For That Extra Endurance

In 1939, Knox Gelatine sponsored a dubious scientific study that proclaimed gelatin to be an effective aid in improving muscular endurance. Over the course of several weeks, ten research participants—six men and four women—were asked to use an exercise machine until fatigue set in, with or without a daily drink of fruit juice mixed with gelatin. The study concluded that, due to the amino acids in gelatin, men were able to increase their efforts on the machine by a staggering 37 to 240 percent. (Women seemed be unaffected.)

The study immediately drew fire for its flawed design, lack of a proper control group, and insufficient sample size. footnote footnote By the year's end, the American Medical Association had dropped Knox from its list of "accepted foods," criticizing the company for promoting these unsubstantiated claims. footnote

Knox seemed unbothered. In 1940, they released a "Fight Fatigue! Drink Knox Gelatin" year-long ad campaign in Life magazine—as well as in Woman's Day, despite the fact that their own study indicated gelatin could not alleviate fatigue in women. Knox was vague on this point, referring to mysterious "recent scientific experiments and test cases," with "proof on file with Good Housekeeping." footnote (Not dissimilar to "Source: trust me bro.")

Consumer Reports was particularly incensed by Knox's deception, noting that there had not in fact been any new corresponding studies published in medical journals. They sneered: "The validity of these tests was so clear that the Knox Co. felt impelled to file the data in that austere repository of contemporary scientific proceedings—Good Housekeeping." footnote

It doesn't appear that Knox suffered any significant repercussions for this practice, and by the following year, they were newly promoting their gelatin as a preventative for the common cold, despite lack of scientific proof. footnote