08 August 2017

Future elevated CO2: another reason to cure our "Anemia Amnesia "

I have written about our collective "Anemia Amnesia" before.  Anaemia is the nutrition condition that has high prevalence worldwide and is decreasing at a snails pace (see any Global Nutrition Report). It has serious consequences for cognitive ability, work capability, and greater rate of maternal and child mortality. 

So it is doubly alarming to read a paper by Smith, Golden and Myers in the latest GeoHealth which concludes that this situation is likely to worsen due to elevated levels of carbon dioxide as we move towards 2050.   

The paper combines FAO food balance sheet data at the national level, uses the Global Dietary Database to get some granularity on iron availability for 1-5 year olds and women of reproductive age, and then combines this with the 2014 estimates from Myers et al. on the impacts of elevated CO2 on zinc and iron concentrations of key crops.  This latest paper answers the "so what?" from the 2014 paper: what impact will these lower concentrations have on potential iron deficiency numbers?

The paper labels countries as high, medium and low risk of increased anaemia due to elevated CO2. Countries classified as high risk have levels of anaemia >20% AND modelled loss in dietary iron that would be most severe (over 3.8%).

For sure, the estimates of impacts on risk of iron deficiency are built on a series of big assumptions (including on the relevance of elevated CO2 estimates beyond the country the data are from, food group aggregation, the distribution of bioavailability and the changing nature of diets), but they seem reasonable to me.  

So what do they find?  The figure below shows the key result. 

You can see that South Asia, South-Eastern Africa and North Africa are the most at risk of a potential rise in iron deficiency prevalences. They contain 1.4 billion at risk children 1-5 and women of reproductive ages (not to mention older children and men who also suffer from anemia). Across all countries, the estimated percentages of lost dietary iron under elevated CO2 ranged from modest to more severe: 1.5–5.5%. Estimates for all countries are available in the open access paper. 

Why are the populations in these countries most at risk?  First the populations of these countries have high levels of anaemia and second they consume large amounts of the foods that are most at risk of iron concentration loss due to elevated CO2 (rice, wheat flour, maize and fresh vegetables). 

What are the policy implications of this work?  The authors state: 

"The potential risk of increased iron deficiency adds greater incentive for mitigating anthropogenic CO2 emissions and highlights the need to address anticipated health impacts via improved health delivery systems, dietary behavioral changes, or agricultural innovation. Because these are effects on content rather than yield, it is unlikely that consumers will perceive this health threat and adapt to it without education."

I agree with this.  The policy pay off to this work is more on the adaptation than the mitigation side. In other words while this result adds to the case for reducing CO2 emissions, more importantly, I think, it is a real wake up call to the nutrition community.  Act now on micronutrient content of the diet because it is not going to get much easier in the future.  The two systems that need to become more attuned to this problem are health systems (to address diseases that reduce iron absorption) and food systems (to make iron rich foods more available and affordable).  

But arguably the most important sentence in the authors' conclusion is the the last one.  Unlike food quantity the effects on the nutrition content of foods (whether from elevated CO2, seed varieties selected, storage, transport or processing lose) are hard to detect.  So we need more mechanisms for signalling nutrition content of foods in ways that inform the consumer: whether certification, labelling or behaviour change campaigns.  

Lack of food is relatively easy to observe, but a lack of nutrients is not.  Governments and businesses in food systems need to focus more on nutrient content.  They will be rewarded with healthier--and wealthier--citizens and consumers.

04 August 2017

Gastrophysics: the new science of eating

I was trained as an economist and although we work with "preferences" we tend to think of consumption behaviour being driven by prices, income, gender based rules and convenience, with preferences relatively fixed.

So it is refreshing to read Charles Spence's book: Gastrophysics: The new science of eating because it focuses on pretty much everything else that drives preferences and choices.

Spence is a Professor at Oxford University's Crossmodal Research Laboratory.  Crossmodal because his team examines how different senses connect with each other (e.g. when someone puts on red lighting and suddenly the red wine in your black glass tastes sweeter). He is an experimental psychologist and he has defined the term gastrophysics as "the factors that affect our multi sensory experience while tasting food and drink".  Watch an interview with him here.


For instance:

* Sound: when a potato crisp makes a louder crunch, it enhances perceptions of freshness
* Sight: crab flavoured ice cream that is pink will not work in the Western world because the colour pink is associated with sweetness
* Name: the real name for the popular Chilean sea bass is Patagonian tooth fish (not too many people will order that)
* Expectations: "Pasta salad" does not sound as healthy as "salad with pasta"
* Atmosphere (literally): 27% of drinks bought on airplanes are tomato juice because its flavour is strong enough to survive the sensory dimming effects of high altitude and loud noise
* Labelling: using phoney farms in the labelling of foods (e.g. Rosedene and Nightingale) makes consumers feel the food is healthier
* Shapes: customers were convinced that a famous brand of chocolate had become more sweet when the corners of the blocks became more rounded.  The formula had stayed the same but people associated smooth corners with sweetness.
* Silence is golden: labelling a product lower in sugar or fat --when it it really has been lowered--is a risky business for companies because it might make consumers taste it differently
* People: we all live in our different taste worlds, some are "super tasters" with 16 times as many papillae on the front of their tongues as the rest of us.
* Smell: a rose oil soaked sugar cube in a glass of sparkling water or champagne, transports you to a rose garden
* Shapes: beer labels tend to have sharp angular logos connoting bitterness
* Colour: using blue plates in hospitals increases the consumption of food because bland hospital food tends to look even blander against white plates
* Orientation: the rotation of the plate matters (we tend to prefer food in pyramids)
* Motion: yolks, oozing chocolate, juice flowing into a glass (all imply freshness)
* Look: the more beautiful a source of food tends to look, the less aromatic it tends to be (ugly fruit lovers take note)
* Sound: the sounds that coffee machines make affects the taste of the coffee made
* Touch: "the first taste is with the hands" -- what do the eating implements feel like? (Textured spoons anyone?)
* Touch: are hamburgers more popular because we eat them with our hands and not with sharp, cold metallic objects being inserted into our mouths?
* Sound: accompanying music must not be too loud, and it can stimulate preferences for certain kinds of food (accordions for French music etc)
* Social: the tapas-isation of eating--sharing can enhance flavour

So what has all this to do with making the world more well nourished?   For me, these are the takeaways (no pun intended):

1. I don't hear the words flavour, desirability, cravings or delicious at many nutrition meetings or events.  We need to talk about these attributes and dimensions if we want to create a greater demand for healthy foods

2. Many of the examples in the book are from Europe and North America, but as Spence notes this is just a reflection of where the research has been conducted to date--the approach is likely to be universally useful, although of course it needs adapting to context.

3. Changing some of the drivers of consumption are not necessarily expensive.  Colours, shapes, names.  We just need to clue into the psychology of eating.

4. Businesses are better than the public sector at this type of gastrophysics research (I suspect) and when they invest in it, little will ever make it into the public domain.  We need to find ways of working with them to get more of it geared towards healthy eating and into a shareable space.

Just as nutrition is not only about food, food is not only about nutrients.  It is about eating.  Getting people to eat differently is not easy.  This new science promises to give us a few more tools and ideas to do so.  Let's be open to it and not just dismiss it as fluff (pink coloured, of course).