"Someone at some point in government has done their sums: Man A lives on the govt approved diet, he works all his life and drops dead at 60 of a heart attack (or spends the last 10 years off work due to diabetes related illnesses). Max cost to govt: 10 years healthcare & benefits. Man B lives on low carb diet, works until he's 65 and then claims pension until he dies at 100. Cost to govt: 35 years of pension payments, plus care home fees. Govt answer: Let them eat cake. (Make sure cake is v. cheap)"