don't know about nutrition cause we're not taught about it but I also feel no one really knows about nutrition. "Eat foods. Not too much. Mostly plants" would alleviate a lot of health issues and can be a simple mantra for all to use. Also, intermittent fasting has been shown to improve outcomes but never mentioned as a plausible option cause why would the food industry want people to cut out meals and I'm sure vested interests in the US would rather you be sick and pay more for healthcare than just focus on prevention. Prevention doesn't make the $$$ for healthcare. Ok I'm done.

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NO one really knows about nutrition?  Really?  Hello, registered dietitians are the experts in evidence-based nutrition.  If, as a doctor, you aren't referring your patients who need dietary advice to a registered dietitian, you aren't doing a very good job.

BTW, most registered dietitians think that Canada's Food Guide is useless, which is why we advise clients to follow the Healthy Plate, the Mediterranean Diet, or the DASH diet.  However, truly getting clients to be able to make dietary changes requires TIME, something most doctors don't have.  So refer to the RD, who has 30-60 minutes per visit with a patient.

RDs are the nutrition experts.  If you aren't making use of them and are trying to advise your patients yourself on nutrition, you are doing your patients a huge disservice.

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Sorry, I didn't mean it that way. I meant that nutrition evidence itself has shifted in so many directions that there is always research for and against everything else. Dietitians are the obvious experts in the field, but I'm worried that the evidence is not as clear as other fields where individual physiology, compliance to the diet, comorbidities and personal preference don't allow for clear conclusive evidence towards one dietary plan vs another. 

I'm very glad that RDs aren't going purely off the food guide. My experiences with RDs have been that they say they are taught to champion the food guide so that made me iffy. Much more knowledgable than any other professional in nutrition and dietary science but the system itself does not support their work by providing a terrible food guide or pushing society towards unhealthy behaviors/options.

Again, considering how vastly unique everyone's approach to nutrition is, there have also been differences between dietitians on the correct way to manage patients. Some may be strong advocates for whole foods plant based or LCHF or Mediterranean or DASH. They know when to implement each into someones care plan but if each individual dietitian follows or advises (generally) on different plans, it just shows that the system does not create uniformity in guidelines or sound evidence to go off of. Nothing against dietitians, its a systemic problem. 

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On 7/23/2017 at 11:41 AM, NutritionRunner said:

NO one really knows about nutrition?  Really?  Hello, registered dietitians are the experts in evidence-based nutrition.  If, as a doctor, you aren't referring your patients who need dietary advice to a registered dietitian, you aren't doing a very good job.

BTW, most registered dietitians think that Canada's Food Guide is useless, which is why we advise clients to follow the Healthy Plate, the Mediterranean Diet, or the DASH diet.  However, truly getting clients to be able to make dietary changes requires TIME, something most doctors don't have.  So refer to the RD, who has 30-60 minutes per visit with a patient.

RDs are the nutrition experts.  If you aren't making use of them and are trying to advise your patients yourself on nutrition, you are doing your patients a huge disservice.

Outside of the hospital setting though, my understanding is that RDs aren't really covered (or sparsley under employer health plans), so I don't think its fair to say  "  If, as a doctor, you aren't referring your patients who need dietary advice to a registered dietitian, you aren't doing a very good job."

I agree RDs are well versed on the topic and have the time - but theres no need to dump on doctors for working in a hampered system. 

As for the time quote, well, FM doctors could have more time like allied health like naturopaths or chiro etc, if they were able to charge more for a visit. I would gladly spend 30-60 mins with patients if I could bill as much as Naturopaths bill for that time period.  But thats not the system we work with.

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12 hours ago, JohnGrisham said:

Outside of the hospital setting though, my understanding is that RDs aren't really covered (or sparsley under employer health plans), so I don't think its fair to say  "  If, as a doctor, you aren't referring your patients who need dietary advice to a registered dietitian, you aren't doing a very good job."

I agree RDs are well versed on the topic and have the time - but theres no need to dump on doctors for working in a hampered system. 

As for the time quote, well, FM doctors could have more time like allied health like naturopaths or chiro etc, if they were able to charge more for a visit. I would gladly spend 30-60 mins with patients if I could bill as much as Naturopaths bill for that time period.  But thats not the system we work with.

Here in Ontario, registered dietitians work as part of Family Health Teams and Community Health Centres.  So family physicians working in those settings can refer patients to registered dietitians and our services are fully covered by OHIP.  So if family doctors working in those settings aren't referring patients to dietitians, then they aren't doing a very good job!  In addition, many Community Health Centres make their dietitians available to other primary care physicians' patients who don't otherwise have access to a registered dietitian or who can't afford to access one (i.e. They don't have coverage for RD services).  At the two Community Health Centres where I've worked, I've always been able to see any infant, child, or pre-natal client who needed dietitian services, even if they weren't clients of our health centre.  Any family physician or pediatrician in the city could refer their patients to the dietitian under those circumstances.  At my current CHC, as a dietitian, I'm allowed to see any patient who can't access RD services in any other way, either because their family physician isn't part of a CHC or FHT, or they don't have extended health care benefits that cover RD services.  Patients aren't charged at all to see me, as my salary is paid by the LHIN.  Since I'm salaried, it doesn't cost the government any more if I see patients who aren't clients of our CHC.

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24 minutes ago, JohnGrisham said:

That is fair but definitely not the standard across Canada. That is a minority from my understanding, that is all I was getting it. Its great though you can provide those services in your locale!

It's trending in that direction though, especially in Ontario. Of the Allied Health services I want patients to access on a regular basis, RDs seem tl be by far the easiest to access and have covered by OHIP. I'll of course give my own basic dietary advice in most settings, but if there's any cause to go deeper, I'm pretty quick to suggest seeing the RD because they're relatively easy to see.

