We might be prone to certain diseases or disorders based on our heritage and genetic make-up, but often it is our lifestyle that tips the scales. Type II Diabetes is often given as an example here. Just because diabetes runs in your family does not necessarily mean you will have it, but it does make a person more likely to contract the disorder than someone who does not have a family history of diabetes. Eating a healthy diet, maintaining a healthy weight and staying away from excessive sugar on a regular basis can help. Of course, a person could do all these things and still have diabetes, but any lifestyle choices will shape the effect and manageability of the disorder.
To paraphrase: Though genetic disposition can create a greater likelihood of the onset of certain diseases and conditions, lifestyle can be the determining factor in deciding a person's physical health relating to these dispositions (predispositions).
Example: If a person is genetically disposed to be at risk of developing anemia due to the sickle cell trait, he or she can avoid developing anemia by adjusting diet to include significant amounts of iron.
Your body and quality of life is affected by who you were when you were born and what happened to you in your life. You can be genetically pre-disposed to something like heart disease, but if you eat well you can avoid it. However, if you eat a lot of salty and fatty foods, you will be shooting the gun and causing your heart problems to be more likely.
That is a very interesting quote. However, it seems to be a loaded one because the emphasis in the wording suggests that a trigger will be pulled one way or another--as if peaceful people will also pull a trigger at some point in their lives. I like post #2 for applying it to another situation other than guns, though. As far as health is concerned, there are certain risk factors that can accelerate the production of a disease as stated above. This brings up the social question of Nature vs. Nurture. How much do our genes affect our behavior? Does a child learn to hit someone else by being hit, or is it just nature for us to want to solve a problem by hitting? There certainly must be a balancing act between the two (nature vs. nurture) because someone can have a talent for singing whereas someone else might not. However, could the talentless singer purchase lessons and win in a competition over the talented singer? Sure.
What this means is that the genes that you inherit make you more prone to having certain medical problems (since this is in "Health" I assume that is what you are talking about). For example, if you have a family history of diabetes, you may be more likely to get that disease. In that way, the "gun is loaded." But you might not actually get diabetes. If you are very careful with your diet and lifestyle, you can put it off. Conversely, if you are not careful, you can "pull the trigger" and cause the disease to happen.
What an interesting quote. This quote definitely holds true to what it is describing. What this quote is describing is the way we live our life, and how our choices affect our health. However, sometimes no matter what our choices are our genetics can get in the way and sometimes throw a wrench in our plans.
For example, if someone has a family that has a history of diabetes, an individual can eat a healthy diet, exercise regularly, and monitor their health to help prevent diabetes. The genetics load the gun (the family history of diabetes) and the lifestyle pulls the trigger (not having a healthy diet and exercising leads to an increased risk of diabetes).
Hope this helps!