SACN report: Carbohydrates & Health
On Friday 17th July 2015, a report was issued by the Scientific Advisory Committee on Nutrition (SACN). This report was initiated seven years ago: In 2008, the Food Standards Agency and the Department of Health asked SACN to provide clarification of the relationship between dietary carbohydrates and health and to make public health recommendations.
Terms of reference
The Terms of reference of the working group were four fold. “To review:
1) the evidence on dietary carbohydrate and colo-rectal health in adults (including colo-rectal cancer, irritable bowel syndrome, constipation) and in childhood and infancy;
2) the evidence on dietary carbohydrate and cardio-metabolic health (including cardiovascular disease, insulin resistance, glycaemic response and obesity);
3) the evidence on dietary carbohydrates and oral health;
4) the terminology, classification and definitions of types of carbohydrates in the diet.”
It would have been far better to give an independent panel (we’ll come to conflicts) a free remit on food and health and then they may have been able to spot a connection between the change in dietary guidelines (1983 UK) and the concomitant epidemics of obesity and diabetes. They may also have been able to look at recommended micro nutrient intakes and worked out that the most nutrient dense foods are not ‘healthy whole grains’.
Overall summary and conclusions
Chapter 12 has the overall summary and conclusions. You can look at the whole report yourself. I’ve extracted key conclusions on carbohydrates and the health measures that fell within the terms of reference. The summary is presented for: total carbohydrate; sugars and sugar-sweetened foods and beverages; starch and starch rich foods; and dietary fibre.
Total dietary carbohydrate
12.8 “Overall, the evidence from both prospective cohort studies and randomised controlled trials indicates that total carbohydrate intake appears to be neither detrimental nor beneficial to cardio-metabolic health and colo-rectal health.”
i.e. we spent seven years looking at evidence on carbohydrates and we can’t say that it’s harmful or helpful. That’s quite funny – unless you’re the poor sod who funded all of this. Hang on a sec – that’s me, as a UK taxpayer!
Sugars and sugars-sweetened foods and beverages
12.9 “Prospective cohort studies indicate that sugars or sugars-sweetened beverage intake is not associated with the incidence of colo-rectal cancer. There is no association between the incidence of type 2 diabetes mellitus and total or individual sugars intake, but a greater risk is associated with a higher intake of sugars-sweetened beverages. There is insufficient evidence to enable conclusions to be drawn in relation to cardiovascular disease endpoints.”
i.e. observational studies clear sugar of all charges except that sugary drinks are associated with type 2 diabetes.
12.10 “Trials examining cardiovascular risk factors, inflammatory markers and risk factors for type 2 diabetes mellitus demonstrate no effects of increasing sugars intake. There is also insufficient evidence to assess the link between individual sugars and sugars-sweetened foods and beverages and cardiometabolic outcomes.”
i.e. what trial evidence we looked at clears sugar of all charges.
12.12 “Overall, there were very few studies on individual sugars, such as glucose, fructose or sucrose, which met the inclusion criteria for this report. Prospective cohort studies indicate that higher consumption of sugars and sugars-containing foods and beverages is associated with a greater risk of dental caries.”
i.e. there isn’t much evidence on sugar (that’s because research is funded where it can benefit the funder; the government should fund research into the health effects of sugar, but it doesn’t. It funds seven year coffee meetings instead!) The worst we can find is that sugar is bad for teeth. The latter was firmly established in the 1983 National Advisory Committee on Nutritional Education (NACNE) report, so there’s nothing new here.
Starch and starch-rich foods
12.13 “Prospective cohort studies indicate no association between starch and refined grain intake and cardiovascular disease endpoints and type 2 diabetes mellitus. There is a lack of evidence relating colo-rectal cancer and oral health to starch and starch-rich foods intake. There is insufficient evidence to draw a conclusion on the association between starch intake and weight gain.”
i.e. starch and even refined grains are also cleared of all charges. We don’t have evidence for starch and weight gain, so we have to let starch off for that one as well.
