From the article quoted by the OP:
Wall Street "forced food companies to try and sell food in an extremely competitive environment," she says. Food manufacturers "had to look for ways to get people to buy more food. And they were really good at it. I blame Wall Street for insisting that corporations have to grow their profits every 90 days."...
Yes, the problem is definitely caused by the lower price of food, mostly junk food in the US, no doubt about it.
Our recent RV trip took us up to Banff. Though we had been to Canada several times before, this was the trip when we stayed the longest, and had more chances to observe the daily life there.
I saw that the cost of food, both served in restaurants and sold in grocery stores, ran something like 1.5x to 2x the prices in the US. As an example, I saw an avocado sold for $2.99 in Banff. A small 16-oz tub of salsa went for $5.99! I should have taken photos as proof.
And my observation was that the Canadians seemed a bit less heavy than the Americans!
Similarly, visitors to Europe cannot help noticing how the Europeans are thinner than US citizens. Of course food there is also more expensive. It is that simple: expensive food means people eat less. The Europeans also walk more.
In third-world countries, food may seem cheap relative to the cost elsewhere, but in terms of the income of the local people, it is not. People in poor countries spend a higher percentage of their income on food than people in developed countries do.
So, what is the solution? Should the gummint tax the daylight out of junk food, candies, [-]sugared[/-] soft drink, high-carb snacks? Could we trust the gummint to keep that money to pay for healthcare? What have they done with the cigarette taxes?
I have read that healthy veggie and fruits are expensive in inner cities, and poor people may not have access to them. Could be true as I do not live there. However, I live in the outskirt of a metropolitan area with a population of 5 million. A grocery store near us has frequent sales of 5 avocados for $1. Yes, they are a bit smaller than the "premium" kind, but taste just as good. So, I have 2 instead of 1. There are plenty of other veggies such as squash, zucchini, cabbage, etc... that one can get for around $1 per pound or much less.
Question: If people do not want to eat healthy, how do we force them to? Is this still a free country where people can choose their food, among other lifestyle choices?