45 Responses to “Horizon: Sugar vs. Fat”

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  1. avatar Carol B says:

    What a breath of fresh air! I wrote a similar blog calling out the dumbed down and questionable “science” of Horizon these days. It was for Huff Post but their word count is so restrictive I let it go – there wasn’t space to do it justice.

    I am looking forward to your blog about the most recent travesty of Horizon’s What is the Best Diet, the 3 part series that aired this last week which was also full of dumbed down “science”, unanswered questions and imho wrong thinking at the most fundamental level of nutrition.
    Thanks for your work.

  2. avatar Juliet says:

    Thank you!
    I’ve just finished watching this documentary and I could not believe the conclusion that was reached. Thank you for calling out this misleading bullshit.

  3. avatar Zeny says:

    In the US mayo has no sugar typically. Is it a UK thing?

    • avatar Zoë says:

      Crikey Zeny – I can’t believe the US has missed out on a chance to add sugar! UK mayo tends to have added sugar…
      Best wishes – Zoe

      • avatar stuart says:

        There’s actually ‘good’ and ‘bad’ mayonnaise – Helmans or home made generally has negligable carbs/sugar, but lower cost mayo in us/uk is much higher. Its so easy to make yourself though, and then at least you know exactly whats in it.

  4. avatar Sophie says:

    This is a really great article Zoe, thanks.

    I’ve been increasingly interested in nutrition over the past year or so and have recently read Dr. Lustig’s fabulous book ‘Fat Chance’ and David Gillespie’s book ‘Sweet Poison’. My eyes have been opened to the perils of sugar and the healthy or ‘real’ way of eating. The problem I have found is that when I tell other people about what I’ve learned, they dismiss the realities of a high fructose diet. I’m now trying to tell more people about what I now know through my blog. I don’t have a science or medical background, so my approach is a fairly light touch! I’m glad I came across your blog, I’ll be back for more.

    Sugary Desire – http://www.body-in-bloom.co.uk/1/post/2014/02/sugary-desire.html
    What does the WHO recommendation on Sugar mean to your daily diet?

  5. avatar brian bissenden says:

    I am not sure why you think that Dr Mckenzie would be using a £10 Prodigy AutoCode Talking Blood Glucose Monitoring Meter Kit in his Laboratory at Westminster. As a scientist if he states that the readings is 5.1 then it is 5.1 unless you have any evidence to say otherwise .

  6. avatar carol says:

    I didn’t see the programme but I’m following your discussion with interest. As an ‘old school’ nurse ( I have worked mainly in cardiology) I have has never seen as many poorly controlled diabetics in my 41 year professional nursing experience as I do now. I (covertly!) followed the Atkins diet a few years ago. I lost about 3 stone. my lipids were unchanged and I felt great. I confess some pounds have crept back on as I slipped back into bad habits and I’m back on the low carb path. Good luck, Zoe.

  7. avatar Lisa Chase says:

    Hi Zoe-

    Thanks for this review; I was totally irked by this program, and it was nice to read some words of wisdom. One more point I wanted to bring up: if Xand went quickly from a high carb diet to a very low carb diet, and lost water weight (as you rightly mentioned)- he probably also lost a lot of sodium and potassium at the same time. Ketogenic diet experts (like Dr.s Phinney and Volek, or Dr. Westman at Duke University)- recommend that in the interim, extra sodium, magnesium and potassium should be consumed, until one becomes keto-adapted. (As you mentioned, he probably never was fully keto-adapted, as he continued to crave carbohydrates). Anyway, there was no mention as to whether Xand was taking these extra precautions (probably not, as there were no low-carb experts on the show). Apparently, this loss of important minerals can make one feel pretty bad for a time, and would have also explained why he did so poorly on the mental and physical tests he was given….(although in addition, as there were no “control” tests- i.e., how well did each brother perform before they went on their various diets? We have no way of knowing if one brother were more talented, or in better physical shape than the other). I think the word “science” should not be used in conjunction with this show at all, but it makes me irate that some people may watch it and believe they’ve learned something.

    The bias was obvious, right from the words “the low carb diet will give you bad breath and make you constipated”. I personally find a low fat diet causes bad constipation (never had any problem on low carb), and refined sugar causes the worst breath of all. In addition, all of the things that are normally positive about a low carb diet they gave a certain “spin” to, to make them appear negative. I didn’t understand what was so “bad” about the low carb twin not being able to eat a huge lunch only 3 hours after eating a huge breakfast! No wonder he wasn’t enjoying his food, he wasn’t hungry yet. And if they were trying to find the answer to the obesity epidemic, well, wasn’t that the answer right there? In addition, they claimed that fat messes with the hormone ghrelin. But had they actually listened to Dr. Lustig, he would have explained that excess fructose actually dulls our sense of satiety; i.e., it’s the other way around, and it’s the lack of satiety that’s abnormal. But alas, I guess only so much information can be divulged at a fairground…..