12.15 “Prospective cohort studies indicate that a diet rich in dietary fibre is associated with a lower incidence of cardiovascular diseases, coronary events, type 2 diabetes mellitus and colo-rectal cancer.“
i.e. we’ve seen an association between fibre intake and lower incidence of the conditions we were asked to look at. However, cohort studies can only suggest association – Randomised Controlled Trials are needed to show causation. And…
12.16 “Randomised controlled trials indicate no effect of (total, mixed) dietary fibre intake on cardiovascular or type 2 diabetes mellitus risk factors considered in this report.”
i.e. … proper intervention trials showed nothing. Zippo. Zilch.
12.19 “Overall, randomised controlled trials in adults indicate that supplementation with non-digestible oligosaccharides improved blood lipid concentrations, increased faecal mass and bacterial content. Resistant starch supplementation increased faecal mass and short chain fatty acid content. Polydextrose and polyol supplementation increased faecal mass.”
i.e. giving adults things that they can’t digest generates lots of poo.
I’ve not listed all recommendations. Because the fourth term of reference was about terminology and classification, some of the recommendations are about terminology and classification and this is pretty dull.
S.16 “It is recommended that the dietary reference value for total carbohydrate should be maintained at an average population intake of approximately 50% of total dietary energy.”
i.e. despite the fact that even an active person only needs c. 25% of their intake in the form of energy and that this can come from carbohydrate OR fat, we recommend that everyone has half their intake in the form of the only macronutrient for which we have zero requirement: carbohydrate.
S.18 “It is recommended that the average population intake of free sugars (Defined at end – Ref 1) should not exceed 5% of total dietary energy for age groups from 2 years upwards.”
i.e. people should have no more than 5% of their dietary intake in the form of sugar but, because all carbohydrates are, or break down into, sugar they should have 50% of their dietary intake in the form of sugar (S.16).
S.22 “It is recommended that the dietary reference value for the average population intake of dietary fibre for adults should be 30g/day.”
i.e. there is no evidence for the current recommendation of 18g/day but we will increase this substantially to another number for which there is no evidence: 30g/day. (There is big love for fibre emanating from this 384 page document – the word “fibre” appears 717 times. They clearly haven’t read “Fiber Menace”).
S.23 “It is recommended that the average population intake of dietary fibre for children aged 2 to 5 years should approximate 15g/day, for children aged 5 to 11 years 20g/day, for children aged 11 to 16 years 25 g/day and for adolescents aged 16 to 18 years about 30g/day.”
i.e. we’ve made up numbers for adults so why not make them up for children and teenagers too. Good luck parents with your little darlings literally full of [email protected]
Background on health outcomes (disease prevention)
Chapter 4 shares the headlines of what the committee (in various forms – people came and left over seven years) learned about each of the conditions they were asked to look at:
4.3 notes that atherosclerosis is influenced by elevated blood glucose. And what elevates blood glucose? Try carbohydrates.
4.5 shows the belief system held by the committee about obesity – not the insulin/hormone model of the thinkers in this field, but the classic greed and sloth model: “Obesity occurs when energy intake from food and drink consumption is greater than energy expenditure through the body’s metabolism and physical activity over a prolonged period, resulting in the accumulation of excess body fat.”
Type 2 diabetes
4.7 “It is important to identify which dietary aspects improve glycaemia, insulinaemia and insulin resistance in individuals with normal or moderately compromised glycaemic control to further elucidate the role of diet in the prevention of type 2 diabetes mellitus.”
It is important to identify!? I thought that was the committee’s job? I think you’ll find: dietary fat has no impact on blood glucose or insulin; protein has no impact on blood glucose and carbohydrate wrecks havoc with both blood glucose and insulin.
The learnings here were presented in seven sections (4.8-4.14) – not one of which mentioned carbohydrate or sugar. Fibre was mentioned only once – in the context of “an intake of about 25g/day dietary fibre” will help defecation.
About the worst they could say was (4.16) “Sugars in the diet exert an effect after eruption when the teeth are exposed to the oral environment.” Whatever that means.
