Fats and Figures: Re-examining saturated fat and what’s really good for your heart

Fats and Figures cover 1400

A Facebook friend forwarded me an article a few weeks back and asked for my humble medical opinion.

The article was entitled, “World Renowned Heart Surgeon Speaks Out On What Really Causes Heart Disease”. It was written by a man who said he was a heart surgeon, and who claimed to be coming clean on the real reason why our world has an epidemic of obesity and heart disease despite the low fat advice of the medical profession.

It’s a highly controversial topic right now. For decades, the western world was under the impression that fat was tobaccos right hand man in a war on good health. Standard medical dogma was that high cholesterol was bad, and that saturated fat was its main source. Evil butter was replaced with angelic margarine. Fatty red meat was always served with a generous side portion of guilt. Low fat became high fashion.

Today, the pendulum of public opinion has swung back with such amazing ferocity, it’s become more like a wrecking ball. Fat has returned to the fold as friend instead of foe. The once mighty cholesterol lowering medications called statins have become seen as another example of pharmaceutical company profits-before-patients. Sugar has become the new villain, and along with it, the nebulous concept of “inflammation” as the key mechanism of heart disease and strokes, and nearly every other medical ailment.

What started off as a three-paragraph reply on Facebook has evolved into a short eBook, which you can download for free from Smashwords (https://www.smashwords.com/books/view/514719)

In today’s post, I want to look at six things that, over the years, have been touted as contributing to or preventing heart disease, and see what the evidence says. The results may be surprising!

1. Is saturated fat bad? Is polyunsaturated fat good?

According to a meta-analysis of observational studies on dietary fats by Chowdhury et al. (2014), relative risks for coronary disease were 1.02 (95% CI, 0.97 to 1.07) for saturated fats, 0.99 (CI, 0.89 to 1.09) for monounsaturated, 0.93 (CI, 0.84 to 1.02) for long-chain n-3 polyunsaturated, 1.01 (CI, 0.96 to 1.07) for n-6 polyunsaturated, and 1.16 (CI, 1.06 to 1.27) for trans fatty acids. The total number of patients in all of the trials was more than half a million. This is pretty convincing evidence that saturated fats aren’t as bad as first believed.

What does all this mean? In statistical terms, a relative risk is the incidence of disease in one group compared to the incidence of disease in another. The risk of the disease in the two groups is the same if the relative risk = 1. A relative risk of 7.0 means that the experiment group has seven times the risk of a control group. A relative risk of 0.5 would mean the experiment group has half the risk of the control group. The confidence interval is a range of numbers in which there is a 95% chance that the true relative risk is in the interval. A result is “statistically significant” when the confidence interval (CI) does not cross the number 1.

So going back to the study by Chowdhury et al. (2014), only 2% more patients in the group with the highest saturated fat consumption had heart disease compared to the lowest saturated fat consumption. The confidence interval crossed 1, so that result may have been due to chance alone. For trans fatty acid consumption, 16% more people had heart disease in the higher consumption group compared to the lower consumption group, which was probably a real effect and not due to chance (the confidence interval did not cross 1). Simply put, trans-fats are bad. Saturated fats probably aren’t.

The same meta-analysis by Chowdhury et al. (2014) also reviewed supplementation with PUFA’s on the overall risk of heart disease. They found that in 27 randomised controlled trials with more than 100,000 people, relative risks for coronary disease were 0.97 (CI, 0.69 to 1.36) for alpha-linolenic acid supplements, 0.94 (CI, 0.86 to 1.03) for long-chain n-3 polyunsaturated acid supplements, and 0.89 (CI, 0.71 to 1.12) for n-6 polyunsaturated fatty acid supplements. In this case, there was a trend in favour of supplementation with omega-3 and omega-6 supplements, but it was small, and may have been due to chance. This is confirmed by other reviews (Rizos, Ntzani, Bika, Kostapanos, & Elisaf, 2012; Schwingshackl & Hoffmann, 2014)

So it appears that it doesn’t matter what fat you consume, saturated or polyunsaturated, or whether you supplement with fish oils or eat lots of fish, your cardiovascular risk is much the same. The only thing that’s definitely clear is that you should avoid trans-fats.

2. Is sugar bad for you?

That depends.

When we think of sugar, we think of sucrose, a carbohydrate made up of one glucose and one fructose molecule. There are many carbohydrates, which are just various combinations of different numbers of glucose/fructose molecules, sucrose being one type.

Sugar consumption is thought to be the modern scourge, it’s consumption linked to everything from cancer to gallstones. It’s been recently become the villain of cardiovascular disease as well. It’s thought to cause insulin resistance, inflammation and an increase in the fats circulating in the blood stream. So, is it as bad as they say? The evidence is surprising.

First of all, sugar doesn’t make you fat. Rather, it’s the calories you consume that make you fat. Te Morenga, Mallard, and Mann (2013) conclude their meta-analysis of dietary sugar and body weight, “Among free living people involving ad libitum diets, intake of free sugars or sugar sweetened beverages is a determinant of body weight. The change in body fatness that occurs with modifying intakes seems to be mediated via changes in energy intakes, since isoenergetic exchange of sugars with other carbohydrates was not associated with weight change.”

