TheKnightVigilant makes a good point about the possibility of sleep apnea.
I know several people who went to the doctor because of heavy snoring and have been diagnosed with sleep apnea. They now use the CPAP machine. It was cuмbersome for them at first, but they no longer snore and all say that the have much more restful sleep. Before using the machine, they always looked so tired whenever I would see them, now they are full of energy.
Also, all of the the people I know who have sleep apnea are overweight men. One lost a good deal of weight and no longer needs to use the CPAP machine.