Calcium, bones and osteoporosis

I would like to make a review of the evidence about this subject.
Every time I tell that I do not eat a lot of dairies, no milk except for completely fermented goat raw milk from time to time when available, there is one guy who asks:
"do you care for your bones?"

Bones are solid organs made of proteins.
Calcium is a part of the structure but not the structure itself. Take a chalk and try to break it: very easy to do! The same applies to calcified bones without proteins!

1 You need proteins

"Protein makes up roughly 50% of the volume of bone and about one-third its mass"
You will find in Dysnutrition the amount of protein that you need in order to keep your muscle mass and BTW YOUR BONE MATRIX.
http://ajcn.nutrition.org/content/87/5/1567S.full.pdf+html
Bones are complex structure and as for other organs you need some vitamins, other micronutrients and growth factors to grow and maintain them optimally.
- Vitamin D
- Omega 3 fatty acids

Correlation between the mean daily intake of total omega-3 fatty acids and the percent change in urinary N-telopeptide excretion from pre–bed rest values (n = 16, Pearson r = −0.62, p < .01). The intake of omega-3 fatty acids for each subject is the mean daily intake over the first 60 days of bed rest.

2 you need Vitamin D

You will find in Dysnutrition all informations to talk to your health practionner 

3 you need W3 PUFA

Fish but fatty fishes...

4 you need exercise

Think to bones like muscles, if you don't use them they will atrophy, both muscles and bones. So exercise with all your muscles and please don't tell me that you walk!

Exercise is a workout which is relevant when you are unable to speak during effort...
http://www.bbc.com/news/health-28400968

Oups I forgot Calcium... You don't need to change because you probably eat too much of it!

I suggest you to mix diet and exercise in order to maintain your bone health!