It wasn't until 1957, when Americans ate as much margarine as they did butter - 8.5 pounds per year - that margarine, which was marketed as both a healthier and cheaper butter alternative, opened the spread in its favour.
Fat had become a food faux pas, and the margarine industry used its widening wallet to tout margarine's supposed health appeal.
"The massive advertising of health claims for margarine transformed a generally disreputable product of inferior quality and flavour into a great commercial success," William G. Rothstein wrote in his book Public Health and the Risk Factor.
Even Eleanor Roosevelt came to margarine's aid. "That's what I've spread on my toast," she said in a 1959 commercial for Good Luck margarine.
The thing about advertising is that it often works. For some 50 years thereafter, it was butter that was left to congeal in the fridge. In 1976, at the peak of America's love affair with margarine, per capita consumption towered to just under 12 pounds per year, or nearly three times that of butter, according to the USDA.
Today, however, amid a complete reversal in both consumer preferences and nutritional science - recent studies have challenged the notion that consuming saturated fats is tied to greater risks of heart disease - margarine's marketing efforts have lost their appeal and the narratives have reversed themselves.
Growing concerns over processed foods and a simultaneous, and ferocious, revival of the American appetite for natural fats has turned the tables - and this time, seemingly, for good. Even one of the world's largest margarine makers has conceded as much.
After announcing the return of butter back in March, Mark Bittman wrote in defence of real food and real fats just last week. "Eat real food and your fat intake will probably be fine," he said. If America's taste in fatty spreads is any indication, the country seems to have already caught on. Butter consumption is up more than 21 per cent since its lowest reading in 1997, while margarine consumption is down 70 per cent since its peak in the mid-1970s.
Put another way, the average American hasn't eaten this much butter since 1972, or - and perhaps more incredibly - this little margarine since 1942.
- Washington Post