    Well, I could go on and on, but I won’t for now……

  8. avatar Chloe Archard says:

    Thanks so much for this Zoe. The program me drove me mad when I watched it as the experiment was so badly designed. This post is exactly what I wanted to say to my husband when I tried to explain all what was wrong with that program to him!

  9. avatar Ricki says:

    Good point, although arguably this is probably the only time this mix is provided to man and provides the most calorie dense food needed by the baby to sustain the phenomenal growth and development at the only time it is needed.

    Vital nutrients aside isn’t it the job of mothers milk to make the baby as ‘well fed’ or large as possible as quickly as possible to give it the best chance of survival? We tend to judge the health of a newborn by how quickly they put on weight, and I’m reminded of comments by the midwives when my son was born “he’s feeding well” “he’s gaining weight at a good rate” etc etc

    Maybe that is the problem today and if the mix of fat/carbs is indeed the problem then we have inadvertently created a nation of overweight and overfed adult babies consuming mothers milk equivalent waiting for a growth spurt that is sadly never coming!

  10. avatar Chris Wren says:

    Breast milk contains both fat and carbohydrate and is natural.

  11. avatar Naomi Rosenberg says:

    Thanks so much for your reply! I just read the Diet & Health Today article and it is a real eye-opener. Now I have another question.

    I’m confused about how available fat-calories really are to the body when it needs energy. From the article and your reply it seems that if we need energy and there are no carbs available at that moment, we will simply start burning fat (dietary or body) instead. But this seems at odds with what you say about Xand’s performance in the brain test. There, it looks like you are saying that Xand’s body could not access the fat-calories (even though he needed them in the short-term) because he was not in ketosis due to the presence of carbs in his diet.

    Is there a danger-area, a carb quantity range which does not provide enough in itself for energy, but somehow stops the body going into ketosis, blocking access to calories from fat? Leading to listlessness and poor mental performance?

    Thanks again, Naomi

  12. avatar Naomi Rosenberg says:

    Hi Zoe, I have just discovered your work and I find it fascinating.

    Please could you explain some more about how the body makes different use of sugar vs fat?

    In particular, a related point you make in another post – that carbs cannot be used for body maintenance, and are best placed for use in non-BMR energy expenditure through exercise. This articulated something for me – I’ve long suspected a major cause of obesity is that we are eating food our body can’t use for its vital processes and so we crave more and more.

    How much of the BMR is directly used in body maintenance? I’m guessing that some of the BMR is used to power the heart, and consumed in the brain, and other energy usages that can make use of carbs. I’m interested in how much of it HAS to be fuelled from non-carb sources.

    Could you point me to some facts and figures on this? Thanking you in advance – meanwhile I’ll keep reading!

    • avatar Zoë says:

      Hi Naomi – I raised this concept in an article here and in a video here.

      The BMR is strictly the resting metabolic rate – we say to people to think of it as the calories needed if you’re lying in bed all day too ill to move. Yes – an element of this still includes fuel for even the tiny amount of movement that does take place, but the vast majority of what the body needs to do if we’re not moving, is managing the 9 body systems: nervous system; skeletal system; endocrine system; reproductive system; digestive system; circulatory system; lymphatic system; urinary system and respiratory system. Hence I’m trying to get people to think about food intake needed for repair/maintenance (think of this as closest to BMR) and food intake needed for energy.

      Then the Harris Benedict work (dating back almost 100 years ago) is still very useful. (I don’t normally quote wiki, but this is a good summary of the Harris Benedict equations.)

      Then – any biochemistry book will tell you about food metabolism – carbs, fats and proteins. Some nutrition books may get it right but most get it wrong and say that you need carbs for energy. We don’t. The body can use dietary fat (or body fat) for energy. It will prefer carbs – easy glucose – no doubt but we can fuel on fat. Fat is thus the most versatile macro nutrient – usable for basal metabolic functions and/or energy.

      I’ve not seen anyone else put these things together in the way that I have done – let me know if you do. Someone else should have worked this out too!
      Very best wishes – Zoe

  13. avatar Jo says:

    Thanks Zoe for the great article, the programme wound me up too. One point about the cognitive test that the programme failed to mention and that was that Xang had recently taken a long haul flight to the U.S. and therefore would have been affected by jetlag. This would probably have affected his sleep patterns and as a result made it harder to concentrate!

