Currently low food prices don’t have any negative consequences in game. If food prices fall too low, they do not affect the following:
Impacting farmer income.
Farmer opinion and membership.
Food waste (increase in CO2 emissions)
Farmers protests (such as throwing or burying harvested crops, disease outbreak situation should affect this too) due to the expense of harvesting and/or transport exceeding the selling price of the harvest (or demand falling too low in the case of Disease Outbreak)This could be a future situation along with these relations.
I don’t know, cutting subsidies somewhat, increasing restrictions on antibiotics, etc. Currently, there is no incentive to increase food prices to a sustainable level, only to send them rock bottom. Of course if the subsidies are themselves sending food prices rock bottom, instead of market forces, I’m not sure how farmers would feel. There may not be a linear link here, but I hope some exploration of this can yield a more realistic outcome, as with rare earth metal prices.
The only impact i know of is obesity. In Democracy 3 or Democracy Africa (i don’t remember which one), i one had lowered the food price too much but that lead to obesity. Then as you said, increasing restrictions on antibiotics, increasing taxes on junkfood, or increasing the food agency criterias can make the price go up again if you want. As for farmers, i think it’s good as it is since the diminishing of food price is a direct result of the different subsidies you put in place, which means that the government gives farmer money so that farmers produce food at low cost. For example the organic farming subsidy in real life gives farmers money so that they could do organic farming and sell their product at a competitive price. In summary the government is paying for the difference between the real price and the low price paid by people.
Well it seems to me that for you there is a treshold that should not be exceeded in food prices, and once you exceed it there should be some negative effects. I don’t know what makes you think this (and i am curious to know), but i don’t see any problem with low food prices, especially if it is paired with very high taxes on junk food. I mean even if the food is free (except junk food), as long as the government is able to pay the bills, the farmers are happy because they have the money et people are happy because the can eat without paying (they pay taxes but you understand what i want to say). The problems that i can think of are obesity but with junk food tax that should be okay, and the other is if there is enough food for everybody (in democracy there is no concept of imports and exports and i think it should be added, so we assume all the food is produced in-house). Apart from these two problems i don’t see any relating to low food prices.
This should probably also be affected by subsidies. If food prices are low, a quick fix is to subsidies the crop in question and appease the farmers. This can result in a spiral though, where new farmers plant subsidized crops in order to earn reliable income, which increases the number of people reliant on subsidies and thus makes them harder to remove. This is the current situation with corn in the US, where production far outpaces demand, but the crop remains profitable due to billions in payouts.
Well, what about when prices fell so low during the height of the pandemic, that farmers were burying food, because supply so far outstripped demand, that it was cheaper to bury the food than transport it, even harvesting the food caused losses to farmers.