The intake of sugar and glucose don’t cause an increase in inflammation or cholesterol in healthy people. In a study on effects of sugar consumption on the biomarkers of healthy people, Jameel, Phang, Wood, and Garg (2014) found that consumption of sucrose and glucose actually decreased cholesterol. Fructose increased cholesterol, though interestingly, the Total:HDL ratio (which is prognostic for heart disease) did not change significantly with the consumption of any form of sugar. They also found that fructose was associated with an increase in inflammation, but glucose and sucrose reduced inflammation.

On the other hand, a study by Isordia-Salas et al. (2014) showed a small but significant association between those with high blood glucose level and inflammation, though they also found an association between inflammation and BMI (the body-mass index), so it’s not clear what the causal factor is.

There seems to be a clearer association between blood glucose after meals in those who have abnormal glucose metabolism. In patients with pre-diabetes, higher levels of blood glucose two hours after eating were associated with increased risk of death from cardiovascular disease and all causes (Coutinho, Gerstein, Wang, & Yusuf, 1999; Decode Study Group, 2003; Lind et al., 2014).

To melt your brain a little more, just because high glucose levels are associated with higher mortality doesn’t mean the lower the glucose, the better. In the study by the Decode Study Group (2003), low blood glucose had a higher mortality than normal glucose levels, and a meta-analysis by Noto, Goto, Tsujimoto, and Noda (2013) showed that low carbohydrate diets have a 30% increase in all-cause mortality.

How do you pull all of these seemingly contradictory studies together? The bottom line appears to be, according to the evidence so far, that consumption of sugar does not cause inflammation or significantly increase the risk of heart disease in healthy people who are able to metabolise it properly.

In those people who have abnormal glucose metabolism, the higher the glucose is after a meal (a measure of how well the body processes glucose), then the higher the risk is of inflammation, heart disease, and all-cause mortality.

The distinction between who has normal glucose metabolism and who has dysfunctional glucose metabolism is probably related to genetics. A study by Sousa, Lopes, Hueb, Krieger, and Pereira (2011) showed that genetic information was able to predict 5-year incidence of major cardiovascular events and overall mortality in non-diabetic individuals, even after adjustment for the persons blood sugar. Those without diabetes but who had a high genetic risk had a similar incidence of cardiovascular events compared to diabetics. So if you have the genes, your body doesn’t process the glucose properly and your risk is increased, even if you aren’t bad enough to have a diagnosis of diabetes.

Thus it appears that sugar is not the bad guy that everyone makes it out to be. Excess sugar will make you fat, but so will excess everything-else. It probably won’t kill you unless you’re genetically pre-disposed to handle it poorly. And there’s the rub, because we don’t have the capacity to test for that clinically yet.

So the last word on sugar is that it’s a sometimes food. You may be lucky enough to handle large amounts of sugar, but the best advice at this time is don’t tempt fate by eating large quantities of it.

3. Is obesity bad for you?

Again, that depends.

It used to be thought that obesity posed a linear risk, that is, the fatter you were the higher your risk of heart attacks, cancer, diabetes, everything. Then in 2013, a meta-analysis by Flegal, Kit, Orpana, and Graubard (2013) showed that people who were overweight (but not obese) had better survival than those who were normal weight.

Later in 2013, Kramer, Zinman, and Retnakaran (2013) published a meta-analysis which showed that metabolically unhealthy people of normal BMI were at greater risk of cardiovascular disease than metabolically healthy obese people.

Last year a paper by Barry et al. (2014) showed that those who were unfit were twice as likely to die compared to people who were fit, irrespective of their BMI.

So obesity doesn’t seem to be the problem after all, rather it’s a persons ability to handle blood sugar, cholesterol and blood pressure that’s the problem. It seems that more people with obesity have these metabolic problems, but correlation does not equal causation. There’s probably a undetermined factor that links obesity and metabolic dysfunction.

I’m not suggesting that we should all get fatter. Obesity has problems of its own, unrelated to metabolic issues, that make it problematic. We should still be careful about our weight. The take-home message is that skinny does not necessarily mean healthy and that focusing on what the scales are saying may be distracting us from the real problem.

4. Is meat bad for you? Should we be vegetarians?

In a word, no.

In the two available meta-analyses of the studies on red meat consumption (Larsson & Orsini, 2014), and red meat vs white meat vs all meat (Abete, Romaguera, Vieira, Lopez de Munain, & Norat, 2014), there was a statistical but moderate increase in death and heart disease from processed meats.

There was a trend towards a higher death rate in those who ate the most red meat, but the trend wasn’t statistically significant (i.e.: may have been related to chance). There was no trend associated with white meat consumption. So it appears that as long as it’s not processed meat, red meat isn’t as bad as people first thought.

Meat might not be particularly bad, but are vegetarian diets better? Again, probably not. The meta-analysis by Huang et al. (2012) shows that there’s a positive trend for vegetarian diets, though again, that might be attributable to chance as the results are not statistically significant.

The take-away message? Even though the trends may be related to chance, the trend is favourable for vegetables and not as favourable for red meat. So eat more veggies, eat less red meat, but don’t let some sanctimonious vegan convince you that meat is noxious and vile.

5. Is alcohol good for you?

A different meme recently came around my Facebook feed, entitled, “Is Drinking Wine Better Than Going To The Gym? According To Scientists, Yes!” For a while there, I had fantasies about giving my membership card back to the gym and heading down to the local bottle shop for my daily workout instead.

