Gluttony and obesity is a problem in American culture. This is an addition. God can heal you, seek him in prayer and faith.

Just sign them up for a 21 days fasting and prayers to God in Jesus name- 6am to 6pm. Lol.
These are the benefits : develop spiritual intensity(power) ,loose weight , recieve answers to prayers and gain appetite /self control. Wanna try? Talk to your doctor first.

I do not think people seek physical or spiritual health as much as they do to be 'happy' and there are many spiritually and physically unhealthy choices that, in the flesh, give us this fleeting feeling of 'happiness'

I dont know that it will change, as we move forward trying to seek happiness above all else and trying to make life lived as effortless as possible, we are moving toward more automation and AI which will make our physical activity even less, and we keep pushing for more and more 'happiness' which will often come at the cost of our spiritual and physical health

the more we move toward an ideal of being 'freedom' centric ... the more often people will be leaning on their own poor choices .... its just where we are.

Happiness is fleeting...joy is permanent.
God the Holy ghost saturates our spirit,soul and body with joy. He is the source of everlasting joy(Galatians 5 v 22)
When you have his joy flowing from within ,you'll naturally be happy.

Happiness is in your circumstances. Joy is having that personal spiritual relationship with Jesus Christ!