A post that is likely of more interest to my Kiwi viewers, but one which happens all too often right around the world, and an example of why we need to be just a little careful at taking health authorities at face value.  This post also serves as a bit of a “please explain”.  “Please explain” is a question I’ve been intent on asking following this article late last year on high-sugar muesli bars getting the Heart Foundation tick.  Firstly, I wanted a “please explain” from the dietitian claiming that muesli bars were a “sometimes food”.  Could she (or anyone else) please explain just what “sometimes” means.  Can I sometimes have them everyday? Or is it something I have once per week, month, or year?  “Sometimes” just seems a little to nebulous for my liking.

But the real “please explain” in that piece belongs to the Heart Foundation’s Tick Manager, Deb Sue, for this statement;

The amount of sugar is not considered because there was “no scientific evidence that sugar causes heart disease”.

Now one would think that the New Zealand Heart Foundation would have its fingers on the pulse in terms of keeping up with published research in this area, particularly New Zealand research.  In 2010, NZ epidemiologist Simon Thornley published his “New Zealand sugar (fructose) fountain: time to turn the tide?” paper in the New Zealand Medical Journal.  In this paper, Simon draws some relatively vague links to heart disease.  But he follows this paper up with a publication (just prior to Ms Sue’s unfortunate comments) which specifically tackles the heart disease risks of a high sugar diet.

Sugar restriction: the evidence for a drug-free intervention to reduce cardiovascular disease risk.

We found relatively consistent evidence of association between markers of sugar intake and risk factors for cardiovascular disease, or the disease itself. This evidence contrasted with rather weaker evidence which linked either saturated fat or salt with cardiovascular disease endpoints. We also found some evidence of a sugar addiction syndrome.

We suggest that advice to restrict sugar intake should be a routine part of clinical care, particularly when patients are being counselled about cardiovascular risk.

That last line from the conclusion is particularly interesting when you contrast that against what the New Zealand Heart Foundation are all about…

The Heart Foundation is New Zealand’s heart health charity. We fund research and promote heart health, helping New Zealanders to live fulfilled lifetimes. We are steadfast in our goal to stop New Zealanders dying prematurely from heart disease.

Looks like someone in the NZHF might want to give their Tick Manager that memo, along with a copy of the above study to read, just in case she decides to go shooting misinformation from the lips regarding sugar and heart disease in the future.  Though I am picking, as Tick Manager, her KPI’s are slightly different to “stop New Zealanders dying prematurely from heart disease”.

The most recent example of public misinformation from a supposed health authority comes from NZ television’s best known dietitian for hire – Claire Turnbull.  Here are just a few examples of the types of healthy food ideas Claire likes to beam into our living rooms…

Cereal -

More cereal -

Nut bars -

Juice -

In case you are interested, here is the ingredients of Hubbards Big Breakfast….

Rolled Oats, Flaked Red Wheat, Sugar, Fruit (Sultanas, Dried Apple, Pineapple, Papaya, Coconut), Multigrain Flakes (Wholegrain Wheat, Wholegrain Wheat Flour, Corn Flour, Rice, Sugar, Barley Malt Extract, Salt, Emulsifier [471]), Oat Flour, Natural Sliced Almonds, Rice Pops, Maltodextrin, Canola Oil, Pumpkin Seeds, Caramelised Sugar Syrup, Salt, Cinnamon, Flavour, Preservative (220)

And Quaker Bars (They’ve got the tick!)…

GRANOLA (WHOLE GRAIN ROLLED OATS, BROWN SUGAR, CRISP RICE [RICE FLOUR, SUGAR, SALT, MALTED BARLEY EXTRACT], WHOLE GRAIN ROLLED WHEAT, SOYBEAN OIL, DRIED COCONUT, WHOLE WHEAT FLOUR, SODIUM BICARBONATE, SOY LECITHIN, CARAMEL COLOR, NONFAT DRY MILK), CORN SYRUP, SEMISWEET CHOCOLATE CHIPS (SUGAR, CHOCOLATE LIQUOR, COCOA BUTTER, SOY LECITHIN, VANILLA EXTRACT), BROWN RICE CRISP (WHOLE GRAIN BROWN RICE, SUGAR, MALTED BARLEY FLOUR, SALT), SUNFLOWER OIL, OLIGOFRUCTOSE, POLYDEXTROSE, CORN SYRUP SOLIDS, GLYCERIN. CONTAINS 2% OR LESS OF WATER, CALCIUM CARBONATE, INVERT SUGAR, SALT, MOLASSES, DIACETYL TARTARIC ACID ESTER OF MONO-DIGLYCERIDES, SUCRALOSE, NATURAL AND ARTIFICIAL FLAVOR, BHT (PRESERVATIVE), CITRIC ACID.

Mmmm… that just looks so heart healthy, doesn’t it.  You can see why it got the tick.

