As children grow, they are of course exposed to their own physical changes. This is natural. Also people around them, not the least of which is their peers will talk about their changing shapes. What constitutes attractive looks etc. All of this is to be expected and parents cannot stop the chatter that goes on around body image.
So join it!
However, one great support in reducing anxiety in this area is to engage your children in active sports over their growing years. The more a child grows with interest in being physically stronger, the greater they look to developing a body image built around being healthy and productive. I have seen this time and time again. I noticed that children who loved and gravitated around sports were more inclined to associate with children who had similar interests. Their conversations were about building strong bodies to do better times on the track, in the pool, on the waves, on the basketball court, etc. They developed a stronger self-awareness of body image and were more educated and interested in learning how healthy bodies worked. They of course were given supportive advice through clubs and training sessions and enjoyed talking about how improving their stamina would give them the body they wanted.
I have seen this in my own children and now grandchildren who are keen to associate with like minded children who talk about feeling good as being as important as looking good. The self-discipline they gain from being part of teams and the social comradery protects them from the murky world of social media and “looking pretty’. Attractive to them is tied up with a having a healthy body that works well.
My recommendation is simple. Involve the children in organised sport from an early age. This may mean exploring different sports until as a family you choose one that provides an environment in which you feel happy and secure as you will be handing your children over to coaches and supportive parents on a regular basis. There is often a like mindedness in these clubs and this continues to support healthy images about the body across groups of likeminded parents. There is also strong modelling from parents who have a love for being fit themselves. One warning! Ensure the club is a positive one promoting competition on a healthy level. This does need to be assessed by yourself as parent.
Once the child sees their body as something that is beautiful by nature of being healthy and fit, they are comfortable in their own skin and steer away from the shady world of social media presenting unacceptable images. Their social world is more about associating with likeminded children well educated in how the body works. They value a healthy mind and body. To them that is beauty.