The conflicts of interest among panel members long preceded this report. Channel 4 ran a programme on the 20th January 2014 highlighting the food industry funding received by “the chief scientist looking at the sugar question” – Professor Ian MacDonald of Nottingham University. Channel 4 Dispatches discovered that since 2012 he had resumed working for two food and drink giants: sitting on two advisory boards for Coca Cola and one for Mars. As the programme released noted: “He also receives funding from Unilever which is the world’s largest ice-cream manufacturer.”
Hannah Sutter did a fuller expose of other committee members here. Notice Jordan cereal – they’ll love the fibre love-in. Mars and Coca-Cola will be really happy that sugar has largely been exonerated and Sainsbury’s will be happy that 80% of the current aisles have been given a health tick.
You’ll have to search hard for the declared conflicts. I asked Public Health England and was directed to the annual report. Check out Annex 5.
The SACN report has a preface by Dr Ann Prentice, Chair of the Scientific Advisory Committee on Nutrition. Here are her declared interests. I’ve highlighted a few:
Action Medical Research; Aarhus University Hospital; Aquapharm; Arch Timber Protection; Boden Institute for Obesity; British Dietetic Assoc; BUPA Treasury; Cambridge University Hospitals; Christie NHS Foundation Trust; Coca Cola; Cranfield University; Danish Brewers’ Association; Diabetes UK; Electro Sci. Industries; European Molecular Biology Laboratory; HS Pharma; Institute of Brewing and Distilling; Ikon Informatics; Iron Therapeutics Switzerland AG; Kellogg Company; King’s College Hospital LLR-G5 Limited; National Safety Assoc; National Centre for Social Research; Nestle; Playerthree; Shield Holding AG; Thermo Fisher Scientific; Weight Watchers Int; World Cancer Research Fund; The Rank Prize Funds; Thrombosis Research Institute; UCL Consultants; Universitat Rovira; Weight Watchers; York Teaching Hospital NHS Foundation Trust; pSiMedica.
(I find myself wondering if any of those make toilet paper!)
My first and lasting thought is – why did this take seven years and 384 pages? It takes fewer than seven seconds and three words to issue sound dietary advice: “Eat real food!” (“All-bran doesn’t count”, may be helpful in the circumstances).
My other key points are:
1) All carbohydrates are, or break down into, sugar. The report is littered with the words monosaccharides (saccharide meaning sugar), disaccharides (sugar), polysaccharides (sugar), fructose (sugar), glucose (sugar), maltose (sugar) … They must know that they are talking about sugars all the time – just sugars in different forms. Yet, the key recommendations can be summarised as “eat less sugar and eat more sugar.” I just don’t get it.
2) There is no evidence for any of these recommendations:
– 50% of the diet in the form of carbohydrate sugars – why? Why not 5%? Why not 95%?
– 5% of the diet in the form of free sugars – why? Why not 10%? Why any?
– 18g of fibre had no evidence; 30g has no evidence. Why 30? Why not 10? Why not 50? Why not just tell people to eat food for the micronutrients they need and then fibre won’t get a look in?
3) The sugar industry could barely have dreamed of such a favourable report, but then when your chair of the SACN and your chair of the SACN carbohydrate working group are/have been funded by Coca-Cola and Nestle and Coca-Cola and Mars respectively, the sugar industry should never have been that worried.
Ref 1: S.17 gives the definition of free sugars as: “It is recommended that the definition for ‘free sugars’ be adopted in the UK. This comprises all monosaccharides and disaccharides added to foods by the manufacturer, cook or consumer, plus sugars naturally present in honey, syrups and unsweetened fruit juices. Under this definition lactose when naturally present in milk and milk products is excluded.”
p.s. (This was the Monday newsletter for 20 July 2015)
40 thoughts on “SACN report: Carbohydrates & Health”
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I saw a couple of very interesting videos on TED that tied brain development with fire and meat as a way of significantly increasing our cognitive abilities. If the hypothesis is correct then we are human because we used fire to cook meat and have done so for a couple of million years.
