I agree with her about healthy eating, but I doubt she was thinking of low carb.
But she didn't mention the role poverty has in obesity. Many of us in rural areas get food from food banks & also have EBT cards. You can buy a lot more food if you're eating cheap foods such as macaroni, rice, potatoes, bread, & so on. And if both parents are working, convenience foods play a big part in the diet because no one has the time to cook from scratch.
When I get our boxes of food from Rural Resources, I keep the cans of tuna & chicken, the cartons of milk, and anything else they put in the box that's healthy. I also keep the macaroni, rice, breakfast cereal & bread, but I feed it to the chickens. The fruit juice (2 gallons/month!) & canned fruit & vegetables get re-donated to the food bank.
I have a garden, but it takes time to grow & process home-grown vegetables. Many people I know haven't the time or energy (many are my age or older) to do that.
I think it's telling that for a small town like ours (5k in town, about the same number in the surrounding area), there are multiple fast food places, including about 5 pizza places. And like so much of the US, people are eating & drinking almost constantly during the day. I'm always amazed by the amount of food at our Franciscan gatherings. We meet at 9 & there is food. An hour & a half later we break for an early lunch. Then at the end of the meeting people are eating more - I suppose so they don't faint from hunger on the way home. I've sometimes mentioned that our founder, St. Francis, didn't eat like we do. No one seems to get it.
My fellow diabetics eat tons of carby foods & cover with meds or insulin. One lady I talked with said she didn't eat carbs, but I think she was thinking of sugar & candy - her plate was loaded with pastries.