Disappointingly, it turns out that red wine isn’t better than exercise according to the research that I uncovered. However, my research did suggest that the daily exercise of wine drinking is still beneficial, and not just red wine, but alcohol of any form. Ronksley, Brien, Turner, Mukamal, and Ghali (2011) showed about two standard drinks of alcohol daily conferred a 25% reduction in deaths from heart disease (relative risk 0.75 (0.68 to 0.81)), and a small but statistically strong reduction in death from all causes of 13% (relative risk 0.87 (0.83 to 0.92)). The risk reduction of coronary heart disease from alcohol was also confirmed in a more recent study by Roerecke and Rehm (2014), who showed that death from heart disease was reduced by 36% for those who consistently consumed less than three standard drinks a day (relative risk 0.64 (0.53 to 0.71)).

The effect applies to consistent daily consumption, not to drinking in a cluster pattern (binging or weekend-drinking only, for example). And there’s a gender difference, women having the maximum beneficial effect at about one drink a day, and two drinks a day in men.

6. Is exercise good for you?

In a word, yes!

I’ve never seen a study that showed exercise was harmful. Exercise improves overall metabolism, decreases cardiovascular disease, improves mood and memory and increases your lifespan, amongst many other things. If exercise came in pill form, it would be labelled a wonder-drug.

As discussed earlier, fit people have a better rate of survival compared to unfit people, whether they’re obese or not (Barry et al., 2014). And the key to fitness is exercise. In a large meta-analysis by Samitz, Egger, and Zwahlen (2011), 80 studies involving more than 1.3 million subjects in total were analysed, showing that the highest levels of exercise had an all cause mortality reduction of 35% (relative risk 0.65 (0.6 to 0.71)).

There’s always debate about what form of exercise is best. Are you better to do weights, do interval training, or run for hours? Honestly, it probably doesn’t matter that much in the end. What is important is that you work hard enough to elevate your heart rate and break a sweat. If you aren’t very fit, it won’t take much exercise to do that. If you are very fit, it probably will. But for the average person, you don’t have to jump straight into a boot camp style program and work so hard that you’re puking everywhere, and so sore afterwards that you can’t move for a week. Common sense prevails!


Abete, I., Romaguera, D., Vieira, A. R., Lopez de Munain, A., & Norat, T. (2014). Association between total, processed, red and white meat consumption and all-cause, CVD and IHD mortality: a meta-analysis of cohort studies. Br J Nutr, 112(5), 762-775. doi: 10.1017/S000711451400124X

Barry, V. W., Baruth, M., Beets, M. W., Durstine, J. L., Liu, J., & Blair, S. N. (2014). Fitness vs. fatness on all-cause mortality: a meta-analysis. Prog Cardiovasc Dis, 56(4), 382-390. doi: 10.1016/j.pcad.2013.09.002

Chowdhury, R., Warnakula, S., Kunutsor, S., Crowe, F., Ward, H. A., Johnson, L., . . . Di Angelantonio, E. (2014). Association of dietary, circulating, and supplement fatty acids with coronary risk: a systematic review and meta-analysis. Ann Intern Med, 160(6), 398-406. doi: 10.7326/M13-1788

Coutinho, M., Gerstein, H. C., Wang, Y., & Yusuf, S. (1999). The relationship between glucose and incident cardiovascular events. A metaregression analysis of published data from 20 studies of 95,783 individuals followed for 12.4 years. Diabetes Care, 22(2), 233-240.

Decode Study Group, E. D. E. G. (2003). Is the current definition for diabetes relevant to mortality risk from all causes and cardiovascular and noncardiovascular diseases? Diabetes Care, 26(3), 688-696.

Flegal, K. M., Kit, B. K., Orpana, H., & Graubard, B. I. (2013). Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis. JAMA, 309(1), 71-82. doi: 10.1001/jama.2012.113905

Huang, T., Yang, B., Zheng, J., Li, G., Wahlqvist, M. L., & Li, D. (2012). Cardiovascular disease mortality and cancer incidence in vegetarians: a meta-analysis and systematic review. Ann Nutr Metab, 60(4), 233-240. doi: 10.1159/000337301

Isordia-Salas, I., Galvan-Plata, M. E., Leanos-Miranda, A., Aguilar-Sosa, E., Anaya-Gomez, F., Majluf-Cruz, A., & Santiago-German, D. (2014). Proinflammatory and prothrombotic state in subjects with different glucose tolerance status before cardiovascular disease. J Diabetes Res, 2014, 631902. doi: 10.1155/2014/631902

Jameel, F., Phang, M., Wood, L. G., & Garg, M. L. (2014). Acute effects of feeding fructose, glucose and sucrose on blood lipid levels and systemic inflammation. Lipids Health Dis, 13(1), 195. doi: 10.1186/1476-511X-13-195

Kramer, C. K., Zinman, B., & Retnakaran, R. (2013). Are metabolically healthy overweight and obesity benign conditions?: A systematic review and meta-analysis. Ann Intern Med, 159(11), 758-769. doi: 10.7326/0003-4819-159-11-201312030-00008

