The actress tells Yahoo Style that being married to Olivier Martinez means she doesn't like to dress down.
"I have definitely changed as a result of being married to a French husband," says Halle.
"French women would not put their sweats on and run out to the market. So I care more about what I wear out of the house, because if not, he calls me out on it."
But Halle, 48, said that the French fixation on looking good not only extends to what you can see on the street but what you have on underneath.
"[French women] put a lot of energy into their outerwear, but also their underwear," she says.
"They're not going to get caught in an emergency room without being prepared."
But Berry – who has memorably undressed for films such as Swordfish and James Bond – credits her mum for introducing her to a secret weapon against sagging.
"She said if I don't want my boobs to hit my knees by the time I'm 30, always wear a bra, even to bed," says the mother-of-two.
Halle's candour about her underclothes comes as she helps relaunch Scandale Paris – an 82-year-old lux lingerie line the Oscar-winner has bought into after discovering it whilst walking through the streets of Paris with her husband.
But the actress says her new entrepreneurial venture is all about making sexy lingerie available to everyone.
"I thought, who can really afford expensive underwear?" said Berry.
With money in mind Halle collaborated with Target for 10-piece Scandale Paris intimates collection that will feature items ranging from $7 to $18 which will hopefully see the 40-something-year-old actress transition from movie star to business mogul.
Opening up about aging in Hollywood Halle says she's intentionally made plans to overhaul her career.
"As an actor, you face having to age and redefine yourself," she said.
"The roles you were able to play before, you can’t play anymore. So you have to adapt and play a different role. And as actresses, we need to accept that we’re not always going to be the sexy ingénue, but hopefully we get better with age. We improve our craft.
We have to be happy where we are and not try and chase yesteryear, because that's when it becomes problematic."