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EventsSugar vs fat on BBC: which is worse?
Sugar or fat, which is worse? That’s the question in the BBC documentary “Sugar vs. Fat” that aired the other night. And it’s been a long time since I got so many e-mails asking me for comments!
It’s an interesting setup. Two identical twin brothers – both of them doctors – go on a diet for a month. One on an extreme low fat diet, one on an extreme low carb diet (not even vegetables are allowed!). Here’s some background information:
MailOnline: One twin gave up sugar, the other gave up fat. Their experiment could change YOUR life
You can watch the show online here.
Unfortunately they end up mostly “confirming” their preconceived ideas. Ready? Here comes the spoilers:
Result
Obviously when there is only one person on each diet, chance plays a big role. But I think the findings were more or less what could be expected, it’s mostly the ignorant (or TV-drama) explanations I have objections to.
Weight
First thing first. Even though both brothers were at a fairly decent weight to start with, the low-carb brother lost the most weight: 4 kg (9 pounds) vs only 1 kg (2 pounds) for the low-fat brother.
As study after study show more effective weight loss on a low-carb diet, this should be no surprise. The loss of fat was 1,5 kg on low-carb (a good result in a month) and 0,5 kg on low-fat. Most of the rest was probably fluid. On a very strict low-carb diet you quickly lose a kilo or two of glycogen and water weight.
How much – if any – muscle mass the participants lost is impossible to know as the BodPod test only measures fat mass vs. non-fat mass (including water).
Brain function
For testing the brain function of the brothers the producers chose to make them do stock trading with fake money.
This shows that the producer is ignorant or just interested in a dramatic show. Why? Because short-term stock trading – without insider info or other illegal tricks – is a game of pure chance. It’s been convincingly shown that a trained monkey has a 50% chance of beating a well-educated stock broker. Why? Because it’s all chance.
In other words this test is rubbish, but the low-fat brother wins.
More interesting and relevant is that the low-carb brother complains of feeling “thick-headed”. I’m sure he’s honest. Going on an extreme low-carb diet – without even vegetables – can absolutely result in problems concentrating etc. for a week or even more, before the body and brain adapts to burning fat and ketones.
This problem can often be partially avoided by increasing the intake of fluid and salt. And after a week or two it’s normally gone.
Exercise
For testing their exercise capacity the brothers do “long sessions of uphill cycling”. The low-carb brother predictably loses badly.
Why? Two things: the body needs weeks or sometimes even months to adapt to high-intensity exercise, using mostly fat and ketones. And even then you might need a little bit of carbs for explosive and anaerobic sports like this.
I’ve interviewed Dr Peter Attia who successfully races his bicycle for hours on a very low-carb diet. Even he uses a little bit of slow-release starch for maximum performance on his long training sessions:
YouTube: Very Low Carb Performance
Diabetes
Finally the icing on the (diabetes) cake. The doctor claims that the low-carb brother has become “almost” pre-diabetic by eating low-carb! The word “almost” should actually be interpreted as “not”. I wonder if the doctor knows the first thing about low-carb and diabetes. In fact I wonder how much he knows about diabetes at all.
The low-carb brother has a fasting glucose of 5,1 before the diet (normal) and a fasting glucose of 5,9 after the diet (normal). Did you catch the word “normal” twice? Yes, thats right, a fasting glucose of up to 6,0 mmol/L is considered normal, at least in Sweden. It also varies significantly from day to day. If we tested the doctors’s own fasting blood glucose it might be 5,9 today and 5,1 tomorrow.
The result could be due to chance but sometimes the fasting glucose level actually gets slightly higher on an LCHF diet, while the glucose levels during the day (after meals) is way lower. This is probably because the body is adapted to burning fat and so the need for burning glucose when fasting is lower. Thus you don’t get the same fasting “dip” in sugar levels.
They also did glucose tolerance tests – a much more relevant test. But the result of the low-carb brother is never mentioned. I guess it was normal.
The fact that diabetes is effectively treated with a low-carb diet should tell us everything we need to know. You don’t get type 2 diabetes by eating a diet that can cure diabetes. And you certainly don’t get type 2 diabetes (strongly correlated to obesity) by losing 4 kilos of excess weight in a month.
Summary
The documentary concludes that it’s not about fat or sugar, it’s about avoiding processed food with both fat and sugar in it. I’m sure that strategy would work fine for these two fairly fit brothers. It’s an excellent start. But it’s not enough for everybody.
In people with obesity and diabetes studies convincingly show that low-carb diets are more effective.
Finally, while a super-strict low-carb diet is not necessary for everyone and has possible side-effects (especially during the first week or two) it certainly do not result in diabetes. That’s just ignorant.
What did you think about the documentary?
More
Diabetes – How to Normalize Your Blood Sugar
New Study: A Low-Carb Diet and Intermittent Fasting Beneficial for Diabetics!