Larsson, S. C., & Orsini, N. (2014). Red meat and processed meat consumption and all-cause mortality: a meta-analysis. Am J Epidemiol, 179(3), 282-289. doi: 10.1093/aje/kwt261

Lind, M., Tuomilehto, J., Uusitupa, M., Nerman, O., Eriksson, J., Ilanne-Parikka, P., . . . Lindstrom, J. (2014). The association between HbA1c, fasting glucose, 1-hour glucose and 2-hour glucose during an oral glucose tolerance test and cardiovascular disease in individuals with elevated risk for diabetes. PLoS One, 9(10), e109506. doi: 10.1371/journal.pone.0109506

Noto, H., Goto, A., Tsujimoto, T., & Noda, M. (2013). Low-carbohydrate diets and all-cause mortality: a systematic review and meta-analysis of observational studies. PLoS One, 8(1), e55030. doi: 10.1371/journal.pone.0055030

Rizos, E. C., Ntzani, E. E., Bika, E., Kostapanos, M. S., & Elisaf, M. S. (2012). Association between omega-3 fatty acid supplementation and risk of major cardiovascular disease events: a systematic review and meta-analysis. JAMA, 308(10), 1024-1033. doi: 10.1001/2012.jama.11374

Roerecke, M., & Rehm, J. (2014). Alcohol consumption, drinking patterns, and ischemic heart disease: a narrative review of meta-analyses and a systematic review and meta-analysis of the impact of heavy drinking occasions on risk for moderate drinkers. BMC Med, 12(1), 182. doi: 10.1186/s12916-014-0182-6

Ronksley, P. E., Brien, S. E., Turner, B. J., Mukamal, K. J., & Ghali, W. A. (2011). Association of alcohol consumption with selected cardiovascular disease outcomes: a systematic review and meta-analysis. BMJ, 342, d671. doi: 10.1136/bmj.d671

Samitz, G., Egger, M., & Zwahlen, M. (2011). Domains of physical activity and all-cause mortality: systematic review and dose-response meta-analysis of cohort studies. Int J Epidemiol, 40(5), 1382-1400. doi: 10.1093/ije/dyr112

Schwingshackl, L., & Hoffmann, G. (2014). Dietary fatty acids in the secondary prevention of coronary heart disease: a systematic review, meta-analysis and meta-regression. BMJ Open, 4(4), e004487. doi: 10.1136/bmjopen-2013-004487

Sousa, A. G., Lopes, N. H., Hueb, W. A., Krieger, J. E., & Pereira, A. C. (2011). Genetic variants of diabetes risk and incident cardiovascular events in chronic coronary artery disease. PLoS One, 6(1), e16341. doi: 10.1371/journal.pone.0016341

Te Morenga, L., Mallard, S., & Mann, J. (2013). Dietary sugars and body weight: systematic review and meta-analyses of randomised controlled trials and cohort studies. BMJ, 346, e7492. doi: 10.1136/bmj.e7492

Dr Caroline Leaf and dualism revisited

Screen Shot 2015-01-18 at 9.05.13 pm

Are we a body with a mind, or a mind with a body?

This may sound like a chicken-and-egg type of conundrum, but it’s a deep philosophical question. The concept of the separation of the mind from the body is known as dualism, and has been debated for centuries because the answer to that question then guides a lot of other philosophies and theories.

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. She believes that the body and brain are separate from the mind, which significantly influences her teaching. Take, for example, her social media meme-of-the-day today. She posted that, “The brain does not change itself… our MIND changes the brain”. If one assumes that the mind is separate from our brain, then its plausible that the mind influences the brain.

Except that it doesn’t. Our mind is a product of our brain, not a separate entity. Neurological damage from injuries or tumours, electrical stimulation of the brain in the lab, the effect of illicit drugs on the brain like LSD or marijuana, and everyday examples like the changes to our thinking under the influence of caffeine or alcohol, all prove that changes to the structure and function of the brain change thought patterns. It isn’t the other way around. Every brain changes itself too – the brain of an embryo or foetus undergoes massive changes but foetuses don’t have streams of conscious thought. Dr Leaf’s meme is scientifically misguided.

Perhaps what is more worrying is Dr Leaf’s use of scripture to try and justify her view that the mind and the brain are separate. To introduce her meme, Dr Leaf wrote, “Read Luke 16:19-31 to see that the mind is separate from the brain – this is God’s divine design.”

There are a number of scriptures that theologians use to discuss the biblical basis for the separation of the body and soul, but Luke 16:19-31 isn’t one of them. That passage is the parable of Lazarus and the rich man.