On the other hand the initial increase in carbohydrate availability came with agriculture about 10,000 years ago. It should be noted that in some parts of the world even farming hardly produces enough for the development of settled villages.
And of course the age of sugar and excess carbs is only just with us.
Found recently on a blog, a study purporting to show the harmlessness of fructose.
The study itself is behind a paywall but the Conflict Of Interest isn’t.
Amazing work again Zoe (you’re probably bored of the accolades now?!)
Do you ever worry that the advice you give, ie eat your meat and drink your milk, is rendered completely null and void by the horrific state of the meat and dairy industry in this country?
I know you often prefix steak with ‘grass fed’, but it’s my understanding that due to the use of Bovine growth hormones and homogenisation (even pasturisation) commercial milk is not only nutritionally void but possibly carcinogenic. (I’m not vegan or even veggie by the way!).
More of the gathering, less of the hunting? Not to mention the acidying effects on the body of meat, fish and dairy?
Because of some good news recently, I began to think that nutritional advice from governments and associations was going to start changing at a fast pace. That is until I read your article and saw the video about low carb diets from the tv show ‘Extreme Weight Loss’. http://abc.go.com/shows/extreme-weight-loss/news/updates/05272015-high-fat-low-carb-vs-high-carb-low-fat-diet-experiment
I find it hard to believe people can lie so blatantly. In the show, the guy is on a low carb diet (who knows what that means to them?) for 65 days and is still tired and can’t summon the energy to do a full workout. How did they get him to lie so blatantly? These low fat jerks have no morals.
Thanks Zoe for helping fund a study that reassures us that the first law of thermodynamics is true even in humans. “Obesity occurs when energy intake from food and drink consumption is greater than energy expenditure through the body’s metabolism and physical activity over a prolonged period, resulting in the accumulation of excess body fat.” That is truly a valuable service. I think many under the age of 10 needed that reassurance.
However much money they spend “proving” it still doesn’t make it true! Hormones (mainly but not exclusively insulin) shunt food into store as body fat and prevent it being metabolised, so you then have to eat more food to meet your metabolic needs. Rinse and repeat. Only when insulin levels are reduced does the stored fat become available again. Calories in = calories expended PLUS calories stored.
Well, to be clear, maybe excessively clear, they did correctly state the first law of thermodynamics. The trick of course is that they said it with more words than you did with formula: calories in = calories expended plus calories stored.
The sad point is that they say calories in, calories out. That is shorthand for any calories in will cause the same weight gain and any calories out is caused by exercise. That is not true for the reason you explained so well. Though I would add that one would not only eat more with a high carb diet, but would not feel like moving as much because your body is hungry.
Precisely what happened to me! I was sort of holding my own, in terms of not getting worse, until I met a dietician, then I went downhill fast.
The major problem is that this doesn’t happen to EVERYONE, so Conventional Wisdom claims therefore it happens to NO-ONE.
A minority of the population appears to have adapted to high carb low fat – though whether that adaptation remains as they age seems doubtful. It’s been suggested that everyone will eventually become diabetic, but for some this will not occur until age 150 by which time they will have died of something else. Metabolically it appears that old age is becoming ever younger: not only pancreases are wearing out much earlier in life since low fat diets were championed but probably mitochondria too.
The good news is that ever more researchers, including people no-one has ever heard of before, are rejecting Conventional Wisdom and looking at what’s really occurring. The bad news is they are still outnumbered by people desperately trying to assure their ongoing research funding by backing CW, and this report shows clearly which “side” supplies the “evidence” fed to doctors as well as the general public.
You, me and millions of others are “just anecdotes”.
The first law is always true in any application until you find an exception where it is not. Of course the second law is also true until you find an exception where it is not. Unfortunately, the diet industry is running for the most part on the concept of a perpetual motion machine (calories in equal calories out), which the first law allows (conservation of energy), but the second law does not (it takes energy to make energy). It is remarkable how so much money could be made on a scam (denial of the second law).