Football Champions on a Low-Carb Diet
Swedish Expert Committee: A Low-Carb Diet Most Effective for Weight Loss
143 comments
ive been zero carb (bread, pasta, rice , white potatoes and cereal) for over 5 years (tonnes of veg) and at 40 I have never felt better.
I play professional paintball with games lasting 7-8 hours without break and do just fine.
I powerlift as well and since dropping carbs ive got stronger, leaner and faster.
Ive recomended the paleo way of eating to many friends and clients who have type 2 and all have had fantastic results whih seem to confuse the so called experts. (No surprise)
Why are they still clinging to the dogma its Ancel Keyes all over again!
These people need to face facts and embrace a soloution that doesnt require the sale of medications.
After reading taubes books and researching the subject myself with the help of your great website its obvious to see the many benefits and studies supporting this way of eating.
I plan to start my new journey on monday, I am a healthy weight 29 year old male who works out with heavy weights 3 times a week...i am not doing this to lose weight or control diabetes but just that i believe that our bodies are not adapted to be eating all the processed rubbish and sugar and the feelings and problems that come from it....plus i love my coconut oil coffees in the morning :) Great website and really great source of information for the new comer, i shall be recommending
They had their cholesterol tested before and after but the exact results were never mentioned, just that they were normal before and after. Why didn't they give the exact ldl hdl levels?
Nothing was mentioned on actual calorie intake.
As for the low card high fat diet, it appeared extreme as there was no mention of eating vegetables , so unrealistic diet.
Interestingly enough they didnt dwell on the point that on the high fat diet cholesterol didn't increase, they seemed to skip over it.
The end conclusion was sensible about the sugar and fat processed foods causing people to gorge on that type of food , so suggested to avoid it, but no mention on how to avoid it. They could have mentioned, as shown in the experiment that when you eat a fat/protien low carb meal you don't each as much and controls appetite better.
I do agree that this programme has told us nothing new, however; it has confirmed peoples fears in the UK that low carb is not healthy. I call that irresponsible.
So the low carb guy lost 1.5kg of fat and 2kg of FFM, the high carb guy 0.5 kg of each. They didn't start from the same body composition or weight.
Du är svensk och har en svensk blogg, Varför inte bara skriva det hela på svenska med.
Tack.
I suspect he ate a ton of protein.
They should have had a 2 week washout and reversed diets in a crossover protocol, as well as getting advice from low carb experts rather than the carb queen they employed - see her breakfast suggestions at http://www.amandaursell.com/?page_id=988 ( LOL )
The twin docs have done better in the past http://www.channel4.com/programmes/medicine-men-go-wild/4od#2923146
The experiment had various flaws, one being that they were purely studying Fat/Sugar, although protein was mentioned, it wasn't given an equal value (implying that the protein consumed in the test was classified as fat ??).
The stock market test was practically irrelevant, as we didn't know their experience, interest or natural aptitude prior ?? The same for the bike test, although the blood test during was informative!
The 'Fat' they chose included dairy, which obviously is greatly sugar in the form of 'lactose'?? Plus an amount of processed meats including; burgers & sausages that probably had an amount of ingredients we don't know about ??
It would've been better if they showed the high effect of healthy carbs in the form of fruit & veg, plus 'healthy unprocessed' protein as one diet, against a diet of processed meats, and simple processed carbs, they would've had a different & probably more beneficial result.
In addition, the mention of muscle loss wasn't qualified by giving the viewer the information that; if you exercise the muscle while reducing calories, more muscle is retained & a greater portion of fat lost. The fact that they only cardio exercise as an example, although not explained, only went to prove what educated health professionals should know, a combination of muscle based exercise keeps/increases your metabolism, cardiovascular exercise on a calorie reduced diet will only eat that muscle and thereby reduce metabolism.
Yes we know that 'during an event' athletes require/benefit in performance, with using simple carbs as immediate energy, but most of us are not 'athletes in competition. I thought the study was for weight loss not performance ??
The only useful part was in the summary, where they deduced, to avoid processed foods, as they contain the 50/50 combination of fat/Sugar that is directly related to gaining weight and making us unhealthy.
I'm more than happy to discuss this further or help anyone wanting to improve their health, fitness and physique !
http://fitforyou.co.uk
I was completely disappointed with this program making me wonder if the sugar industry were not promoting it.
The good thing is it encourages discussion.
I will continue on my LCHF journey...watch this space.
After the brief inteview with Robert Lustig, the effect of insulin on storage of fat was described as the "Insulin Hypothesis", yet the idea that saturated fat and cholesterol block arteries, and are bad for you, was given the status of fact set in stone, and not accorded the more accurate description "Lipid Hypothesis".