It says:

‘There was a rich man who was dressed in purple and fine linen and lived in luxury every day. At his gate was laid a beggar named Lazarus, covered with sores and longing to eat what fell from the rich man’s table. Even the dogs came and licked his sores.
‘The time came when the beggar died and the angels carried him to Abraham’s side. The rich man also died and was buried. In Hades, where he was in torment, he looked up and saw Abraham far away, with Lazarus by his side. So he called to him, “Father Abraham, have pity on me and send Lazarus to dip the tip of his finger in water and cool my tongue, because I am in agony in this fire.”
‘But Abraham replied, “Son, remember that in your lifetime you received your good things, while Lazarus received bad things, but now he is comforted here and you are in agony. And besides all this, between us and you a great chasm has been set in place, so that those who want to go from here to you cannot, nor can anyone cross over from there to us.”
‘He answered, “Then I beg you, father, send Lazarus to my family, for I have five brothers. Let him warn them, so that they will not also come to this place of torment.”
‘Abraham replied, “They have Moses and the Prophets; let them listen to them.”
‘“No, father Abraham,” he said, “but if someone from the dead goes to them, they will repent.”
‘He said to him, “If they do not listen to Moses and the Prophets, they will not be convinced even if someone rises from the dead.”’ (Luke 16:19-31, NIV)

I’m not sure exactly where the convincing proof of the separation of our mind and our body is found in this passage. This is a description of the afterlife, and in this parable, the rich man was very specific about memories (“I have five brothers …”) as well as physical sensations (“I am in agony in this fire”) and even parts of the body (Lazarus’s finger, his tongue). Jesus isn’t telling a story of how the mind is separate to the body, but of a different dimension in which the body and the mind are still together. This passage isn’t proof for the concept of dualism, but against it.

Dualism also has a number of fatal scientific and philosophical flaws, in particular that dualism is conceptually fuzzy, experimentally irrefutable, considers only the adult mind, and violates physics, in particular the law of conservation of energy.

So Dr Leaf bases her teaching on a scientifically and philosophically untenable concept and then attempts to use a scripture which refutes dualism in her attempt to support it. That’s audacious, but then to claim that it’s God’s divine design is, at best, a little brazen.

Dualism may be one of her fundamental philosophies, but I think Dr Leaf should review the basis for it, and possibly reconsider her reliance on it.

For a more in-depth discussion on Dr Leaf and dualism, please see my essay: Dr Caroline Leaf, Dualism, and the Triune Being Hypothesis

Going green – why envy is an adaptive process

The Bible says, in Job 5:2, “For wrath kills a foolish man, And envy slays a simple one.”

A German proverb goes, “Envy eats nothing, but its own heart.”

Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, posted today on her social media feeds, “Jealousy and envy creates damage in the brain … but … celebrating others protects the brain!”

Yes, sometimes envy isn’t good for us. Emotions guide our thought process, and like all emotions that are out of balance, too much envy can cloud our better rational judgement and bias our perception of the world. Thankfully, envy doesn’t literally eat out our hearts or literally cause brain damage.

If anything, envy when experienced in a balanced way can actually improve our brain functioning. According to real cognitive neuroscientists, envy and regret are emotions that help us because they both fulfil the role of effectively evaluating our past actions, which improves our choices in the future. As Coricelli and Rustichini noted, “envy and regret, as well as their positive counterparts, share the common nature that is hypothesized in the functional role explanation: they are affective responses to the counterfactual evaluation of what we could have gotten had we made a different choice. Envy has, like regret, a functional explanation in adaptive learning.” [1]

When it comes to the human psyche, there is no black or white, good vs evil distinction between different feelings or emotions. B-grade life coaches and slick pseudoscience salespeople dumb down our emotions into a false dichotomy because it helps sell their message (and their books). Every emotion can be either helpful or unhelpful depending on their context in each individual.

As Skinner and Zimmer-Gembeck wrote, “Emotion is integral to all phases of the coping process, from vigilance, detection, and appraisals of threat to action readiness and coordinating responses during stressful encounters. However, adaptive coping does not rely exclusively on positive emotions nor on constant dampening of emotional reactions. In fact, emotions like anger have important adaptive functions, such as readying a person to sweep away an obstacle, as well communicating these intentions to others. Adaptive coping profits from flexible access to a range of genuine emotions as well as the ongoing cooperation of emotions with other components of the action system.” [2]

If you find your thoughts and feelings tinged by the greenish hue of envy, don’t worry, it’s not necessarily a bad thing. Your heart isn’t going to consume itself and you won’t sustain any brain damage. Use envy or regret as tools of learning, tools to help you evaluate your choices so that you make a better choice next time. Having balanced emotions is the key to learning and growing, coping with whatever obstacles life throws at us.


  1. Coricelli, G. and Rustichini, A., Counterfactual thinking and emotions: regret and envy learning. Philos Trans R Soc Lond B Biol Sci, 2010. 365(1538): 241-7 doi: 10.1098/rstb.2009.0159
  2. Skinner, E.A. and Zimmer-Gembeck, M.J., The development of coping. Annu Rev Psychol, 2007. 58: 119-44 doi: 10.1146/annurev.psych.58.110405.085705

Dr Caroline Leaf and the law of great power

Screen Shot 2014-12-05 at 12.37.55 am

Tonight as I was flicking through Facebook one last time, a post caught my eye. It read,

“The thought you are thinking right now is impacting every single one of the 75-100 trillion cells in your brain and body at quantum speeds”

Dr Leafs social media gem gave me an eerie sense of deja vu. It was only the end of October when she posted the same factoid on social media. Today’s version has been tweaked slightly, although in all fairness, I can’t describe it as an upgrade.

Dr Caroline Leaf is a communication pathologist and self-titled cognitive neuroscientist. On the 23rd of October 2014, she posted this on her social media stream, “Every thought you think impacts every one of the 75-100 trillion cells in your body at quantum speeds!”

