(1) For substitution effects, we looked at (a) substitution with respect to home foods (i.e. the fear is we make outside food less sweet, so people just make their own food at home and add lots of sugar or sweet sauces); and (b) Substitution with respect to salty food (which leads to hypertension etc).
(a) For substitution with respect to home foods: We found that this is likely not a material risk insofar as:
(i) Our taste for sweetness is adaptive, and reducing sugar intake makes high sugar food taste too sweet even as low sugar food tastes sweeter than before. This is in line with what is the case for salt, where the phenomena of desensitization also exists.
(ii) A mass media campaign will be looking to address this precise issue, and to the extent we expect behavioural change with respect to highly processed food, we have equal reason to expect change with respect to seasoning of home foods.
(b) For substitution with respect to salty food: The evidence with respect on the cross-price elasticity is mixed, for as Dodds et al note: “A US study found that nutrient taxes targeting sugar and fat have a similar impact on salt consumption as a dedicated salt tax, likely because many foods, especially junk foods, that are high in sugar are also high in salt.”; in contrast “A New Zealand experimental study … [finds] that salt taxation led to a 4.3% increase in the proportion of fruit and vegetables purchased, but also a 3.2% increase in total sugars as a percentage of total energy purchases.” Given this, we took that it would be reasonable to assume no net benefit or cost with respect to sugar consumption.
(c) For alcohol, we didn’t look at this explicitly—though per Teng et al, the evidence is mixed, and from my own sense from going through the literature is that there is a small but significant substitution effective, and this will have to be modelled more explicitly going forward.
(2) On industry—we do look at the role of industry in general, and consider it an important factor that made us downgrade our estimate of the chances of advocacy success.
Hi Ramiro,
Those are good questions!
(1) For substitution effects, we looked at (a) substitution with respect to home foods (i.e. the fear is we make outside food less sweet, so people just make their own food at home and add lots of sugar or sweet sauces); and (b) Substitution with respect to salty food (which leads to hypertension etc).
(a) For substitution with respect to home foods: We found that this is likely not a material risk insofar as:
(i) Our taste for sweetness is adaptive, and reducing sugar intake makes high sugar food taste too sweet even as low sugar food tastes sweeter than before. This is in line with what is the case for salt, where the phenomena of desensitization also exists.
(ii) A mass media campaign will be looking to address this precise issue, and to the extent we expect behavioural change with respect to highly processed food, we have equal reason to expect change with respect to seasoning of home foods.
(b) For substitution with respect to salty food: The evidence with respect on the cross-price elasticity is mixed, for as Dodds et al note: “A US study found that nutrient taxes targeting sugar and fat have a similar impact on salt consumption as a dedicated salt tax, likely because many foods, especially junk foods, that are high in sugar are also high in salt.”; in contrast “A New Zealand experimental study … [finds] that salt taxation led to a 4.3% increase in the proportion of fruit and vegetables purchased, but also a 3.2% increase in total sugars as a percentage of total energy purchases.” Given this, we took that it would be reasonable to assume no net benefit or cost with respect to sugar consumption.
(c) For alcohol, we didn’t look at this explicitly—though per Teng et al, the evidence is mixed, and from my own sense from going through the literature is that there is a small but significant substitution effective, and this will have to be modelled more explicitly going forward.
(2) On industry—we do look at the role of industry in general, and consider it an important factor that made us downgrade our estimate of the chances of advocacy success.