3 Ways to Spot Their Lies About Healthy Recipes

Briefly: If I had to name the one word, that is most often used to label something as what it is not, my vote would go to "healthy". Whether it's the issue of sugar vs. honey, of butter vs. oil or of calories vs. nutrients, science and evidence are clearly not playing the lead role in the culinary theater of the world wide web. Judging by its popularity, that's a missed opportunity.

I recently gave a talk on the lies and deceptions the food industry uses in labeling and marketing their products. A German corporate health insurance had asked me to give that presentation to their clients. Naturally, a large percentage of the audience were women. Judging from the lively and entertaining discussion, which followed my presentation, almost all women prefer home cooked food for their families to take-out or eat-out. The most often cited reason was that home cooked food is the healthier choice. I'm not convinced that they get it. Not if they get their food information from where they professed to search for it: the internet.

I know this, because in preparation for my talk I followed my wife on one of her culinary search trips through the web.

The number of recipe sites is staggering. So is the degree of misinformation disseminated by them. Most of it in the form of labeling something as healthy when it clearly isn't. Let's look at three commonly encountered mis-perceptions on randomly chosen recipe sites. I won't give you the links, because to single them out would be unfair. What I found there is so ubiquitous, that you will encounter it virtually everywhere once you start surfing the culinary side of the web.

Honey vs. Sugar

A self-proclaimed holistic health counselor shares her recipe for a "Healthier Flourless Chocolate Cake". Which immediately begs the question: healthier compared to what? The answer comes in brackets directly behind the title, where it says "refined-sugar free". Reducing sugar in our daily diet is certainly a big step towards better health. But you won't get there by replacing sugar with honey. The difference between sugar and honey is simple: Sugar is 100% sugar, honey is 80% sugar. Admitted, that's a little oversimplified. Honey does have ingredients which sugar doesn't. But these are not an issue when it comes to reducing calories or the metabolic impact of sugar. Whether you sprinkle granulated sugar into the dough or fold honey into it, what your metabolism has to deal with is their common denominator, the breakdown molecule, which ends up in your blood - glucose. Of the recipe's remaining 4 ingredients - butter, eggs, cocoa powder and baking chocolate - the butter is evidence that our holistic health counselor has missed out on another common diet mis-perception:

Butter vs. Oil

On another website we find the "Best Ever Healthier Chocolate Brownies". Honey isn't an issue for this lady. Her claim to healthiness is based on the conviction that other recipes use "... butter rather than olive oil", and that "olive oil contains healthier fats". This butter vs. oil issue is not as straight forward as the glucose theme. So let's look at it in greater detail.

The fats for human nutrition come either from animal or plant sources, and you can think of them in 3 major categories: saturated fats, and mono- and poly-unsaturated fats. We don't need to go into the molecular details of the fats - or fatty acids (FA), as they are more correctly called. Suffice it to say, that the "unsaturated" part of the descriptor refers to one (mono) or more (poly) carbon atoms of the fatty acid molecule having less than the maximally possible number of hydrogen atoms linked to them. Depending on the position of the first "unsaturated" atom in the chain of carbon atoms, the poly-unsaturated fats are called omega-3 or omega-6 poly-unsaturated fatty acids (PUFA). There is one more thing you should be aware of: the human body can manufacture most of the fatty acids which it needs for its metabolism and maintenance. But there are two, which we need to supply through our food intake. These two are alpha linolenic acid (ALA), an omega-3 FA, and linoleic acid (LA), an omega-6 FA. Our organism uses them to produce other fatty acid variants which are essential for our health.

Armed with this knowledge we can now ask ourselves an obvious question: What's the health issue with fats? You have probably heard that a high fat diet promotes high levels of cholesterol in your blood (partly true) and that high cholesterol is the cause of heart disease (not true). You have also heard that saturated fats, such as butter, are bad for you and that replacing it with olive oil is good for your health.