On comparing the pair, Dr Leaf has added “brain” into the number of cells under the influence, and then massaged the opening slightly. I already had significant concern about the scientific validity of the previous meme in October. That hasn’t changed. Rather than improving the accuracy of her meme, Dr Leaf’s changes have left it missing the mark.

The fundamental fallacy that thoughts are the main controlling influence on our brain is still there. Thought is simply a conscious projection of one part of the overall function of our brain. Our brains function perfectly well without thought. Thought, on the other hand, doesn’t exist without the brain. Our brain cells influence our thoughts, not the other way around.

The myth of “quantum speeds” is still there. Our neurones interact with each other via electrochemical mechanisms. Like all other macroscopic objects, our brains follow the laws of classical physics. It’s not that quantum physics doesn’t apply to our brains, because quantum mechanics applies to all particles, but if you think you can explain macroscopic behaviour using quantum physics, then you should also try and explain Schrodingers Cat (see also chapter 13 of my book [1] for a longer discussion on quantum physics). Dr Leaf is particularly brave to make such bold statements about quantum physics when even quantum physicists find it mysterious.

What made me slightly embarrassed for Dr Leaf is the new part of her statement. In my blog on Dr Leaf’s previous attempt at this meme, I pointed out that Dr Leaf’s estimate of the number of cells in our body was more than three times that of the estimate of scientists at the Smithsonian (http://www.smithsonianmag.com/smart-news/there-are-372-trillion-cells-in-your-body-4941473/?no-ist). The fact that Dr Leaf so badly estimated, when all she needed to do was a one line Google search, suggested that she just made the number up. Failing to cite her source eroded at her credibility as a scientist.

Today, Dr Leaf still claims that there are 75-100 trillion cells in the brain and the body. The Smithsonian still hasn’t changed its estimate. Dr Leaf still hasn’t cited her source, and has ignored a world-renowned scientific institution. Perhaps Dr Leaf believes she knows more than the scientists at the Smithsonian? Perhaps she has a better reference? We’ll never know unless she cites it.

Taken as a whole, her meme is no closer to the truth than it was six weeks ago. Some may ask if it really matters. “Who cares if we have 37.2 trillion cells or 100 trillion cells or even 100 billion trillion”. “So what if our thoughts influence us or not.” If this was just a matter of a pedantic argument between some scientists over a coffee one morning,then I’d agree, it wouldn’t be so important. But Dr Leaf claims to be an expert, and more than 100,000 people read her memes on Facebook and many more on Twitter, Instagram, and the various other forms of social media she is connected to. Nearly every one of those people take Dr Leaf at her word. Ultimately the issue is trust.

If Dr Leaf can misreport such a simple, easily sourced fact, and not just once but twice now, then what does that mean for her other factoids and memes that she regularly posts on social media? If Dr Leaf incorrectly says that every thought we think impacts every cell in our body, then hundreds of thousands of people are wasting their mental and physical energy on trying to control their thoughts when it makes no real difference, and if anything might make their mental health worse [2, 3].

This is more than just a pedantic discussion over a trivial fact.  These memes matter to people, and can potentially influence the health and wellbeing of many thousands of lives.

Peter Parker, quoting Voltaire, said, “With great power comes great responsibility.”  Just because Spiderman said it doesn’t diminish the profundity of that statement.  This law of great power applies to Dr Leaf as much as it does to Spiderman.  I hope and pray that she gives this law of great power the consideration it deserves.


  1. Pitt, C.E., Hold That Thought: Reappraising the work of Dr Caroline Leaf, 2014 Pitt Medical Trust, Brisbane, Australia, URL http://www.smashwords.com/books/view/466848
  2. Garland, E.L., et al., Thought suppression, impaired regulation of urges, and Addiction-Stroop predict affect-modulated cue-reactivity among alcohol dependent adults. Biol Psychol, 2012. 89(1): 87-93 doi: 10.1016/j.biopsycho.2011.09.010
  3. Kavanagh, D.J., et al., Tests of the elaborated intrusion theory of craving and desire: Features of alcohol craving during treatment for an alcohol disorder. Br J Clin Psychol, 2009. 48(Pt 3): 241-54 doi: 10.1348/014466508X387071

Dr Caroline Leaf and the cart before the horse, take two

Screen Shot 2014-12-01 at 8.23.44 pm

In between her sightseeing in the UK and ballet concerts in the Ukraine, Dr Leaf, communication pathologist and self-titled cognitive neuroscientist, took the time to post some more memorable memes.

Today, Dr Leaf posted, “A chaotic mind filled with thoughts of anxiety, worry, etc. sends out the wrong signal right down to the level of our DNA.”

Hmmm, that one looked familiar … actually, Dr Leaf posted the exact same phrase on the 5th of October this year.  I’m all for recycling, but of renewable resources, not tired ideas.

This meme has been soundly rebuffed before, and the idea that the mind controls our DNA has been thoroughly dismantled.  Reposting it won’t make it any truer.

This meme is better off being put into the trash than the recycling bin.

(For more information on the rebuttal of the mind over matter meme, see also “Hold that thought: Reappraising the work of Dr Caroline Leaf“, “Dr Caroline Leaf: Putting thought in the right place” Part 1 and Part 2, “Dr Caroline Leaf and the matter of mind over genes“, “Dr Caroline Leaf, Dualism, and the Triune Being Hypothesis”, “Dr Caroline Leaf and the Myth of the Blameless Brain” and “Dr Caroline Leaf and the Myth of Mind Domination” just to name a few references).

