The most efficient (and cheapest on the long term) health system is one that makes sure, people are not getting sick in the first place, rather than only focus on the treatment (still important of course).
One of the most important factors for longevity (even though we are getting older, we spend more time with “sick” years) is nutrition (and exercise). There are many different approaches and problems around this, trying to sum up a few:
(i) Nutrition recommendations. The current recommendation (often still the food pyramid) is heavily influenced by big cooperations, every recommendation that still include animal products is not acknowledging science. Big efforts of physicians in the US at least managed to change it to the “nutrition plate” (you can find more info at: www . choosemyplate . gov) which does not directly mention meat anymore, however the dairy industry still managed to let dairy be included. However, its not about to forbid eating animal products, but encouraging it is as stated above is a purposefully wrong-leading.
(ii) Nutrition Education. Based on the previous paragraph, we need a broad, free accessible, low barrier education on nutrition. These can be measures video-series free accesible on a homepage, but also bringing (science based!) nutrition education into schools. Junk Food is advertised heavily to children and families, super heroes that are connected to them, have you ever seen big corporate money in healthy food? Unfortunately not, because there is not much money you can get out of it.
(iii) Advocating for more nutrition education within the curriculum of medical students. A recent article by the washington post showed once more (and I can unfortunately approve as a medical student) that physician are right now not the best persons to talk to when its abouut nutrition.
Beside nutrition, also Sexual & Reproductive Health is an effictive measure:
(i) Supporting countries in providing free HPV vaccination for female (& male!) youth in Europe
(ii) Supporting comprehensive Sexual Education programs
The main message I want to stress out once more. Even though preventive medicine is expensive in the first place, it will always save huge amounts of money on a long term. So beside specific measures we could also try to have a baseline that urges countries to spend a minimum amount of their GDP to use for public health/preventive medicine (even though I personally prefer proposal for different measures, rather than setting a certain amount from their GDP)