President Trump wants to impose a 20% tariff on Mexican imports. How many Americans will that kill? Let’s play with some numbers.
The Bureau of Labor Statistics reports (I’m looking at Table 13 in that link) that in 2012, approximately 125 million U.S. households spent an average of $731 on fruits and vegetables. That’s about $91 billion altogether.
I learn from this page that the US imports about $9 billion worth of fresh fruits and vegetables each year from Mexico. That is, then, about 10% of our fruit and vegetable consumption.
I learn from various research reports around the web that the price elasticity of demand for fruits and vegetables is somewhere in the vicinity of .50. (Some say higher, some say lower). This means that a 20% tariff — as the president has just called for — will reduce imports by about 10%.
So the Trump tariff should reduce total U.S. fruit and vegetable consumption by about 10% of 10% — that is, about 1%.
(This is, deliberately, a considerable underestimate, since it entirely ignores the fact that the tariff will also lead to increases in the price of American vegetables, leading to further reduced consumption.)
Now here I learn that low fruit and vegetable consumption is associated with a higher risk of degenerative diseases, including cancer, cardiovascular disease, cataracts and brain dysfunction. “More than 200 studies in the epidemiological literature show, with great consistency, an association between low consumption of fruits and vegetables and high cancer incidence.” Many of the mechanisms for this are well understood. For example, folic acid deficiency leads to chromosome breaks and then to cancer. Your health risks do not drop off continuously with your vegetable consumption; instead there are sudden changes — you’re either above or below the level where chromosome breaks occur. (There are similar issues with at least eight other micronutrients — in addition to folic acid — that we get from fruits and vegetables.) About 10% of the U.S. population is below that critical level. Most of those have very low incomes. (The World Health Organization estimates that worldwide, about 5 million people a year die from inadequate fruit and vegetable consumption, and most of those are very poor.) For a first (very rough) approximation, let’s assume that those with folic acid deficiencies are in fact the poorest 10%. You can see here that these are people with individual incomes below about $10,000.