Thank you ever so much for all you . You may be interested in reading an article by Mark Hyman from the Huffington Post called ‘ Eggs don ‘t make you fat – sugar does ! ‘.
I find “studies” like that annoying. I am thinking that perhaps the best way would be to suspend or retire most or all publicly-funded medical researchers and their institutions, and start all over. Perhaps setting up a non-profit organization towards that objective might work? Regards,
Thanks Zoe another stunning post from you, but I would not expect anything less from you.
Keep up your great work, people are getting the message big time.
Kind regards Eddie
This is so disappointing but expected. My main concern is for children and hospital patients who will continue to receive low nutrient food in our schools and hospitals which is in line with these industry sponsored guidelines. It’s a scandal.
Thanks for the update Zoe
“giving adults things that they can’t digest generates lots of poo”
yes 384 pages of it!
Ye Gods, these people come from a planet where Gerald Reaven, Ron Krauss, Eric Westman, Jeff Volek, Stephen Phinney, Richard Feinman etc. never existed, let alone Weston A Price, John Yudkin, T L (Peter) Cleave, William Banting, Robert Atkins et al.
Should I bother reading this crap, or just print it out and use it to wipe?
NO! Please do not pollute the planet further by printing it out. Besides it would tear that part of your anatomy to shreds and would not biodegrade. You left out George V. Mann! 384pages? Really? Got to go! I feel a disturbance in ‘the force’
12.19 Giving adults ‘7 years to provide clarification of the relationship between dietary carbohydrates and health and to make public health recommendations’ generates lots of poo!
Ha ha got it! This report is the research equivalent of dietary fibre.
So seven more years of generating more and more highly profitable obesity and diabetes and premature death from CVD (which is profitable to the pension industry). Then distract the attention of the public on to cancer, see today’s TV news. Has there been any coverage of this in the media? One could hope Aseem Malhotra or one of the other clueful high profile doctors might comment.
slowly by degrees they are proving atkins right. But of course the economy is in a mess ( for some anyway ) so they wont jeopardise productivity by slamming grains or the other products that are big earners ………… will they!!
I know from experience that dumping the carb lifestyle can bring big changes certainly as a t2 my spec nurse now looks at me a bit different from most of her patients. I think because she dosnt see me as often as most.
Dr David Unwin reports saving £15 000 – £30 000/year from giving his diabetics a low carb diet
imagine if more GPs did this it would break the economy
I echo the kudos to Dr Fung…I believe in low carb whole food, but it was adding fasting to my way of life that really ramped up my progress. I used to believe in the idea of eating frequent small meals to keep insulin levels even, but once I watched Dr Fung’s video series, I could see that instead of keeping them even I was keeping them elevated. I added IFing to my way of life (I eat 2 meals every day and nothing in between…ever) and my personal results have delighted me! I won’t go into the details as this post is already getting long enough, but I will say that as a mid-fifties post-menopausal woman, I am at a weight that I think is right for me for the first time since puberty…and have achieved some other health gains by giving up Industrial-Foodlike-Substances.
I send people who ask how I’ve achieved my goals to Dr Fung’s blog, but I also send them to yours and Andreas’ and the other sane voices in the midst of the sugar-fuelled insanity! You were one of the voices who (finally!) set me on the right dietary path, and I bless you all for putting the word out there, so that when we finally realize what we’re doing is wrong and go searching for the answer, the answer is there to be found.
Thank you and bless you!!
I’ve never deliberately fasted – it happens automagically. On my old low fat diet I would need to eat every couple of hours to avoid hypoglycemic crashes. Now on a low carb/paleo/real food diet I routinely go 6 – 8 hours and often longer without feeling any desire to eat. In my case I’m certain it’s the effect on glucose and insulin levels that does this, satiating food doesn’t spike either. I deliberately set out to reduce postprandial glucose spikes
my trigs/HDL ratio, an indicator of insulin resistance, went from nearly 7 to generally under 1. This is commonplace on diabetes forums but unknown to most doctors.
Oh and I crap just fine despite no wheat and very few Healthy Whole Grains. Which reminds me . . .
