All 5 of my parents' granddaughters are now married (and what an inspiring quintet (quintuple?) of young women they are). Thinking about my mother I thought I'd mention some of her battles with the (self-appointed, pseudo-) experts.
1. My mum insisted that butter was healthier than margarine, against the "experts" put up by the processed food industry. This has recently been proved right. She was also strong on the importance of other particular foods: brains (from sheep) and liver. Her ideas on these things come down from her ancestors. It is shocking how easily we abandon traditional knowledge these days. Expertise used against traditional knowledge needs a high standard of proof.
2. My mum was a great believer in the health benefits of sunshine. This has been proved right, though the anti-sun propaganda continues to push the damaging zero-sun policy. I should say that my reading leads me to believe that this is not just about vitamin D. The body uses UV to break down toxic organic molecules in the blood. This is extra important for people (like me) whose liver is not working 100%. An example of this, that is not in dispute, is bilirubin that causes jaundiced babies.
3. My mum was a strong believer in fresh air in houses. We are faced with a strong push from the Green movement for housing to be built tight as a drum and heated and cooled with heat pumps. I think my mum will be proved right again. Even if you are not in a Radon area (are you sure?), sealed houses get various sorts of toxic build up. All my life I worked in air-conditioned offices and I'm very pleased to have escaped that.
[update: The point I forgot to make is this: The expert brand is badly tarnished. This needs to be addressed by creating an environment where: (a) There is an open vigorous investigation of facts that are relevant to public policy and people's lives; (b) This needs to include nailing not only false claims, but also identifying those who are trying to deliberately mislead (this has to be seen to be impartial); (c) Identifying the real experts who know the facts and the relevant mathematics.]