Now let's hear the facts as we know them today: Dietary trials in which saturated fat, such as butter, was replaced by PUFA lead to a reduction in risks for cardiovascular disease [1]. However, when those PUFAs were mainly of the omega-6 version, there was no reduction, or even a slight increase in risk for heart disease. Looks like replacing saturated fats with oils isn't going to do you any good if you don't chose the oils for their content of omega-3 FAs.

These observations match nicely with what we know from evolutionary biology. Comparing the fat intake between our hunter/gatherer ancestors and us, we notice that the ratio of omega-6 to omega-3 fatty acids has undergone a dramatic change. While that ratio stood at 1:1 or even lower throughout most of human evolution, our modern western diet has upped that ratio to a whopping 16:1 [2], and even greater than that, depending on where you live. When I now tell you that the downstream products of your omega-6 FA intake are pro-inflammatory whereas the products of ALA have the opposite effects, you might begin to see the picture. With heart disease and stroke being the late-stage consequences of chronic inflammation of the arteries, as I highlighted in my earlier post "Your Shortcut To Longevity", the type of fat appears to have an effect on your arterial health. And therefore on your risk of heart disease.

How large this effect really is, remains unclear. In a recently updated review of randomized clinical trials the Cochrane Collaboration came to the conclusion that reducing the content of saturated fat in favor of unsaturated fats had some effect on cardiovascular disease events in men only (not in women) and only if such dietary habit change lasted at least 2 years [3]. There was no detectable effect on the risk of dying from cardiovascular disease. Importantly, it was unclear whether the reduction in disease events was due to poly- or mono-unsaturated fatty acids.

There is another issue I have with that song and dance about olive oil. Its omega-6:omega-3 ratio is around 13, which doesn't exactly make it heart healthy. In comparison, the much maligned coconut oil has no omega-3 FAs only omega-6. But it delivers only a third of the omega-6 FA of olive oil. In contrast, sunflower oil also has no omega-3 component but delivers almost 6 times as much omega-6 as olive oil. The only really stand-up guy in the vegetable oil department is flaxseed oil: its omega6:omega3 ratio is 0.3, which makes it as good as any of the fish oils, which are considered healthy. But don't get too excited about flaxseed oil taking over your kitchen anytime soon. It can't hide it's similarity with fish oil. I tried it. It's OK in a salad, and so are the seeds. Heat up the oil, though, and you think you are frying a cod liver. That taste doesn't go too well with a chocolate cake, or many other dishes.

So, what's the point? Of course, you can read the evidence as you like, but I wouldn't call a brownie or chocolate cake healthier when the only merit to this claim is its oil content. To me, the excess in calories is what by far outweighs the relative merits of the carriers of theses calories. Which brings me to the third issue:

Calorie Density vs. Nutrient Density

When I added up the calories for the brownie and the cake, the calorie-to-weight ratio was in excess of 4. That is, every 100 grams of these buggers deliver more than 400 calories. This nutrient density of 4 is way in excess of what man was exposed to through most of evolution. Think about it: fruits come with a ratio of 0.6, on average, vegetables with a ratio of 0.3 and game meat, the only meat available to our cave dwelling ancestors, delivers on average 200 calories for every 100 gram. We can reasonably assume that our ancestors had to survive on an overall calorie-to-weight ratio of less than 2. Add to this the fact that they expended far more calories than we do today. Just to maintain calorie balance our ancestors had to eat a much larger quantity of food than we do today. And that food, while low in calories, was packed with nutrients. So, their nutrient:calorie ratio was certainly far more favorable than ours is today.

There are many more issues which plague much of the web's culinary universe. By right, the word healthy shouldn't be anywhere near most of its places. Particularly when those places are all about eating and nothing about exercise. You can eat as healthy as you like, if you fail to exercise at the right frequency, intensity and volume, then pay-back day is almost inevitable.