Many thanks for all your comments – I do enjoy and appreciate them :-)
Good point on the fasting – it just happens with low carb. You just find you’re not hungry and blood glucose levels are nice and stable and energy is great. Anyone who tries it would stick with it for health – the weight is just a bonus!
Best wishes – Zoe
And thank YOU for your blog, which I only recently discovered, I think via
and have read from end to end
“Sugar (da da da da da da) oh, honey, honey. You are my candy girl, and you’ve got me wanting you”. This could perhaps be this “working group’s” theme tune!!! You really couldn’t make it up, Zoe, could you? I read your analysis with shaking head and open jaw. The conflicts of interest are outrageous, in my opinion, yet no doubt all of this will now be littered across the media as “proof” that carbs are what we should all be eating, just not the ones that are obviously “sugar”…..
I’d like to propose a change to this: “I think you’ll find: dietary fat has no impact on blood glucose or insulin; protein has no impact on blood glucose and carbohydrate wrecks havoc with both blood glucose and insulin.”
Fat, carbs, and protein all cause an insulin response. Carbs >>>>> protein >> fat, but they all three cause an insulin response. Too much protein can technically cause a glucose rise.
The reason I know this is the following. I went on a very low carbohydrate diet and did lose some weight, about 20 pounds (US, say 10 kg in metric), but I stopped losing and basically lost weight very slowly. I did research on insulin resistance and determined I was insulin resistant. I was eating 5-6 times a day, as I was supposed to according to the experts. I started intermittent fasting (in combination with my low carb diet) and the weight has literally flown off me. In 1.5 years, I lost 20 pounds on low carb; in about 5-6 months of intermittent fasting and low carb, I’ve lost 20+ pounds, so about three times the rate of weight loss with the latter than the former. I also now concentrate on upping my fat content when I do eat.
I recommend all of the videos by Dr. Jason Fung. He’s convinced me that insulin resistance is very important. For those of us with high insulin resistance, low carbohydrate diets help. However, fat and particularly protein cause an insulin response, and eating too many times a day exacerbate this. For those of us with high insulin resistance, we have to break our insulin resistance, and fasting is one way to achieve this. Low carb helps, but for some of us, it doesn’t help as much as one would think it should.
Actually, it was about a year of low carb to lose 20 pounds and 5-6 months of IF+low carb to lose another 20 pounds. So, about double the weight loss with IF+low carb.
I’m interested in this because I had the debate with Jason in May this year. Please do you have evidence for fat (pure fat) causing an insulin response?
Best wishes – Zoe
p.s. I had the joy of presenting with Jason in SA in Feb so saw the videos you’re talking about ‘live’
I *think* the point Dr.Fung makes is that 5-6 meals a day is an excessively repetitive stimulus received by your body telling it that there’s a great deal of energy available – independent of the post-prandial blood insulin response.
Indeed, fat creates essentially no post-prandial blood insulin response. However, insulin is still the major shuttle delivery hormone for energy into tissues. So despite their being insulin-dependent and non-insulin dependent transport mechanisms for fat/carbs/protein (i.e. need for redundancy) into cells, fat still exploits basal insulin levels to get the ‘go ahead’ for getting into cells. For e.g.,”[FATP1 = fatty acid transporter protein 1] translocates from an intracellular compartment to the plasma membrane in response to insulin”
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1447434/. If not, people would waste away on ketogenic diets (and they clearly don’t!). Insulin is not the only checkpoint – I’m simplifying.
As @JimJohnsonSci points out, it isn’t even yet know at how many different levels insulin sensitivity/resistance occurs: is the density of cell-surface receptors? Is it responsiveness to intracellular (i.e. downstream) signalling? How does the transcription respond to the upstream input?
Zoe, I do not. All I have is information from Fung’s videos. Unfortunately, I’ve watched at least 7 of them, so it’d be hard to pinpoint where he says this. They also are quite long, an hour or so each. Additionally, it might be difficult, even if I found the location, to give you a citation, as he might not give enough information to determine the study or studies he’s using.
I’ll try to find it, though.
