people over 65 lived in an era of austerity and relative sense, food and exercise wise.

The 65 threshold is more notional, I suspect. If you set the threshold at 64, 63 etc you would see a decline asymptotic to a lower figure (by the difference the over 65s are above the median).

If you think about (UK certainly) the healthy diet endured during WW2 and similar scenario slowly diminishing after, the baby boomers have benefited. Couple that with the fact that we now pay about half the price for food than then (relative to average wage) the food we eat is more processed (not in Rouge Towers) - I think the conclusion is too obvious to state.

But on the racial/ethnic/religious front, I fear we have not made progress, more regress.