How your arteries benefit from exercise, and how you can make that exercise exactly right for you with the least possible effort, that will be an issue of my next post. Until then, don't get hooked too much on the culinary web. I worked up a hell of an appetite during my recipe surfing exercise with my wife. Didn't do any good to my waist line and probably not to my arteries. But, what the hell, we need to enjoy sometimes, too.    

1.           Kuipers, R.S., et al., Saturated fat, carbohydrates and cardiovascular disease. Netherlands Journal of Medicine, 2011. 69(9): p. 372-8.

2.           Simopoulos, A.P., The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cardiovascular Disease and Other Chronic Diseases. Experimental Biology and Medicine, 2008. 233(6): p. 674-688.

3.           Hooper, L., et al., Reduced or modified dietary fat for preventing cardiovascular disease. Cochrane Database Syst Rev, 2012. 5: p. CD002137.

Kuipers RS, de Graaf DJ, Luxwolda MF, Muskiet MH, Dijck-Brouwer DA, & Muskiet FA (2011). Saturated fat, carbohydrates and cardiovascular disease. The Netherlands journal of medicine, 69 (9), 372-8 PMID: 21978979

Simopoulos, A. (2008). The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cardiovascular Disease and Other Chronic Diseases Experimental Biology and Medicine, 233 (6), 674-688 DOI: 10.3181/0711-MR-311

Hooper L, Summerbell CD, Thompson R, Sills D, Roberts FG, Moore HJ, & Davey Smith G (2012). Reduced or modified dietary fat for preventing cardiovascular disease. Cochrane database of systematic reviews (Online), 5 PMID: 22592684

Your shortcut to longevity.

If you don't die from an accident, a serious infection or a cancer, you'll live as long as your arteries let you. And how long they let you is all in your hands. I know this sounds over-simplified, but it's biomedical knowledge in a nutshell. Lets look at what happens in and to your arteries and what that means for keeping them in mint condition. 

 You may have thought about your arteries as elastic tubes, which transport blood to where its oxygen and nutrient load is needed. But there is more to it. For example, there is this very thin lining which separates the muscular elastic wall of the arteries from the blood stream. This lining is called the endothelium, and it is where the difference is made between lifestyle and death style.

The endothelium is a one-cell-thin layer which has often been likened to the teflon coating on your non-stick pots and pans. The only true part of that analogy is the non-stick part. It prevents cholesterol and fat from docking on to endothelial cells and gradually growing into atherosclerotic plaques. When they rupture, blood clots form and those clots might cause a heart attack or stroke. I say "might" because not all plaque ruptures turn into such dramatic events, but we will get to this later.

Many people think that a chronic overdose of cholesterol or fat, or simply aging, are the causes of atherosclerosis. That was the working hypothesis of scientists 50 years ago. But it doesn't jibe with the observation that half of all patients with confirmed atherosclerotic lesions, have cholesterol values within the normal range [1]. That's because plaques grow WITH cholesterol, any amount of cholesterol, but they start growing ON inflammation. Chronic inflammation, to be precise. And chronic inflammation grows on your physical activity habits. Or rather the lack thereof.

Inflammation in itself is nothing bad. It's a process by which cells rid themselves of invaders. Only when inflammation becomes chronic do we have a problem. To avoid chronicity, endothelial cells have a mechanical switch. Or, as we call it in biomedicine: a mechanoreceptor. Those receptors respond to pulsatile blood flow. That is, if those receptors are being hit often, long and strong enough by blood waves gushing through the artery, they trigger an anti-inflammatory cascade of hormonal reactions. If we don't keep hitting those receptors, the cascade turns pro-inflammatory and the career of the atherosclerotic plaque begins. The extremely complex biochemical happenings do not concern us here. What concerns us is that this pounding of the endothelial cell receptors doesn't come from sitting around, or from playing golf or from walking through the park. It only comes from vigorous physical activity.  Which explains the growing evidence for the relative benefits of more intensive vs. less intensive physical activity.

