----------Don Wiss wrote

Not really. In general vegetarians aren't so bad off, not from not eating
meat, but because vegetarians tend to not smoke, and they tend to not
consume sugar, coffee, alcohol, and soft drinks. They also tend to consume
more vegetables and less refined carbohydrates.

Don.

39 diseases to 137 (in meat eating pop.) is a huge difference.
Vegetarians very often do eat lots of grains and dairy, which wouldn't be able to make
them so healthy according to paleo assumptions as far as I'm familiar
with them. Most of the vegetarians I know do drink coffee and some alcohol and do consume sugar. Meanwhile I do know meat eaters who
avoid (added) sugar and don't drink coffee at all.
In anyway meat (in the amounts consumed in the western world) might still well be the reason or at least an important factor in causing the difference. 
Regards, Semira