Weight:
One point you do not mention is the loss of muscle mass: the low-carb twin's lost 2kg of muscle mass against 0.5kg loss of muscle mass on the high-carb twin. I do not know enough to comment on the loss of muscle mass, or whether the method of measuring is accurate or appropriate.
The twins repeatedly put the loss of weight down to calorie consumption-the low-carb twin eating less calories due to satiety eating fat.
Brain Function:
I also thought that it was a poor test. Even if the results were not down to chance movements in the stocks being traded, it could simply be that one twin is more comfortable with that particular situation and performs better as a result.
Exercise:
I agree with your comments on the exercise test. For a quick explosive burst of energy, some carbs may be useful.
Diabetes:
The twins commented on their insulin levels post-test, the low-carb twin having a slightly fasting glucose than pre-test and a lower insulin level. He described this as insulin resistance. Forgive me if I am wrong, but isn't insulin resistance high-insulin coupled with high blood sugar, not the low insulin that he exhibited.
The high-carb twin did have high insulin, "your body's ability to produce insulin improved". I thought of this as "Eating sugar is good for you as your body gets better at producing insulin". It was admitted that, long-term, this could be problematic, but possible development of insulin resistance and diabetes was not explicitly mentioned.
In fact, to me, the subtle inference seemed to be that the low-carb twin was at a greater risk of developing diabetes than the hig-carb twin, should they continue with thier diets.
All in all, as you say, the twins had their pre-conceived ideas confirmed. They did admit that some of the results surprised them, as they went against what they had been taught at medical school.
Surely the summary of the article gives us an important point. So called "supermarket, trash" diet consisting of 50/50 sugar/fat is the worst thing you can do for your body. Picking either of sides already does well for organism.
A question to those who workout on low-carb diet, do you eat some carbs before an intensive workout session? Or just a meal containing fat 1,5-2h before?
Glucose tolerance has to be interpreted carefully on LCHF. If you abstain from alcohol for a while, your alcohol shock response will be less tolerant. Abstaining for a while and giving the system an unnatural shock catches the metabolism unprepared for a binge. Just like alcohol. Don't binge. Sugar is the new alcohol. If the LCHF twin did not have a poorer sugar binge tolerance test, it suggests the adaptation period was not long enough for him or that he failed to engage the epigenes for keto-adapted phenotype for some reason.
I expect the sudden, drastic shift from excess carbs to zero carbs was too great a shift for the LCHF twin's metabolism to adjust epigenetically in that short a time. I expect his thyroid activity dropped off, explaining the low energy and coldness. Dr. Cate Shanahan counsels gradual reduction of carbs and does not have the thyroid symptoms many people get going very low carb cold turkey.
Anyway, discovery was not the purpose of the media stunt. It was driven by confirmation bias. Otherwise they would have consulted well known expects in such experimental design like Drs. Phinney or Volek.
http://jap.physiology.org/content/110/1/236.full.pdf
For longer endurance at very high intensity, slow carbs are useful. Nuts seem to be popular for that. I generally measure fasting glucose in the morning. 4.7 or more indicates to me I am glycogen replete. Below 4.7 and I figure I have some room to take in carbs without elevating blood sugar above 5.0.
No need for forgiveness. :)
Murray, is the book you recommend available in the online version? Havent found it.
In order for a glucose tolerance test to give accurate results the patient is not allowed to restrict carb intake for days/weeks before the test. Something the fat-twin obviously didn't do. If you do a GT test when in ketosis all the glucose will be spared for your liver, the muscle won't grab any. So in this sense, they are insulin resistant. But this is NOT a sign of pre-diabetes, just that your muscles use ketone bodies instead of glucose when they're available.
There is of course a fundamental issue with both the lack and quality of true research into low carb high fat eating. There are no genuinely tier one studies into this way of eating. I am personally an advocate of LCHF as it works for me , unfortunately the scientific evidence base for the validity of LCHF is thin on the ground.The psuedo science posted in more than a few responses here would give Ben Goldacre apoplexy
But what can you expect from a sensationalist program such as Horizon has now become?
Like almost everyone else here I am proof that LCHF is healthy, safe and works, and in the long as well as short term too.
http://www.jbc.org/content/83/3/747.full.pdf
Part of this has resulted in an extreme aversion - I could almost call it an allergy - to scientific facts and especially mathematics. The BBC seems to be entirely staffed by people with Arts degrees who understand nothing about science, and think of it as a black art. (I have an Arts degree too, but I have taken the trouble to learn a little about math and science). Except, ironically, for economics and finance - on which topics vast amounts of incomprehensible numbers and jargon are routinely emitted.
I could have predicted the outcome of any program about diet on the BBC. Namely, complete endorsement of the established lipid hypothesis (except that they don't think of it as a hypothesis, but Holy Writ).
