2013 is definitely going to be the year you honor your New Year’s resolution to diet and exercise more. Definitely! But before you spend money on work-out devices or weight-loss supplements, check out these seven old ads from the Popular Science archive, and remember that if something seems too good to be true, it’s probably going to embarrass you later. (Or it might be a scary amphetamine; see slide 6.)

Bonus: An ad for weight-gain tablets that promises to help “thousands of thin, tired, nervous people” pack on the pounds. Because everyone knows that “no skinny man has an ounce of sex appeal!”

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The Waist Belt System: August 1981

“I’ve worn it to work, playing softball, tennis, exercising, and just about anything I want to do. My weight dropped 16 pounds!” According to the gushing “real people” in this 1981 ad, the rubber Waist Belt System was an easy, quick way to ditch inches from your midsection. An unnamed scientist claimed the “invigorating” and “distinctive” (yes, I would say so) Waist Belt holds in body heat, “causing excess fluids in the body’s tissues to literally ‘melt away.’ ” See the full ad here.

The Slimming Down Plan: June 1969

“A girl can’t stomach a guy with a pot belly,” sneers this mean ad from 1969. The $17.96 Slimming Down Plan, complete with Slim Gard girdle, Slimmer Shake protein drink, and Aerobic/Circuit exercise routine, claimed it could help you lose a pound a day. Unless that was a really intense exercise program, I can’t imagine that a new shirt and some protein shakes did much to slim down Mr. Bulgey over there (who, for the record, looks perfectly fit and handsome to me.) See the full ad here.

The Space Age Slenderizer: February 1981

Do you have extra body bits you want to get rid of? “Second Skin will actually take off bloaty pounds and ugly inches from your entire body.” The Space Age Slenderizer was a sweaty, shiny exercise bag that promised to help you “lose up to 5 pounds in just 15 minutes!” Wait… are those the same models from the Waist Belt ad? See the full ad here.

Thera-Slim-100: May 1978

This “no-drug,” “hi-amino” weight-loss product seems pretty dubious. Works like “powdered heat”? Plus, it has some ghastly fine print: “Aside from–ABSOLUTE STARVATION–there is no surer, faster, more effective way to slash away pounds.” Yikes. See the full ad here.

The Protam Plan: June 1948

With Protam, you can lose weight “economically, simply, pleasantly.” Good for ladies, too! The product in this 1948 ad appears to be some sort of vitamin–much less sinister than the pill in this next ad… See the full ad here.

The Total Contentment Pill: April 1977

This 1977 ad doesn’t say exactly what’s in the Total Contentment appetite-killing pill, but my money’s on a whole lotta amphetamine. “So effective it helps shut off your appetite for hours at a time… instead of yielding to hunger… you simply reach for a pill instead.” At the bottom of the ad is a very sick, very sad box: “VITAL NOTICE: You must promise to eat. Yes, even though the Total Contentment Pill has the ability to turn off your appetite just like you turn off a light switch, YOU CANNOT GO ON FOR LONG PERIODS EATING NOTHING… even though you have no appetite. Sure, you’d lose weight like crazy… but the doctor says it’s unhealthy.” See the full ad here.

Ironized Yeast Tablets: March 1939

And finally, let’s not forget that thin wasn’t always the way to be. “Thousands of skinny, rundown people who never could gain before have quickly put on pounds of solid, naturally attractive flesh, with these remarkable scientifically tested little Ironized Yeast tablets.” Yum! See the full ad here.