Dr Caroline Leaf and the organic foods fallacy

Screen Shot 2014-11-28 at 1.13.59 am

Organic foods. They are amazingly popular. More than a million Australians buy organic foods regularly, and several million more buy it occasionally. The retail value of the organic market is estimated to be more than $1 billion annually. The assumption made by most people is that because it’s so popular, organic foods must be good for you, or at least have something going for them to make them worth all the hype.

Of course, just because something’s immensely popular and has a billion-dollar turnover doesn’t necessarily mean it’s beneficial (One Direction is a case-in-point).

In fact, despite organic foods being touted by their supporters as healthier, safer, and better for the environment than normal foods, actual scientific evidence fails to show any significant difference. I wrote about this earlier in the year (see: Borderline Narcissism and Organic Food). Since then, another large prospective trial deflated organic food’s bubble, with a British study showing no change in the incidence of cancer in women who always ate organic foods versus those who never ate organic foods [1].

The dearth of benefit from organic foods wouldn’t be so bad if they were just another guy in the line-up, something neutral and inert. Unfortunately, not only can organic produce be contaminated if farmed incorrectly [2, 3], but they come at an extraordinary premium, sometimes costing four times more than their conventional counterparts (Borderline Narcissism and Organic Food).

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. A couple of months ago, she let slip her intention to publish a book in 2015 about food. Who knows what she’ll actually say, but if today’s social media meme is anything to go by, it will likely follow the same pattern of her other teachings.

Today, she wrote, “Research shows that dark organic CHOCOLATE lowers blood pressure, improves circulation, increase HDL (“good”) cholesterol, reduce the risk of heart attack and stroke, and increases insulin … and … recent research has even suggest it may prevent weight gain!”

As I discussed recently, Dr Leaf does herself a disservice by not citing her sources. It’s very brave to write in a public forum that dark chocolate reduces the heart attack and stroke, since this could be interpreted as medical advice, which she is not qualified to give. As for the actual effects of dark chocolate, there is not a lot of quality evidence on dark chocolate on its own. A 2011 meta-analysis of general chocolate consumption on cardiovascular risk did indeed show a relative risk reduction of 37% [4]. But before you prescribe yourself two dark chocolate Lindt balls twice a day, consider that a relative risk reduction of 37% isn’t a big effect. Plus, the recommended 50 grams of 85% organic dark chocolate to attain the small benefit for your cardiovascular health contains just over 300 calories/1280 kJ (the average can of Coke contains 146 calories/ 600 kJ), and is 30% saturated fat (http://caloriecount.about.com/calories-green-blacks-organic-dark-chocolate-i110689). So any health benefit that may be associated with the poly-phenol content is likely nullified by the high saturated fat and calorie count.

What concerns me about Dr Leaf’s future foray into dietetics is that little word sitting quietly in her opening sentence: “organic”. Dr Leaf is an organic convert. But rather than act like a scientist that she claims to be, she preaches from her biases, ignoring the evidence that organic food is all hype and no substance, encouraging Christians everywhere to pay excessive amounts of money for something that’s of absolutely no benefit. Dr Leaf is welcome to eat whatever she chooses, but encouraging organic eating without clear benefit is more hindrance than help for most of her followers.


  1. Bradbury, K.E., et al., Organic food consumption and the incidence of cancer in a large prospective study of women in the United Kingdom. Br J Cancer, 2014. 110(9): 2321-6 doi: 10.1038/bjc.2014.148
  2. Mukherjee, A., et al., Association of farm management practices with risk of Escherichia coli contamination in pre-harvest produce grown in Minnesota and Wisconsin. Int J Food Microbiol, 2007. 120(3): 296-302 doi: 10.1016/j.ijfoodmicro.2007.09.007
  3. Sample, I., E coli outbreak: German organic farm officially identified. The Guardian, London, UK, 11 June 2011 http://www.theguardian.com/world/2011/jun/10/e-coli-bean-sprouts-blamed
  4. Buitrago-Lopez, A., et al., Chocolate consumption and cardiometabolic disorders: systematic review and meta-analysis. BMJ, 2011. 343: d4488 doi: 10.1136/bmj.d4488

Dr Caroline Leaf and the tongues trivia tall tales

Screen Shot 2014-11-12 at 9.29.17 pm

In every day life, if someone started talking in strings of indecipherable, chaotic syllables, you’d be giving them quite a lot of space, concerned about how much methamphetamine they’d been using.

In the average charismatic church, it’s just another service (the speaking in tongues, not the meth).

I’ve grown up in Pentecostal churches, and was baptised in the Holy Spirit when I was a child, so I forget how freaky it is for those who’ve never seen a whole church start talking or singing in tongues. For the uninitiated, the Bible talks about speaking in other tongues, which is a “New Testament phenomena where a person speaks in a language that is unknown to him. This language is either the language of angels or other earthly languages (1 Cor. 13:1). It occurred in Acts 2 at Pentecost and also in the Corinthian church as is described in 1 Corinthians 14. This New Testament gift was given by the Holy Spirit to the Christian church and is for the purpose of the edification of the Body of Christ as well as for glorifying the Lord.” (http://carm.org/speaking-in-tongues)

In scientific terms, speaking in tongues is referred to as “Glossolalia”, from the Greek, ‘glosso-‘ ~ ‘the tongue’ and ‘-lalia’ ~ ‘to speak, to chat’. Scientists who initially studied it in the 60’s and 70’s drew the conclusion that glossolalia was related to psychopathology (that people who spoke in tongues were crazy) [1, 2], and in later decades, it was thought to be caused by a form of temporal lobe epilepsy [3].