It seems the only conclusion that was drawn was related to something that wasn't even part of the original test (apart from some strange doughnut-choosing survey). Apparently rats get fat eating cheesecake. Who knew?
Poor show, BBC, poor show.
No! You don’t need the BMI to see that. They had their shirts off! Both these gents were clearly fat.
Totally surreal. Straight out of 1984. We have designed a system that can honestly tell us that two seriously unhealthy looking men are not overweight. What a load of BS.
But then again, it works well if the target is to normalise obesity in a country where people carry lots of body fat but very little muscle.
Britain is the third fattest country on the planet, but with the BBC at the helm, we’re gunning for that number 2 slot!
If you want to see what a 181 lb weight loss looks like - http://www.atkinsdietbulletinboard.com/gallery/showimage.php?i=5333&#...
Participant : "Am I overweight?"
Doctor "well, we have to look at your BMI first"
... dooo!
The BMI is about the worst approximation of overweight.
He already has an exact bodyfat measurement and still trusts the BMI more.
Here a chart that shows, that having a bodyfat% of 25 can mean a BMI of as low as 19 (skinnyfat),
up to 40 (bodybuilder)
http://upload.wikimedia.org/wikipedia/commons/b/b7/Correlation_betwee...
HAH!
Useless.
Last year at this time, we happened to watch the “Healthiest Heart” episode in the “Medicine Men Go Wild” series. In this series, these same twin physicians studied medical and dietary practices in remote cultures.
In the HH episode, the subject was the Inupiaq Eskimos, who subsist on walrus, whale and fish. The doctors were pretty much bewildered by how healthy most of these people were (and their lack of disease) given this must-be-horrible high-fat, moderate protein, almost-no-carb diet. Being apparently unaware of NK (nutritional ketosis), they managed to credit it to high levels of exercise. The one guy in the village with bad labs, no surprise to followers of this blog, was found to be eating wheat products from the outside world.
As for the BBC, the least said about that organisation, the better.
http://www.amazon.com/The-Art-Science-Carbohydrate-Performance-ebook/...
I don't know much about weights and diet. Jeff Volek and Dominic D'Agostino (university south Florida researcher into using ketogenic diet to treat cancer and military use of ketogenic diet) are both into lifting and ketogenic diet. I recommend seeing what they have written.
Poorly done. These guys clearly want to be popular and have their face on TV. They have ignored or disregarded REAL doctors like Dr. Lustig - who has done ALL of his own research, not just stomping on the work of others for the sake of air time.
Please search on youtube Dr Jason Fung: he is a Canadian kidney specialist who got tired of patients destroying their kidneys with diabetes. he has an intensive treatment for diabetes (a combination of LCHF and of skipping breakfast) - LCHF and partial fasting - which CURES type 2 diabetes.
The idiots who did the ridiculous comparison know nothing of physiology. Type 2 diabetes is CAUSED by insulin resistance, itself caused by high insulin levels (resistance, or tolerance, is the way the body reacts to an abnormally high level of any substance). The same goes with alcohol: alcohol resistance is CAUSED by alcohol. To suggest that a high carb diet is good for diabetes and a low carb one dangerous is totally ridiculous.
Dr FUNG gives a series of examples of patients who started taking high doses of insulin or multiple drugs. Nearly all now are drug free with normal glucose levels (a few of the most severe patients still take some medication, but much less than what they were previously taking).
Please see Yoshifumi Y, Uchida J et al., A non-calorie-restricted Low-carbohydrate Diet
is Effective as an alternative therapy for patients with Type 2 Diabetes.
Intern Med 53: 13-19, 2014
They have clearly demonstrated that even a partial restriction of carbs gets the HbA1C and the triglycerides down while a calorie-restricted but any carbs allowed diet changes nothing.. When carbs are 75g-135g per day, the effect is temporary and after 4 months, HbA1C starts creeping up slowly on average. A more severe restriction of carbs is necessary (50g or less) WITH partial fasting (skipping breakfast) to bring insulin levels down and growth hormone levels up and normalize blood glucose.
See Kral TV, Whiteford LM, Heo M, Faith MS. Effects of eating breakfast compared with skipping breakfast on ratings of appetite and intake at subsequent meals in 8- to 10-y-old children. Am J Clin Nutr. 2011 Feb;93(2):284-91. doi: 10.3945/ajcn.110.000505. Epub 2010 Nov 17. for an interesting analysis of what really happens to patients who skip breakfast.
Good luck with your diabetes control: you seem to be well on your way to normalizing your glucose and you definitely are doing the right thing.
http://www.drbriffa.com/2014/01/30/my-take-on-the-horizon-documentary...
How deep will we be willing to digg ?
https://ssl.bbc.co.uk/faqs/forms/?eid=&id=RRCNUJJN2R8QBNQCKB50I5...