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On 2017-07-23 at 3:15 PM, rip said:

Sorry, I didn't mean it that way. I meant that nutrition evidence itself has shifted in so many directions that there is always research for and against everything else. Dietitians are the obvious experts in the field, but I'm worried that the evidence is not as clear as other fields where individual physiology, compliance to the diet, comorbidities and personal preference don't allow for clear conclusive evidence towards one dietary plan vs another. 

I'm very glad that RDs aren't going purely off the food guide. My experiences with RDs have been that they say they are taught to champion the food guide so that made me iffy. Much more knowledgable than any other professional in nutrition and dietary science but the system itself does not support their work by providing a terrible food guide or pushing society towards unhealthy behaviors/options.

Again, considering how vastly unique everyone's approach to nutrition is, there have also been differences between dietitians on the correct way to manage patients. Some may be strong advocates for whole foods plant based or LCHF or Mediterranean or DASH. They know when to implement each into someones care plan but if each individual dietitian follows or advises (generally) on different plans, it just shows that the system does not create uniformity in guidelines or sound evidence to go off of. Nothing against dietitians, its a systemic problem. 

Again, dietitians don't use Canada's Food Guide - why would we?  It's the government-produced document, and not an evidence-based one at that.  I've read the articles detailing how the last iteration of Canada's Food Guide was developed, and it definitely did not incorporate the best evidence on nutrition that we have available.  "Old school" dietitians may still use the Food Guide (i.e. I've heard of dietitians who finished their education back in the 80s using it) but most of us hate the Food Guide as much as many people do, and are excited for the upcoming changes to the Food Guide (and have submitted our feedback to the Federal Government on the changes we want to see).

Any dietitian worth their education is going to deliver tailored nutrition advice to an individual client based on their diagnoses, their lifestyle, their social characteristics, etc.  Their food security status.  Their culture and religion.  Their socioeconomic status.  Their family dynamics.  Their comorbidities (especially mental health).   Any barriers to making lifestyle changes.  Any supports.  Are they working, in school, on Ontario Works or ODSP?  Are they homeless?  Do they live in social housing?  Do they have a fridge?  A stove?  A hot plate?  A microwave?  All of these things are SO important.

 Depending on the individual, for someone with type 2 diabetes, we would start with "Just the Basics" from Diabetes Canada, and then move on to "Beyond the Basics" if the individual had the ability, skill, and desire to try carb counting.

We also look at how individuals respond to goals that we've set together, and then set new goals (and provide additional education) depending on their response to the goals we had previously set and how they were able to achieve them.  For example, if I provided someone with T2DM a meal plan based on a particular number of CHO servings, and their A1C improved, then that was probably a good # of CHO servings for them.  If their A1C didn't improve, then maybe there was something else causing the increase in blood glucose levels (which are affected by many things, including stress), or maybe we need to reduce the number of CHO servings.  If they felt tired all the time and had no energy, maybe their CHO servings need to be increased?

Of course, for some of my clients, given that I work at a Community Health Centre, sometimes something as small as adding one fruit or vegetable serving to their diet every day can make a big difference.  It doesn't always have to be a complete diet revamp, or following a particular eating style (whether that's Mediterranean, DASH, Beyond the Basics, or whatever else).  Many of my patients wouldn't be able to even begin to try to follow such a diet.  But if they cut back on their regular pop consumption, or switch to coffee with 1 milk instead of 3 cream 3 sugar, that can make a big difference to their health!

We examined LCHF diets and the research behind them in my master's program (which I just graduated from last year).  We don't have high quality evidence for their efficacy in human beings yet.  So until we do, myself, and other dietitians who are committed to evidence-based practice, will advise clients based on the best evidence out there, which many of us access through resources like Practice-Based Evidence in Nutrition, whose resources are always being updated based on the latest high quality evidence.

And of course there are differences between dietitians in their recommendations to patients - not all dietitians have identifical patients, and our advice is tailored to the individual, as I previously said.  I'm not going to give all my clients the same advice, so of course there are going to be different plans.  I won't advise a 20 year woman who is pregnant and who practices veganism to increase her iron intake by consuming animal products, I will talk about plant-based sources of iron, and ways to increase their iron absorption.  For a 70 year old woman with iron deficiency anemia and poor appetite, who is an omnivore, however, I will talk about meat, poultry, etc., as those will provide her with more concentrated source of iron, something important with low appetite.  I won't give someone with type 2 diabetes the same advice that I give to someone with Crohn's disease.  I won't give someone with hyperlipidemia the same advice as someone with end-stage renal disease who is approaching the need for dialysis.  I certainly don't give parents with a child who has failure to thrive the same advice as parents with a child who is considered overweight.

There is no one diet out there perfect for everyone, that is very true. And any dietitian worth his or her credentials and education will know that, and will tailor dietary advice to each individual, based on the best evidence currently available.

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3 hours ago, thestar10 said:

Eat food, not too much, mostly plants.

hehe.

For the average patient, they really just need to learn about portion control and cutting out junk food. That is a major part of the battle. All the nitty gritty isn't really all that necessary for the average patient but more so perhaps the more comorbid or complex patients, hence RD referral. But that doesn't mean there aren't some self-taught Drs that can handle it too in the outpatient setting.

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  • 4 years later...

I adhere to the principle that nothing can be done without the intervention of a doctor. An important element was the development of protein-preserving therapies for obesity, with an emphasis on the pioneering principle of George Blackburn. He recognized that protein-energy deficiency is a common and serious clinical pathology and developed new treatment approaches in hospitalized sedentary patients. Fat-free body weight can be maintained even during the use of very restrictive low-calorie diets used for weight loss. I came to my doctor with these thoughts and he selected diet plans simple and easy. So I'm not going back to my old weight. 

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