Today's Funny Friday video is an amazing PSA in support of organ donation.
Are you a donor? If not, maybe that could be your project for the day?
Have a great weekend!
Friday, August 26, 2016
Thursday, August 25, 2016
Weight loss diet studies: we need help not hype
Over the past several decades, dozens of randomised controlled trials have compared various diets for the treatment of obesity. Ideally, such studies should have provided strong evidence for clear clinical recommendations and also put a stop to society’s endless parade of fad diets. Unfortunately, the evidence base remains contested and the “diet wars” continue unabated.
One insight that can be gleaned from the existing weight loss literature is that even the most divergent of diets seem capable of affecting a degree of short-term success, with some diets perhaps leading to marginally greater losses than others over periods of several months.1 But since obesity is a chronic condition, it is the long term that matters. An effective diet for clinical weight management needs to be established over time scales of years to decades. Studies that have lasted 1 year or more typically do not show significant differences between prescribed diets, much less any clinically meaningful differences in maintenance of lost weight.1, 2 One example is in the Dietary Intervention Randomized Controlled Trial (DIRECT), which has been hailed as proof of the superiority of low-carbohydrate diets over low-fat diets.3,4 The DIRECT investigators used a 2-year workplace intervention and found that a low-carbohydrate diet prescription led to a significant 1·8 kg greater mean bodyweight loss than the prescription of a low-fat diet.3,4 These bodyweight differences between the diets are among the largest differences that have been observed over a 2-year period. But from the clinical perspective, such small bodyweight differences do not instil confidence for prescribing one diet over another to a patient with obesity.
What is especially striking is the similarity of the long-term pattern of mean bodyweight change, irrespective of diet prescription.5 For example, figure 1A shows data from the DIRECT study in which both the low-fat and low-carbohydrate diets resulted in rapid early weight loss that plateaued after about 6 months at a likely disappointing level6 and was then followed by slow bodyweight regain. What can we learn from the physiology underlying such a bodyweight trajectory?
Complex physiological feedback mechanisms regulate bodyweight and resist weight loss. Slowing of metabolism can be substantial and persistent7 and plays a part in halting weight loss and putting subsequent weight regain into motion. However, the typical bodyweight trajectory is primarily driven by patients experiencing an exponential decay of diet adherence due to an increase in appetite in proportion to the loss of bodyweight,8 along with difficulties in sustaining changes to dietary choices and behaviours that affect patients’ ability to enjoy, celebrate, and socialise with food.
Figure 1B shows the energy intake changes underlying the DIRECT trial’s observed bodyweight trajectories, which we have calculated using a validated mathematical model of human energy metabolism and bodyweight dynamics.9 At the plateau point of maximum weight loss, energy intake is balanced by expenditure and has decreased from baseline by about 200 kcal per day. By contrast, mean energy intake at the bodyweight plateau has increased by about 700–1000 kcal per day from its early reduction at the start of the intervention. After 1 year, mean bodyweights, although still reduced by several kilograms, climb back up in response to the average energy intakes returning almost to baseline levels.
Diet adherence is so challenging that it is poor even in short-term studies where all food is provided.10 When diets are prescribed, adherence is likely to diminish over the long-term despite self-reports to the contrary. Figure 1B illustrates that the common self-report methods for measuring food intake (24 h recall and food frequency questionnaire3,4) mistakenly indicate that the reduction in energy intake remained unchanged throughout the intervention. Such erroneous measurements have led to speculation that a reduction in energy expenditure, rather than loss of diet adherence, is the main driver of the bodyweight plateau. However, these self-reported measurements are known to be inaccurate for estimating energy intake11 and provide unreliable data on energy intake changes that are not quantitatively reconcilable with objectively measured weight regain and the known physiology of energy metabolism adaptations.
Nevertheless, and hearteningly, anecdotal long-term diet success stories abound for most dietary approaches, and focusing on mean bodyweight trajectories masks the high individual weight loss variability within each diet group. The question is: why are some individuals more successful than others? When it comes to clinical weight management, success is predicated on long-term dietary adherence. Therefore, we need to increase our efforts to understand the individual differences between patients that have an effect on diet maintenance and prevent its erosion. Studies should determine how to target effective diets to individual patients,12 as well as improve our understanding of the real world considerations that impinge on patients’ abilities to sustain healthy dietary changes,13 such as those wrought by the food environment, socioeconomic factors, cooking skills, job requirements, medical comorbidities, caregiving responsibilities, and many more. After all, as with every chronic disease, successful obesity management requires lifelong treatment and there is a pressing need to help patients navigate day-to-day realities in the face of maintaining a permanent and intentional behaviour change. We also need to better understand how family, community, and society as a whole can help support and sustain healthy lifestyles.
Fewer resources should be invested in studying whether or not a low-carbohydrate diet is marginally better than a low-fat diet, or whether intermittent fasting provides marginally better short-term outcomes than a so-called Paleo diet. Crowning a diet king because it delivers a clinically meaningless difference in bodyweight fuels diet hype, not diet help. It’s high time we started helping.