SIDEBAR: Let’s say you want to give your kids a healthy start to the day, and you follow the helpful and authorative advice of our dietitian-for-hire (you appreciate her taking time out of her busy day to bring you these public service announcements).  You start your kids with the Hubbards Big Breakfast cereal and a glass of the Just Juice Vegetable Juice.  You also pack a couple of the Quaker bars into their lunch box for the day’s snacks.  You can see the ingredients you are tipped down your child in the examples above… but we care not about ingredients – it is the healthy numbers we market things on.  Let’s pick on one of those numbers – sugar.  Just how much sugar are you giving to your kids based on Claire’s recommendations?

• Hubbards Big Breakfast – for a suggested 50g(!) serve = 10g of sugar*
• Quaker Granola Bars (25% less sugar) – a small 24g bar(!) = 5g of sugar*
• Just Juice with Veggies (40% less sugar than regular Just Juice – 250ml glass = 15g of sugar**

The total amount of sugar consumed, just from these three examples, for your child, is ~30g of sugar per day.  From the NZMJ piece of New Zealand’s sugar fountain – “…less than 40g a day (about one and a half tablespoons) are recommended by the World Health Organization to prevent dental caries, obesity and chronic disease.”

*These are very small serving sizes.  In the real world, I expect people will likely consume more.

**I couldn’t find actual figures online for Just Juice with veggies, so I took the regular Just Juice and deducted 40% as per their claim.

**********

Clearly, Claire prides herself on being  media-savvy individual, and as a business model, you can’t fault it.  I’m sure shooting a 30 second advertisement offers a much better return on your time invested than doing consults all day, every day.  Between TV, radio, and glossy magazines (which just happens to also promote the products you are pumping on the idiot box), you have the ability to hit a much wider audience.  Hey, I did the same thing by opting to work in corporate health and running the Whole9 nutrition workshops.  Still haven’t got that TV deal though – NZ Beef & Lamb – call me!

Because Claire does have such a high media profile, you’d perhaps think that she’d be extra careful with regard to what she says.  Afterall, a) you would want to convey the most accurate information you could to a general public who is trusting in your guidance, and b) you never know who else might be watching and ready to pounce if you get it wrong.  So here is our TV dietitian at the start of last week addressing the recent Sydney Diet Heart Study published in the BMJ (I’m not going to rehash the details here as the likes of Tom Naughton has done an excellent job – here, here and here);

Butter vs. Margarine

Unfortunately, the TVNZ videos cannot be readily embedded, but hopefully you took the time to click-through for a watch.  But in case you couldn’t be bothered doing that (and just in case this video just happens to disappear in the same manner that the Sydney Diet Heart Study data did), here is what Claire said in response to her host’s question regarding butter vs. margarine and the BMJ research;

Well that piece of research wasn’t particularly life changing, really, and it wouldn’t be something that I would change what we advise on.  If you look at that piece of research, the margarine that they use in it was really really high in trans fats, which are equally bad if not worse for you than saturated fats.  So actually, that particular piece of research isn’t enough to change what we do….

…What it comes down to is saturated fat is heavily linked to heart disease and that’s our biggest killer in heart disease.  So 40% of people are dying from coronary heart disease.  And saturated fat is linked to that.  So one thing we can do is reduce butter, and for some people that just means using a lot less.  And maybe using a spread.  But if you don’t like the thought of using a spread, avocado, peanut butter, humus on bread…

So everyone just calm the f#%k down a bit, eh.  It turns out the researchers overlooked the fact that the spreads used in this study were high in trans fat.  A rookie mistake… carry on.

Only problem is, however, they DIDN’T overlook the trans fat issue – something Miss Turnbull would have known had she actually read the paper, thoroughly or otherwise.  Here is the section from the actual paper where the authors address the trans fat issue;

Another factor that could have been altered by the intervention is dietary trans fatty acids, which are known to raise total and low density lipoprotein cholesterol and have been associated with increased cardiovascular risk in observational studies.  This association was not widely appreciated during the SDHS, and the trans fatty acid content of participants’ diets was not recorded. Restriction of common margarines and shortenings (major sources of trans fatty acids) in the intervention group would be expected to substantially reduce consumption of trans fatty acids compared with the control group.

Conversely, some of this reduction in trans fatty acids in the intervention group may have been offset by small amounts of trans fatty acids in the safflower oil polyunsaturated margarine. Although the precise composition of this margarine was not specified, it was selected for the study because of its ability to lower blood cholesterol and its high PUFA to SFA ratio, two characteristics of margarines that contain comparatively low amounts of trans fatty acids.

Because dietary trans fatty acids are predominantly 18-carbon MUFA isomers, the recorded changes in MUFAs probably included small amounts of trans fatty acids in both groups.  Statistical adjustment for changes in MUFAs (an imperfect surrogate for trans fatty acids) in sensitivity analyses did not noticeably alter the observed relation between LA and increased risk of cardiovascular death in the intervention group (data not shown).

Collectively, these observations indicate that changes in trans fatty acid were unlikely to play a substantial role in the findings reported here. Nevertheless, the SDHS dataset does not contain sufficient information to rule out the possibility that changes in nutrients other than n-6 LA and SFAs could have contributed to, or reduced, the observed unfavorable effects of the LA intervention.

