I started watching that course through Yale University about The Psychology, Biology, and Politics of Food. It's great! Of course, it confirms a lot of what I already knew and thought.
Here is a link:
The module I just finished compares the food environment and human body of our ancestors with the current situation. He talks about how hard people used to have to work to get food and how starvation was a real threat whereas today food is every where and overnutrition and obesity are much bigger threats than undernutrition.
They have studies where they make available to lab rats more nutritious food than they could ever eat. These rats eat a normal amount of food and maintain a normal weight. Then they give lab rats an abundant supply of oreos, cheetos, etc--a variety of junk foods--and these rats triple their weight fairly quickly. It's biology--our bodies, like those of the rats, are programmed to go for the fat, sugar, and variety because that's what helped our ancestors stay alive.
Also, if they give the lab rats, just a ton of oreos, they get sick of them. So a key factor is a variety of junk foods.
Apparently, the same thing has happened with the Pima Native Americans in Arizona. They used to be poor and live a traditional life. Then they got the right to open the only casino in Arizona. Guess what happened? With wealth, this population of Pima Indians became obese and with that came an overabundance of chronic diseases like diabetes.
Nearby is another Pima community not a part of the casino. They on average weight 60 pounds less. They are almost identical genetically, but have far fewer chronic diseases.
The difference is in the availability of junk food and the amount of exercise.
One population is sedentary and eats junk food. The other has to work (exercise) and eats a more traditional diet.
By the way, our bodies also tend toward being sedentary b/c conserving energy was another way our ancestors stayed alive.
So one question that came up during the lecture was is educating people about nutrition and exercise enough? If our biology is set towards being sedentary and eating junk foods, is knowledge enough? He made the point that some people can resist, but fewer and fewer can or do, as foods are everywhere and processed foods contain more and more fat and sugar.
It made me revisit the idea of balance and diet. A lot of people advocate for giving kids some exposure to junk food so they aren't overwhelmed when they leave home. Also, most of our public service dollars go toward education--telling people that smoking and junk food are bad for you, etc. But if the environment coupled with the marketing and availability (remember the rats didn't even have marketing or peer pressure or economics....just availability) is so powerful, the question of whether education and moderation is enough is important. Maybe it's the environment that needs to be changed. That would take a miracle in the US--to get the economic forces to sway toward healthy foods and away from junk foods..... If only the health costs of junk foods could be included in the price....I think that could make a difference eventually....
Still here even (Australia) with cigarettes at $17 a pack, people smoke. I see people smoking and wonder How can they afford it??