Thanks to author Mireille Guiliano, there is a widely-accepted belief that French women don't get fat. Our Gallic counterparts, she explained in her bestselling book, can eat pains au chocolat for breakfast and still fit into their Isabel Marant skinnies, and enjoy crusty white bread at lunch without falling into a carb-induced food coma at their desk an hour later.
The myth that French women don't get fat became even further entrenched following the release of Guiliano's book, but it looks like it may finally be debunked by another French author, who has taken an entirely different tack. You're Not Born Fat is the real-life story of Gabrielle Deydier, France's first openly-fat woman - they hide the rest of them in the attic.
Deydier has two degrees, but because she weighs 23st, she is discriminated against in the workplace and verbally abused on the street. A colleague once told her, matter-of-factly, that he didn't work with fat people. A gynaecologist once remarked: "There's so much blubber here, I can't see."
We have long been told that French women don't get fat because they have a guilt-free relationship with food. Only now Deydier's book delves deeper into the country's cultural mores, and exposes the quiet tyranny of the portion control police and the ostracising effects of what she calls "grossophobia".
The French are proud of their global reputation as a culture that can enjoy the finer things in life - red wine, white bread, blue cheese - without succumbing to porcine self-abandon. They are not, how you say, le pig.
They don't, however, like to look behind the façade, and talk about the 50,000 gastric-band operations that take place each year, the bewildering array of cellulite creams on the pharmacie shelves or the ever-present fear of being pronounced 'à la limite' - the phrase they use to describe the verge of being overweight.
It must be confusing to live in a country where high-fat foods are celebrated, yet fat people are reviled, and it makes you wonder if French people feel under pressure to be, well, French.
Take the idea that French women savour croissants for breakfasts. Sure, they indulge every now and again, but they are also fastidiously aware of their waistlines. In truth, many of them skip breakfast, save for black coffee. Intermittent fasting is the new buzz word in the weight-loss industry, but French women have been doing it for hundreds of years.
The Gallic relationship with food is a little like the schoolmate who insisted she didn't study before exams, yet got consistently high marks. As with their fashion, French women don't like looking like they tried too hard, even if it means balancing self-indulgence with self-restraint on a daily basis.
When a teenager, talking about their love life, tells you that they are "just texting", it's important to note that this is not a euphemism for a casual relationship.
They are speaking literally, not figuratively, and telling you, in plain terms, that this particular relationship has progressed to the point of using the face-throwing-a-kiss emoji, and perhaps the sending of the occasional nude.
The death of dating is just one of the cultural shifts that psychologist and author Jean M Twenge explores in her latest book, iGen: Why Today's Super-Connected Kids Are Growing Up Less Rebellious, More Tolerant, Less Happy - And Completely Unprepared For Adulthood. During her research, she discovered that only 56pc of high-school seniors in the US went out on dates in 2015, compared to 85pc of Boomers and Gen Xers. She also noted a decline in sexual activity among what she calls iGen, largely because they are more likely to be sitting alone in their bedroom, staring at the screens of their various devices, than leaving the house to - whisper it - meet people.
It's hard to wave the flag for dating which, let's face it, is inherently awkward and sometimes completely soul-destroying, yet it's worrying that this trend is emerging alongside the rise of virtual sexual encounters and sex robots.
What will relationships look like in 100 years' time? Will flirtatious eye contact in bars require consent? Will face-to-face become a bizarre fetish that you can only indulge in underground clubs in Berlin? Will skin-on-skin become illegal in three states in America?
The dystopian possibilities make the prospect of eating spaghetti in front of an incurable bore seem utopian by comparison.