Earlier today, Dr Caroline Leaf, a communication pathologist and self-titled cognitive neuroscientist, declared that, “When we speak in tongues, research shows that the areas involved in discernment in the brain increase in activity, which means we increase in wisdom.”

I was fascinated to find this research for myself. Dr Leaf never references her social media memes, so I started looking through the medical literature on the subject from respected databases like PubMed, and search engines like Google Scholar.

Despite a thorough search, I was only able to find one article that studied the pattern of brain activity during speaking in tongues. The article, “The measurement of regional cerebral blood flow during glossolalia: A preliminary SPECT study” [4] took five healthy women, psychiatrically stable, long term members of their churches, who had all spoken in tongues for many years. They scanned their brain activity after a period of singing to gospel songs in English and compared it to their brain activity after the same amount of time praying in tongues (while listening to the same music as before).

What they found was that the brain was more active in the left superior parietal lobe, while there was a decrease in brain activity in the prefrontal cortices, left caudate nucleus and left temporal pole. There was a trend for an increase in the activity of the right amygdala, but this may have just been chance.

So are any of those brain regions responsible for discernment as Dr Leaf suggested?

Well, that all depends on how you define “discernment”. “Discernment” is not really a common neurobiological term. The standard term in the literature is “judgement”. The brain regions that are associated with evaluation and judgement are the amygdala and ventral portions of the striatum as well as the ventromedial prefrontal cortex (vmPFC), orbitofrontal cortex (OFC), the insula, the dorsal anterior cingulate cortex (dACC), and the periaqueductal gray (PAG) [5].

Are there any parts of the brain that match in the two lists? Only one – the ventromedial prefrontal cortex, or vmPFC for short. The prefrontal cortex is important in reasoning and decision-making, especially if there is uncertainty or novelty, while the vmPFC in particular is involved in the use of goal-relevant information in guiding responses, e.g., assigning value to choice options [6].

According to Dr Leaf, “When we speak in tongues, research shows that the areas involved in discernment in the brain increase in activity”. But that’s certainly not what the research paper said. The actual research is entirely the opposite.

Again, there are really only two reasonable explanations as to why the research contradicts Dr Leaf; either there is another piece of research which supports Dr Leaf’s assertion, or Dr Leaf is simply wrong.

At the risk of repeating myself, Dr Leaf needs to quote her sources when she is writing her little social media memes. Her meme may be perfectly justified by robust scientific evidence, but if she isn’t willing to share her sources, we’ll never know, and the only conclusion remaining is that Dr Leaf can’t interpret simple research.

So as it stands, there really isn’t any evidence that speaking in tongues makes you more discerning. By trying to claim otherwise, Dr Leaf further undermines her own reputation and credibility as an expert.


  1. Hine, V.H., Pentecostal glossolalia: towards a functional reinterpretation. Journal for the Scientific Study of Religion, 1969. 8: 212-26
  2. Brende, J.O. and Rinsley, D.B., Borderline disorder, altered states of consciousness, and glossolalia. J Am Acad Psychoanal, 1979. 7(2): 165-88 http://www.ncbi.nlm.nih.gov/pubmed/370074
  3. Persinger, M.A., Striking EEG profiles from single episodes of glossolalia and transcendental meditation. Perceptual and Motor Skills, 1984. 58: 127-33
  4. Newberg, A.B., et al., The measurement of regional cerebral blood flow during glossolalia: a preliminary SPECT study. Psychiatry Res, 2006. 148(1): 67-71 doi: 10.1016/j.pscychresns.2006.07.001
  5. Doré, B.P., et al., Social cognitive neuroscience: A review of core systems, in APA Handbook of Personality and Social Psychology, Mikulincer, M., et al., (Eds). 2014, American Psychological Association: Washington, DC. p. 693-720.
  6. Nicolle, A. and Goel, V., What is the role of ventromedial prefrontal cortex in emotional influences on reason?, in Emotion and Reasoning, Blanchette, I., (Ed). 2013, Psychology Press.

STOP THE PRESSES! Dr Leaf releases a new meme based on my correction, still doesn’t acknowledge source. (13 November 2014)

Screen Shot 2014-11-13 at 8.08.23 am


So, I can’t find fault on what Dr Leaf said here.  It fits with the paper I quoted from Newberg et al (2006).  Still, it begs the question of why Dr Leaf couldn’t have said this in the first place, and why she still isn’t willing to share her citations?

It also raises the other obvious question, why is it important to know what our brain does in glossolalia?  It’s only a study of 5 patients, and I’m sure that not all episodes of speaking in tongues is associated with decreased intentionality.  The research, being so small, isn’t a true reflection of the practice of speaking in tongues.  Lets hope that the future will bring more funding to better study this central tenet to the charismatic faith.