Yoni Freedhoff, *Kevin D Hall
YF has received honoraria and travel expenses from Boston Children’s Hospital, Canadian Obesity Network, Centre for Effect Practice, Academy of Medicine Ottawa, Physical and Health Education Canada, North York General Hospital, , IDEA Health and Fitness Association, and the Royal Society of Medicine, London, for speaking engagements and for his role as clinical lead in the development of a Canadian Ministry of Health funded tool for primary care providers working with families of children with obesity; and has received fees for developing and delivering educational seminars to medical students and residents from the University of Ottawa. YF writes a blog, Weighty Matters, that is non-monetised with no advertisements or requests for donations. YF is the co-author of Best Weight: A Practical Guide to Office-Based Obesity Management all royalties from the book go to the Canadian Obesity Network and he is the author of The Diet Fix (Random House) and receives royalties from this book. KDH reports a patent pending on a method of personalised dynamic feedback control of bodyweight (US Patent Application No. 13/754,058; assigned to the National Institutes of Health) and has received funding from the Nutrition Science Initiative to investigate the effects of ketogenic diets on human energy expenditure.
1 Johnston BC, Kanters S, Bandayrel K, et al. Comparison of weight loss among named diet programs in overweight and obese adults: a meta analysis. JAMA 2014; 312: 923–33.
2 Tobias DK, Chen M, Manson JE, Ludwig DS, Willett W, Hu FB. Effect of low-fat vs. other diet interventions on long-term weight change in adults: a systematic review and meta-analysis. Lancet Diabetes Endocrinol 2015; 3: 968–79
3 Greenberg I, Stampfer MJ, Schwarzfuchs D, Shai I. Adherence and success in long-term weight loss diets: the dietary intervention randomized controlled trial (DIRECT). J Am Coll Nutr 2009; 28: 159–68.
4 Shai I, Schwarzfuchs D, Henkin Y, et al. Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. N Engl J Med 2008; 359: 229–41.
5 Franz MJ, VanWormer JJ, Crain AL, et al. Weight-loss outcomes: a systematic review and meta-analysis of weight-loss clinical trials with a minimum 1-year follow-up. J Am Diet Assoc 2007; 107: 1755–67.
6 Foster GD, Wadden TA, Vogt RA, Brewer G. What is a reasonable weight loss? Patients’ expectations and evaluations of obesity treatment outcomes. J Consult Clin Psychol 1997; 65: 79–85.
7 Fothergill E, Guo J, Howard L, et al. Persistent metabolic adaptation 6 years after “The Biggest Loser” competition. Obesity (Silver Spring) 2016; published online May 2. DOI:10.1002/oby.21538.
8 Polidori D, Sanghvi A, Seeley RJ, Hall KD. How strongly does appetite counter weight loss? Quantification of the feedback control of human energy intake. Obesity (Silver Spring) 2016 (in press).
9 Sanghvi A, Redman LA, Martin CK, Ravussin E, Hall KD. Validation of an inexpensive and accurate mathematical method to measure long-term changes in free-living energy intake. Am J Clin Nutr 2015; 102: 353–58.
10 Das SK, Gilhooly CH, Golden JK, et al. Long-term effects of 2 energy-restricted diets differing in glycemic load on dietary adherence, body composition, and metabolism in CALERIE: a 1-y randomized controlled trial. Am J Clin Nutr 2007; 85: 1023–30.
11 Dhurandhar NV, Schoeller DA, Brown AW, et al. Energy balance measurement: when something is not better than nothing. Int J Obes (Lond) 2015; 39: 1109–13.
12 Bray MS, Loos RJ, McCaffery JM, et al. NIH working group report-using genomic information to guide weight management: from universal to precision treatment. Obesity (Silver Spring) 2016; 24: 14–22.
13 MacLean PS, Wing RR, Davidson T, et al. NIH working group report: innovative research to improve maintenance of weight loss. Obesity (Silver Spring) 2015; 23: 7–15
Tuesday, August 23, 2016
But I bet they'll be back.
It's great business for the food industry to state directly (like Coca-Cola's Global Energy Balance briefly tried to) or indirectly that exercise excuses (or balances) a crappy diet.
Though exercise is the world's best drug, as I've noted, it's not a weight loss drug, and though exercise absolutely mitigates the risks of both weight and likely diet too, that McDonald's believes fitness trackers to be a Happy Meal draw is worrisome.
It's worrisome because McDonald's belief that kids and their parents would see the activity trackers as both incentive and permission to eat there suggests that society is well and fully bought into the notion that exercise trumps diet.
So too does the much lauded scheme floated a few months ago that foods fronts-of-packages be festooned with "activity equivalent labeling".
|"HAVE YOUR CAKE AND EAT IT TOO! (We'll help you work it off!)"|
Saturday, August 20, 2016
David Satter in National Review on how terrorism brought Putin to power.