However, this says “fat does not stimulate an insulin response at all”:
If there is an insulin response due to fat, I think the insulin response due to fat is small. That’s not too concerning to me. What’s more concerning is the insulin response due to protein. I would exercise and afterward eat three eggs, plus meat and a slice of cheese. That’s a lot of protein, and I’d eat 5-6 times a day, each time with protein. Was I eating too many calories and that’s the reason I was only slowly losing weight on low carb? It’s unclear. All I know is that since starting IF, I’m not as hungry. Also, if I eat breakfast, I eat the same amount for lunch as I do if I skip breakfast. I’m just as hungry at lunch whether I eat or skip breakfast. And — oddly enough — I feel better not eating breakfast, even if I workout in the morning.
Anyway, since I’ve realized that nothing I thought was true actually is true, I don’t believe anyone anymore, including Dr. Fung (and you ;-). Dr. Fung I find can use epidemiological evidence to bolster his arguments, and as we know epi evidence only proves correlation not causation. From that perspective, his conclusions are questionable.
However, his theory of insulin resistance for me answers many questions I had and makes sense. For instance, when I was on relatively high carb and riding my bike 100+ miles a week, I lost some weight, mainly because I physically was not hungry. My theory is that I’d changed my insulin resistance enough to cause me to no longer be hungry. Why does the fat fast work? Probably because it lowers insulin and insulin resistance. (Same for low carb) Does obesity cause insulin resistance, or does insulin resistance cause obesity? All the experts believe the former; Dr. Fung believes the latter, and the latter makes perfect sense to me.
Could Dr. Fung be wrong? Absolutely. In my case, however, IF has been a godsend and many things Dr. Fung says about fasting (causes a decrease in appetite, you’re not hungry even though you’re not eating, you have more energy when fasting, you do not lose muscle mass and instead gain muscle mass, and eating breakfast causes you to eat more in a day) are true for me personally. I firmly believe in LCHF, but I also believe in IF. I won’t go back to eating 5-6 or even 3 meals a day.
Having had the discussion with Jason, I think we’re all of the same view as the link you provided – fat does not stimulate an insulin response. The possible confusion may arise from the famous Holt 1997 paper (http://ajcn.nutrition.org/content/66/5/1264.abstract
http://ajcn.nutrition.org/content/66/5/1264.full.pdf) which looks at foods that are high in fat, but doesn’t test fat alone (which would have to be lard or an oil – even butter has a protein content).
You are right, with Jason’s brilliant guidance, to spot the protein impact and the harm of having so many occasions of eating per day (as our dear dieticians advise – someone sue them!)
Jason is one of the few people I trust to be right. You’re right not to trust anyone though – one’s own questioning and researching mind will do very well.
Best wishes – Zoe
http://caloriesproper.com/insulin-dietary-fat-and-calories-context-matters/ has some insulin response to fat(s) data (small).
Zoe, you are absolutely correct. He has a video called Trial by Diet, which you can see here:
If you download the slides, on slide 41, entitled “Fat raises insulin levels”, he cites to Am J Clin Nutr l997;66: 1264-76 Holt SH. If you download this from here:
You realize that they test foods, but never test fat by itself. The foods have differing amounts of fat, but fat itself is never tested. The tables do not support the statement that fat itself raises insulin.
They’re also a bit confusing. Perhaps they do support his contention, though. Peanuts have an insulin score of 20 (low), but cheese has an insulin score of 45. Peanuts are 20.1, 9.6, and 5.4 (grams of fat, protein, carbs), and cheese is 20, 15, 0.1. If you assume fat contributes zero to the insulin score, then peanuts it seems to me should have a similar insulin score to cheese, as the total protein + carbs are about the same (and if carbs are worse than protein, then peanuts should have an insulin score higher than cheese). So maybe fat does contribute to insulin release.
Of course, this analysis ignores the different proteins between peanuts and cheese, and these proteins do affect insulin response.
