Far from it Rolfe!!!
Why do you think the obesity epidemic is growing? There are people out there who do eat lots of processed food, fish and chips and MacDonalds on a daily basis, week in week out and year in year out. They don't seem to know any better and this coupled with a lack of exercise signals obesity and vitamin and mineral deficiencies with everything in the body working less efficiently.
Did you ever watch Supersize Me? This American guy lived on MacDonalds food for a whole month. He had a cardiologist and a DO who were looking after him during this time and he underwent a full medical exam and had bloods taken beforehand and everything was in normal range. After a month, his weight had increased by 2 stones, his cholesterol, which was normal before had increased to about 6 and most worrying was his liver enzymes, which had increased to dangerous levels, as if he had been consuming too much alcohol. The medics informed him that if he had continued this diet he would have had liver damage. By the end of the month, he felt unwell, had poor skin and had no energy whatsoever. Once he went back to his normal diet and started to exercise again, he felt better and did eventually loose the excess weight that he had put on.
This is an extreme example, but there are people like this around and couch potatoes who eat a very poor diet all the time that is highly processed, with a lot of saturated fat and sugar can be at risk of obesity, diabetes, stroke, heart attack and vitamin and mineral deficiencies because they can not get what they need from the quality of the food they are eating.
I do believe the saying that "you are what you eat".
I am lucky in my work as a Physical Therapist and Sports Massage Therapist, that I do a lot of work with athletes who are in very good physical shape. They like to keep that way too.
So no Rolfe, it is no a lot of "woo-woo nonsense" as you put it. It is a sad fact and a reality of life.