The Sydney Diet Heart Study data collection (and subsequent “misplacement”) took place in the 60′s.  This was a time before we had a good understanding of trans fats and as a consequence of not knowing of their effects, many of the margarines and shortenings produced were relatively high in trans fatty acids (due to the hydrogenation processes of the time).  Within the study, removing these foods from the intervention diets would have the effect of lowering the total trans fat intake.  The authors suggest that some may have been present in the safflower oil margarine used, but as trans fat has the effect of raising cholesterol levels and the safflower oil used in the intervention group lowered cholesterol, as expected, it was felt that trans fat exposure would be a) minimal, and b) both groups in the study would have equal exposure overall.  If both groups have similar levels of trans fat exposure, and it was the trans fat driving the negative outcomes in our vegetable oil group, as Miss Turnbull is trying to suggest in her breakfast TV slot, then you would expect to have seen no difference between groups.

Whilst the authors cannot rule out something other than polyunsaturated vegetable oils and saturated fats explaining the outcomes observed, it is unlikely to be due to trans fat.  Again, fairly obvious if you have read the study, no the effects of trans fat on blood cholesterol, and had looked at the data presented.  Misinformation – part one.

Misinformation – part two revolves around this statement made by Turnbull; “What it comes down to is saturated fat is heavily linked to heart disease.”  This is a bold statement to be making in light of the products that Turnbull puts her authoritative name to (cereals, cereal bars, fruit and vegetable juices).

Firstly, with have the 2010 meta-analysis on saturated fats and cardiovascular disease (this study has been criticised by those who perhaps find it a bit inconvenient and would really rather it just went away – this is a good dissection of those criticisms).  Let us remind ourselves of the findings from that review;

A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat.

From the same authors, this comment;

Furthermore, particularly given the differential effects of dietary saturated fats and carbohydrates on concentrations of larger and smaller LDL particles, respectively, dietary efforts to improve the increasing burden of CVD risk associated with atherogenic dyslipidemia should primarily emphasize the limitation of refined carbohydrate intakes and a reduction in excess adiposity.

I’ll leave it to you to decide whether the carbohydrates that Miss Turnbull is selling are refined or not…

And finally, from this Cochrane Collaboration review on the topic of fats and cardiovascular disease;

There are no clear health benefits of replacing saturated fats with starchy foods (reducing the total amount of fat we eat).

From Turnbull’s breakfast interview, she says this;

Overall what we are just wanting people to do in New Zealand is reduce the amount of unhealthy fats they are having…
…The thing is when it comes to fats, we’ve got to think about fats overall.  We’ve got spreads, butter and margarines, but we’ve also got fats in a lot of our food.  What it comes down to is saturated fat is heavily linked to heart disease…

It would seem that Turnbull is rolling out the tired old reduce total fats lines… “we’ve got to think about fats overall”.  And then there is the confusing statement, where she seems to acknowledge that we have fats in our spreads (in our industrial food ingredients), but is she really fingering the fats naturally present in our food?  More misinformation?

I did actually aim to give Turnbull the benefit of the doubt, sending her a couple of tweets regarding the information she presented in the interview on trans fats and what was actually stated in the paper.  She didn’t reply.  Though based on this tweet just before she went on air, I think she has other priorities for her twitter account than answering pesky nutrition questions;

I’ll finish up with two final quotes from the BMJ published Sydney Diet Heart Study, which should perhaps address our TV hosts’ (and Miss Turnbulls’) confusion around butter vs. margarine.

Reconciling results from the SDHS with the traditional diet-heart hypothesis

Increasing dietary n-6 LA [vegetable oils and spreads] in place of [saturated fat - SFA] lowers serum total cholesterol, primarily by reducing low density lipoprotein with little or no effect on high density lipoprotein.  The traditional diet-heart hypothesis predicts that these favorable, diet induced changes in blood lipids will diminish deposition of cholesterol in the arterial wall, slow progression of atherosclerosis, reduce clinical cardiovascular risk, and eventually improve survival.  As expected, increasing n-6 LA from safflower oil in the SDHS significantly reduced total cholesterol; however, these reductions were not associated with mortality outcomes.

Moreover, the increased risk of death in the intervention group presented fairly rapidly and persisted throughout the trial. These observations, combined with recent progress in the field of fatty acid metabolism, point to a mechanism of cardiovascular disease pathogenesis independent of our traditional understanding of cholesterol lowering.

Conclusions

In this cohort, substituting dietary n-6 LA in place of SFA increased the risks of death from all causes, coronary heart disease, and cardiovascular disease. An updated meta-analysis of LA intervention trials showed no evidence of cardiovascular benefit. These findings could have important implications for worldwide dietary advice to substitute n-6 LA, or PUFAs in general, for SFA.

Worldwide dietary advice implications indeed.  We have already seen signs of some bodies and associations scrambling to play this down.  But in the essence of thinking globally and acting locally, I’d just be happy if the likes of Miss Turnbull stopped spreading her brand of dietary misinformation.