Unfortunately, in my opinion, this paper doesn’t really answer the question of whether fat contributes to an insulin response. If they would’ve used butter or coconut oil or lard, etc., we’d have a clearer picture.
That’s the discussion Jason and I had and we’re all in agreement that there’s no evidence that fat elicits an insulin response. Fat rich isn’t fat alone.
This just happened to be one of my pet peeves – when documentaries say they’ve given someone a fat breakfast and then measured lipids, I’m the one screaming at the TV! They have invariably offered bacon, sugary baked beans, hash browns, eggs of some kind – all three macronutrients and all three fats (sat, mono, poly). Then they try to blame (sat) fat for anything they find!
We need to test things individually: the only pure carb is sugar (sucrose); the pure fats are lard/oils; there is no pure protein (protein is in everything other than sucrose and oils/lard) – but egg whites/white fish approximate to pure protein. I was planning to do this for my PhD but then became more interested in dietary guidelines.
Best wishes – Zoe
Yes I think the confusion comes from the infamous “pizza effect” where the high fat slows the conversion of the high carbs into glucose. A Type 1 diabetic using fast insulin may go hypo as the insulin outruns the carbs, and then go hyper sometimes for a few hours as the glucose continues to trickle in after the insulin is finished. The total requirement for insulin is the same, only its distribution over time varies. This can be overcome by using a partial bolus with/after the meal and giving the rest of the bolus later, or using sophisticated pump functions.
Some Type 1s find R, which is somewhat slower, better matches a low carb high fat diet – the current bolus insulins are designed for use with a high carb low fat diet.
Some Type 2s with a broken first phase insulin response but still good phase 2 insulin can handle the combination of fat and carbs much better than the carbs on their own, a useful trick when eating out provided you don’t do it too often.
Bob, I always appreciate your measured, well informed and well-written contributions. However, I’ve never read or heard that fat has any significant effect on insulin. Indeed, I’ve consistently heard the opposite from, for example, Wendy Pogozelski, professor of biochemistry and Dr Sarah Hallberg. Can you clarify, please?
Haven’t digested it yet (no pun intended) but aren’t they advocating a change of analytical method for fibre which will give us about half the increased recommendation for free.
Hi Phil – yes is the short answer!
S.22 : “It is recommended that the dietary reference value for the average population intake of dietary fibre for adults should be 30g/day, as defined in the paragraph
above and measured using the AOAC methods agreed by regulatory authorities. The previous dietary reference value of 18g/day of non-starch polysaccharides, defined by the Englyst method, equates to about 23-24 g/day of dietary fibre if analysed using these AOAC methods, thus the new recommendation represents an increase from this current value.”
Best wishes – Zoe
And there was I eagerly awaiting this report, which would surely condemn sugar/carbs, only to discover that finally, after 7 hard years of intense research by independent experts, that you, me and all our friends who also study nutrition, are wrong after all. Duh! Clearly, we’ve been researching the wrong evidence. The global obesity epidemic must be due to a sudden explosion of greed and laziness, particularly amongst children (I blame CBeebies), and nothing at all to do with the massive consumption of sugar in all its disguises and we can carry on eating/drinking manufactured, processed foods as Nature intended (or not) – so long as we don’t mind our teeth rotting and falling out. A good [email protected] every morning and we’ve nothing to worry about. (I haven’t read the whole report yet Zoe, but I know it’s going to make my blood boil!! I knew this would happen having read the short SACN interim reports. What a whitewash!…and a tragedy. In the meantime 100s of thousands of people will suffer from the utter misery of diseases directly caused by sugar. It’s sickening.) Keep up the good work Zoe.
Dr Paul Travis, could I recommend that you do not read the whole report. A mere thought of you ‘sickening’ and ‘blood boiling’ inspires my caring nature to call out for you to ‘protect yourself from serious mental (and possible) harm’.
Tell me instead to get my books written, for the world’s people sure need to keep hearing and seeing the ‘correct’ information.
Did it take them 7 years to do this? 7years? … trust me don’t read it … save yourself the pain :) Sigh… so don’t telling people
‘you weren’t warned if you do read it!’