  14. avatar Mary says:

    I too saw this programme and thought it very simplistic. My husband did the ‘no carb’ thing for 3 months back when it was fashionable and lost weight but of course put it all back on (and then some).

    I think Sue must be eating way more than she says (“broken cookies don’t count”) as I am 60 and 17 years post-menopause and have lost 35 pounds in a year (with a club) by dropping junk food. I do eat non-processed carbs and proteins at the same time and did not exercise nearly as much as Sue, though once the weight was lost I took up Nordic walking.

  15. avatar Isabel Natrins says:

    Thank you Zoe, as usual – a faultless critique. So glad I’m not the only one (Kate) who gets raised BP when subjected to the deluge of health ‘misinformation’ these silly, low budget programmes present as ‘science’. I’m sure the many parents who sat their carb/sugar-addicted kids down to watch were thrilled to hear the message, loud and clear: “FOLKS…SUGAR AIN’T THAT BAD!”?

  16. avatar Anne dawson says:

    Totally agree. Very weighted programme. Even I as a lay person thought it was obvious re the insulin as he hadn’t beempn eating sugar. Hadn’t realised the bod pod didn’t actually measure muscle mass, good to know.

  17. avatar Neil Ryan says:

    Response to Sue Manderville.

    Try http://www.marksdailyapple.com.

    Eating primal will show you some results.

  18. avatar Pam Forrester says:

    In your discussion of fasting glucose you indicate that the fasting glucose level has been artificially lowered in order to sell more diabetic meds, similar to the lowering of “normal” cholesterol levels in order to sell more statins.

    I have never heard the accusation about fasting blood sugar levels. From my reading it seems that the lower the better for FBG. Do you think FBG of 140 is just as safe as FBG of 95? Sorry these are American levels. I have been after my carb addicted husband to lower his FBG or his health will deteriorate. I have gotten my information mostly from Blood Sugar 101.

    I am curious as to what FBG range your research deems to be healthy. Thanks

    • avatar Zoë says:

      Hi Pam
      Good question! It’s certainly not the lower the better for any human measure (glucose, cholesterol, BP etc). We need some glucose in our blood stream or we’d be in a state of hypoglycaemia (low blood glucose). We don’t need too much or we’d be in a state of hyperglycaemia (high blood glucose). Both are unpleasant and potentially dangerous.

      I define healthy as what is normal in a normal (non messed around with) population. The link in the article shows the normal distribution of FBG levels. If I had the raw data I could work out the standard deviations to see where proportions of people fall (in a normal shaped distribution curve, 68, 95 and 99.7% of values fall within 1, 2 and 3 standard deviations from the mean respectively). Visually we can see that most people fall within the range 50-150 mg/dl. This means that it is normal for most of the population to fall in this range. My objection is when an intervention is made, following “generous financial support” from drug companies to say that normal is now deemed unhealthy. Normal for some people will be a FBG of 50. Normal for a similar proportion of people will be a FBG level of 150.

      Carb addiction is a separate, and serious, issue. The question is – what is your hubby’s normal FBG level when eating real food? And how stable does it stay (stability being arguably more important than different measurements) during the day and from one day to the next? Stable and normal may be 140 for him or 80 – don’t let drug companies tell you normal is abnormal (or, unhealthy) so that they can call someone diabetic!

      Hope this helps
      This could help with the food addiction (http://www.amazon.com/The-Harcombe-Diet-Men-More/dp/1907797122/ref=sr_1_1?ie=UTF8&qid=1391601288&sr=8-1&keywords=harcombe+diet+for+men)
      Very best wishes – Zoe

  19. avatar Ricky Knight says:


  20. avatar Carole Ruckwood says:

    Hi there! I watched Horizon: Sugar vs. Fat; it was very interesting. It concluded that neither sugar nor fat on their own make you fat but, mixed together, they do! Apparently, there are ‘cut off’ switches in your brain which tell you when you’ve had enough sugar or fat but no switch for them combined. It was also noted that nowhere in nature does this mixture exist and it only occurs in processed foods – remind you of anything? I rest my case!!!