One example is a recent study by researchers who had followed close to 20000 adults aged 20-90 for almost 20 years, monitoring their cycling habits and their health [2]. The study took place in the Danish city of Copenhagen where 5 Million people own 4 Million bicycles. Male study participants who reported habitual cycling at the highest of three intensity levels lived on average 5.3 years longer than their peers in the lowest intensity group, independent of the duration of cycling. Of course, this was a prospective cohort study, which only allows us to talk association but not causality. But its findings match nicely with the expectations we have from our knowledge about the anti-inflammatory effects of higher-intensity exercise. Specifically, that high-intensity exercise inhibits the oxidative processes which precede and coincide with inflammation in the endothelial cells [3]. These effects were either absent or negligible in exercise of moderate intensity. By the way, this second study had been performed in women. I point that out, just so that you don't think what applies to male Danes may not apply to women. 

Now, what's the good news in all this for those devotees of the minimalistic physical activity lifestyle, otherwise known as couch potatoes?

The good news is, that you don't have to spend hours in endurance exercise. In my lab we have seen significant improvements in fitness and health with thrice weekly 20-minutes high-intensity interval training (HIT). In our HIT routine our participants spent those 20 minutes with 4 consecutive intervals, in each of which they ran or cycled for 4 minutes at moderate intensity, followed by a 1-minute all-out sprint, with no break between intervals. A recent review confirmed the benefits of HIT [4], which accumulate with a significantly smaller time commitment to exercise, than what is required for conventional endurance exercise.

There is more good news. Remember that I mentioned that the rupture of an atherosclerotic plaque "may" cause a heart attack or stroke. That's because we know a couple of interesting and encouraging things about such plaques. First, plaques may be of a "vulnerable" or of a "stable" type. The stable ones don't rupture easily but the vulnerable ones do. Secondly, not all those plaque ruptures end in a heart attack or stroke. Most ruptures actually don't. And we can't predict exactly which ones will cause problems, and when. So there is a large element of chance in all this. Third, plaques can change their status from vulnerable to stable or vice versa within weeks or months.

The good news in all this is that it is in your hands, or rather in your exercise, whether your existing plaques become more stable, and whether you decrease or increase the chance of a heart attack or stroke. All it takes is the intensity of your exercise.

The bad news, those insights take away your excuse of lack of time. Think about it, what are 60 minutes a week for HIT, when the average German spends 4 hours PER DAY watching TV, and the average American tops that with another 2 hours a day.

So, when you want to know whether your physical activity habits qualify as a lifestyle or a death style, keep the simple reasoning in mind: exercise determines the health of your arteries, and the health of your arteries determines your longevity. And the shortcut to the latter goes via HIT.   

1.           Braunwald, E., Shattuck lecture--cardiovascular medicine at the turn of the millennium: triumphs, concerns, and opportunities.N Engl J Med, 1997. 337(19): p. 1360-9.

2.           Schnohr, P., et al., Intensity versus duration of cycling, impact on all-cause and coronary heart disease mortality: the Copenhagen City Heart Study. European Journal of Cardiovascular Prevention & Rehabilitation, 2011.

3.           Ciolac, E.G., et al., Effects of high-intensity aerobic interval training vs. moderate exercise on hemodynamic, metabolic and neuro-humoral abnormalities of young normotensive women at high familial risk for hypertension. Hypertension Research, 2010. 33(8): p. 836-843.

4.           Kent, W., The effects of sprint interval training on aerobic fitness in untrained individuals: a systematic review.British Journal of Sports Medicine, 2011. 45(15): p. A8.

Schnohr, P., Marott, J., Jensen, J., & Jensen, G. (2011). Intensity versus duration of cycling, impact on all-cause and coronary heart disease mortality: the Copenhagen City Heart Study European Journal of Cardiovascular Prevention & Rehabilitation, 19 (1), 73-80 DOI: 10.1177/1741826710393196