Maggie Koerth-Baker in FiveThirtyEight answers the age old question of how big a fart is.
Friday, August 19, 2016
If you didn't see this chat with two fantastic Irish rowers then yes, yes you did miss Rio's greatest interview.
Today's Funny Friday video is here to fix that for you.
Have a great weekend!
Thursday, August 18, 2016
In that time we have worked with literally thousands of patients and while they were each unique and had their own sets of medical concerns and life challenges, they did share one thing in common - they all lived in or near to Ottawa.
In the beginning, that was a necessity. The technology to work with patients remotely simply didn't exist.
I'm thrilled to report that it does now.
For the past few months we've been working with a smartphone app that lets us reach our patients even when they're not sitting in front of us. The app allows us to create customizable and trackable goals that we can monitor remotely (and reach out if we see someone's struggling), and more importantly, the app provides two-way communication - both by way of quick text messages, but also by way of video conferencing, between patients and our office's professionals. While so far we've pretty much only been using the app with our Ottawa based patients, we're about to open our virtual doors and in so doing, use the app to work with anybody, anywhere.
We've designed a 12 week program that will be delivered by our office's registered dietitians to help people with their weight loss and behavioural change goals (and once formally launched, there'll be ongoing support options available once completed). During those 12 weeks people will have regular videoconferences with our RDs and work with them on creating personal goals that are designed to target each individual's specific needs, concerns, and barriers. They will also have access to our RDs by way of the app supported (and both PHIPA and HIPAA compliant) text messaging for quick questions and words of support.
While we will soon offer access to this program to everyone, right now we're looking for 5 volunteers to work through our new program with us and help us iron out the kinks in its delivery. In return for our best efforts to help you achieve your Best Weight, we’re looking for individuals who are comfortable giving us honest feedback on what’s helpful in our program and just as importantly what’s not.
Because the supporting program curriculum is still being developed (videos and articles that will accompany the 12 weeks and serve as offline resources) there is the requirement that those interested own and read my book The Diet Fix: Why Diets Fail and How to Make Yours Work as it will serve in the offline course curriculum's stead. As well, for the beta-testers only, we need to restrict the offer to those with iPhones as we’re still working out some of the issues with the Android operating system.
If you're interested in being considered as a beta-tester, please send us a letter telling us a bit about you and your history with weight loss (please limit the letter to no more than 400 words), and in 2 weeks we'll contact those who our RDs select. We're looking for divergent people and issues and consequently can't simply take the first 5 people who write. That said, if you do write in and you're not selected, we'll be sure to put your name in the queue for when our program formally launches and make sure you’re at the top of the list.
Please send your emails to email@example.com.
We're so excited to be rolling this out!
Posted by Yoni Freedhoff at 5:30 am
Tuesday, August 16, 2016
|Image Source: ThinnerGene|
But does it?
That's the question a recently published randomized trial sought to answer. The study, The effect of the apolipoprotein E genotype on response to personalized dietary advice intervention: findings from the Food4Me randomized controlled trial, randomly assigned 1,466 participants to a 6 month trial of one of 4 interventions.
1. Standard non-personalized dietary and physical activity advice
2. Personalized advice based on dietary intake
3. Personalized advice based on dietary intake, physical activity, and standard blood biomarkers
4. Personalized advice based on dietary intake, physical activity, standard blood biomarkers, and genotyping
The genotyping was for apolipoprotein E (APOE) which in turn is thought to be a key regulator of cholesterol and lipids. It's also thought that differing APOE genotypes influence lipid responses to dietary fat and therefore given the known increased risk of certain APOE genotypes with coronary heart disease and on lipid responses to dietary fat, that risk carrying individuals if told about their genotypes, might be more likely to adopt gene-based personalized nutrition recommendations.
The study's findings aren't particularly heartening for personalized medicine as it pertains to individual behaviour change.
Personalized advice was found to be better than non-personalized advice, but there was no additional benefit to change found with those whose personalized advice warned them that their unique genetic makeups conferred greater risk.
There is a silver lining here though. Personalized advice based on an individual's dietary intake alone was just as likely to inspire change. So rather than spending your money on all sorts of tests, if you're worried about some diet related aspect of your health, go see an RD (but maybe not one who tries to sell you personalized genetic testing), and with the money you save on all that other testing, you can book a few follow ups and likely get an even bigger bang for your buck.
Saturday, August 13, 2016
David Schraub in The Tablet on how words and Black Lives both matter.
Richard Landes in Fathom on the left's Venn overlap between anti-zionism and anti-Semitism.
Friday, August 12, 2016
Wednesday, August 10, 2016
It's called Raise a Patch and it's an Australian initiative that I adore. It's fundraising (school, sports team, whatever) by way of selling "veggie patches", herb pots, and flower gardens.
Healthy foods, beautiful flowers, and the joy of gardening? What's not to love. Hope this catches on globally.
(and if you're looking for more healthy fundraising inspiration, here's a compiled list of other Aussie programs)