Yes, narrowing is an aging process, but it is accelerated by using too much fatty diet, or sugar, so it can cause an early narrowing of blood vessels.
Lack of exercise does not burn fat/cholestrol/sugar in your blood and result is increase in weight, also termed as obesity.
The combined action of the above factors results in premature hypertension
, heart disease
and kidneys and brain.
SO DO PHYSICAL MORE AND BURN YOUR CALORIES, AND EAT A HEALTHY DIET.
The cause of dizziness
can be evaluated by your doctor after checking your BP and running a couple of blood tests, depending on age and family history.
The best exercise is walking as much as possible, however your doctor can guide you about the nature of exercise, keeping you age, height and weight in view.
Don't go for drastic measures as they will be harmful.
Hope answered your question.