  21. avatar Sue Mandeville says:

    Dear Zoe,…over any years I have struggled trying to find a diet that suits me after being to many diet clubs & classes, with the results of only putting on weight not ever loosing any…I exercise regularly. I watched the program me the other day and am still confused, so could you tell me if my diet is a good one . Breakfast poached egg 2 grilled bacon rashers…lunch smoked salmon 1 small Advacado lettuce tomato cucumber…evening meal eith steak or chicken salad keaves..1 piece if fruit few grapes Banana Kychee..weekends but more relaxed with a couple of glasses of wine maybe Friday of Saturday…I exercise most days…TRX…spinning….Pilates…20 20 20….but no weight loss..,any suggestions…kind regards Sue

    • avatar Zoë says:

      Hi Sue – we have known since 1917 that weight loss (through cal deficit) is invariably regained and more. It’s why the USA/UK/Aus and NZ have got bigger the more we have tried to diet. Here’s a blog on the definitive study to prove this.

      What you list looks pretty perfect – real food/managed carb intake. I suspect therefore a couple of things 1) what gets consumed when “more relaxed”! and 2) the impact of previous dieting history on your metabolism. Both are sortable – our club is here if you want help.

      Very best wishes – Zoe

  22. avatar Rosie says:

    Well they did state something of a universal truth. “six years in med school and we don’t know about this stuff” Sounds about right to me!

  23. avatar PhilT says:

    sorry that was 0.5 mmol/l (litre) not mmol/h. My ketones were higher sat watching it on the sofa.

  24. avatar PhilT says:

    The ketone data fleetingly visible on screen during the cycling segment (twice) showed a maximum concentration of 0.5 mmol/h. The carb guy was lower, of course, but with n=2 probably not statistically significant.

    I also concluded that Xand was not keto adapted, his brain ketone flux would have been much higher at 1 – 1.5 mmol.

    There is huge institutional bias in the UK – try finding a low carb dietitian on the BDA web site – only two have “carbohydrate” in their profile at all, and not in a low carb diet context. We needed two teams of experts with different viewpoints.

    The doctor who declared the muscle loss from a density measurement must be a hazard to be around, I wonder what other measurements he doesn’t understand.

  25. avatar Jessica says:

    “What is amazing is how quickly they glossed over cholesterol!”

    Yep, noticed this – so aggravating! I shall point this out to my doctor who wants me back on statins again.

    You comment on the fasting test – I’m confused by this anyway – HBA1C tests are surely done 3 months apart – that’s if your diabetes is uncontrolled. At 1 month, he is surely still recovering from the High Carb diet he was living on before.

    “[how did an exercise conclusion follow from this experiment?!]”

    I’m sure they chucked in an “exercise is important for losing weight” statement somewhere. They failed to ensure that people need to do the right kind of exercise i.e. slow, repetitive exercise, not the sort wehich puts your body into fight or flight response.

    “The body (cycling) experiment was presided over by Nigel Mitchell from Team Sky cycling.”

    Not sure why the experiment was conducted in this way anyway. It made me wince, since no sensible diabetic allows their sugars to drop to that level and then do strenuous exercise on top. I found this a highly suspect set up, and wonder if they were actually expecting the HF twin to collapse, thus showing the ‘dangers’ of a HF diet. I don’t believe any T2 following HF/LC diet would do such a bike ride without something more substantial in their pockets than 1 pat of butter. I would actually be carrying biscuits myself, out of fear of an extreme hypo. I know this relates to T2’s (I can’t comment on T1s, my knowledge is not good enough) but I don’t think either twin was doing anyone any favours.

    “that he would get bad breath and be constipated”

    Why not mention nuts? Nuts can be slotted into a low carb diet, and provide a small amount of fiber. As you have pointed out, the dangers of food passing through the body so quickly that their nutrients cannot be absorbed are probably extremely high, nuts would provide the right pace and yet did not seem to make any appearance at all.

    “Sadly Chris represents 99% of the doctors in the UK – similarly entrenched in a dangerous and non evidence based mindset.”

    Ah, I did read that slightly differently. The fact is that this current generation of doctors have indeed been trained in that mindset. The issue is that whereas we might expect to see people trusting to holistic medicines and faith healing with no evidence, when presented with facts, Doctors are the people who need to be saying, “Hold on, this jars with what we would expect to see. We should investigate”. Science is supposed to be the discipline which is excited by theories being proven incorrect.

  26. avatar Jennifer Scott says:

    Zoe. Marvelous response to BBC on our behalf, thanks.
    Having read your excellent books, along with Dr Briffa and Prof Lustig, the silly Horizon show still cast doubts in my mind that what i am doing may not be the healthy, correct thing, even though I know how well I am feeling on the regime. But, I soon overcame the doubts, and, in fact, it has made me more resolute in continuing LCHF way of eating. Not everone watching will have had the resources, or the time, to look below the superficial, and that is why Horizon must be condemned. I call it Junk Telly, in line with Junk food.

