You probably know this, but the best plan is to eat smaller amounts on a more frequent basis.  I am hypoglycemic, so increasing complex carbs in connection with quality protein and healthy fats (Omega 3 found in fish, for example) should make a difference. 

This part is key:  avoid foods with simple carbs (yes, they are popular and effective for some), but stay away from any refined flour/sugar products and instead choose fresh fruit combined with natural fiber (veggies, grains, beans and so on). 

I do eat before running, but it is limited to 1/2 fruit and 1/2 granola and sometimes 1/2 protein serving of some sort.  Remember to combine/eat complex carbs with protein for better results.  Also, look at some supplements (not the ones with unknown ingredients or the crazy energy drinks with side-effects).  Try going to your local health food store.  They are usually very informed and helpful in recommending certain products.  Natural carrot or cherry juice might be good options to try.  They should help stabilize blood sugar levels with some other added benefits. 

Wishing you all the best.