There's a big difference between "well fed" and "properly fed." "Well fed," to me, usually means "gets enough, or more than enough, to eat." "Properly fed" means "gets the right amount of food, and sufficient quantities of most nutrients."
People don't often die of starvation in the United States. I don't have exact numbers, but if you exclude people who have eating disorders, I'm sure it's insignificant compared to almost every other cause of death. But, malnutrition is certainly a problem, and that problem gets worse when you have people who literally don't know where their next meal is coming from.
Obesity in this country is closely linked to poverty. The foods that people in poverty have access to (because of cost but also because of food deserts) offer excessive calories but poorly balanced nutrition.
That means that people are obese but at the same time essentially starving to death from lack of nutrients. Which causes more food cravings that people are able to attempt to satiate only with more food with poor nutritive value.
I think obesity dis-proportionally affects impoverished African Americans vs. other impoverished races.
At least based on one point of anecdata - my neighbors. I have lots of poor families in my neighborhood even though I am middle class myself thanks to HOC (a Maryland social program where middle class housing is subsidized for the poor). Long story short - my poor African American neighbors are extremely obese; and it's no wonder why. I only ever see them eating McDonald's/dollar tree chips/soda. I know they are on SNAP, but I don't know if they are trading it for booze/cigarettes. It's my opinion though that they lack education on how to prepare/cook cheap raw ingredients into meals.
Yet my other equally poor immigrant El Salvadorian neighbors are skinny as rails and from what I can tell they eat tons of rice and beans and such (I often see them carrying 20 lb bags of rice into their house).
There is definitely a genetic component. A very clear example is the obesity rate of Pacific islanders after they were introduced to the western diet. They were genetically isolated while subsisting on a very specific diet for thousands of years. As a result, they no longer thrive on the same diet that Europeans do.
The people that run these organizations have an incentive to make this problem appear larger than it really is. I have never in my life seen in this country a starving person or a malnourished person for that matter and the government health statistics back me up. It is not a problem the U.S. has.
With so many billionaires in this country, poverty is not a problem we have. With so many condos by Central Park and mansions overlooking LA, neither city has a homelessness problem.
I am a fan of fasting, keto, and IF. But a sudden loss of daily calories for the unprepared can be severely physiologically damaging for many, no matter how much you have stored.