  27. avatar Patricia Cherry says:

    Thank you Zoe, Excellent breakdown from a real expert!

  28. avatar Matthew says:

    Thank you Zoe, very clear!

  29. avatar Neil Ryan says:

    I agree with everything you have put in your article. A really well written critic.

    What a waste of an hour that was watching Horizon

    my diet is based on the primal blue print style of eating (Mark Sissons – marksdailyapple.com).

    I thought like yourself that the program was stacked against Fat and probably left the public believing that a high fat low carb diet would lead to muscle waste and type 2 diabetes. Where in fact the Doctor was on a high fat No carb diet, which of course over a sustained period of time will lead to physiological insulin resistance.

    Where is Michael Mosley when you need him?

  30. avatar Stephen says:

    Thanks Zoë,
    I sat there watching and for the first few minutes I thought “this is going to be a hatchet job on fat”.
    You lose a lot of water in the early stages of any diet, and then Dr Richard Mackenzie says to Xand “You’ve lost 2kg of muscle mass and that isn’t so healthy.” I’m thinking that doesn’t sound right.
    Anyway when I’m at work the next day my colleagues are telling me how excellent the program is and “have I watched it”. I tell them there are things that are misleading (putting it mildly).
    There lies the rub, unfortunately most people rely on programs like this to be well informed and they end up being misinformed. The BBC have got to take part of the blame for the state of our nations health showing programs like this.
    Anyway thanks again Zoë for your time dealing with this. I will point my colleagues in your direction, so they can see that it was a truly poor piece of program making.

  31. avatar Matthew says:

    I’m interested in this statement:

    “It’s food manufacturers who have worked out that the sucrose/fat combo is irresistible, moreish and fattening – to rats or humans. That’s why fake food needs to be avoided.”

    So is eating carbs and fat together worse than just carbs without fat?

    The blood sugar/insulin story provides a strong causal link between eating carbs and getting fat and ill. Could you explain how fat exacerbates the problem?

    • avatar Zoë says:

      Hi Matthew
      I have advised keeping carbs and fats separate since my first publication (Why do you overeat? When all you want is to be slim) in 2004 for the following reasons:
      1) Because carbs and fat rarely occur together in real foods (avocado being the only sucrose/fat combo and nuts/seeds being the rare foods that have all 3 macronutrients in good measure). Nature tends to provide carb proteins (things from the trees and the ground) and fat proteins (things from ‘faces’) and hence we have evolved to consume carb/protein separately to fat/protein and natural eating would thus be well advised to follow this natural rule.

      2) I concluded that it would be a good idea to separate carbs and fats for weight loss based on knowledge about how the body uses different macronutrients for fuel. The body will always favour carbs for easy glucose. Hence, if any carbs are available, the body will use these for fuel and will look to store dietary fat for later on. The body needs insulin to store dietary fat and it will have insulin if carbs are available. Hence eating steak (fat/protein) with potatoes (carb/protein) creates the perfect fat storing circumstances for the body. Not good for weight loss!

      If the person instead has a baked potato with veggie (bean) chilli – they have carbs/glucose to use for energy and virtually no fat to store for later on. The body will clear some glucose into glycogen; use some glucose straight away and then likely call back upon the glycogen if enough time is left between meals (I also do NOT favour grazing!)

      If the person has steak with salad – the carb intake is negligible and the body can use dietary fat for fuel. Insulin impact is also negligible and thus there is no fat storage scenario for the body and the body happily fuels on fat.

      People following The Harcombe Diet know this as the ‘no mixing’ rule and it seems to work well!
      Hope this is of interest
      Best wishes – Zoe

  32. avatar Lucy piper says:

    A brilliant well argued response. I also can no longer watch these programmes or even talk to people about them as I get too angry, and don’t want to be producing all that nasty cortisol!!! I will quietly point them to this article instead. Three years ago this month I started Harcombe and it has changed my life forever.

    Thank you Zoe

    Lucy Piper

  33. avatar Phil says:

    Excellent response to a very dangerous and misleading programme,considering these people were medically trained professionals?.As regards the BBC it has not been balanced for some considerable time.I hope I live long enough to rejoice the ending of the TAX on all, that is the licence fee.

  34. avatar Tom Welsh says:

    I resemble your suggestion that the BBC is “not balanced”. On the contrary, as I see it the BBC always balances the interests of the rich very scrupulously against the interests of the powerful.

  35. avatar Kate Holland says:

    Bravo, Zoe! I no longer watch these shows as they make my blood pressure go up! I read you and Dr.Briffa instead!

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