Wow, lots of bad advice here. But here goes:
Blood pressure changes constantly. An isolated reading doesn't necessitate the need for meds. However, consistent readings do. Buy an automatic blood pressure cuff. Take it three or four times a day for two weeks. Once before each meal and again before bed. Write a log and take it to your provider. Be honest, no trying to fudge the numbers or changing lifestyles. Also record your pulse. Give this information to your provider so they can get an accurate idea of what is going on over time.
If your blood pressure consistently runs over 140 systolic, you're going to start medications; likely starting with an ACE-Inhibitor. If you do not want to take the meds long-term, lifestyle changes are necessary. No stimulants, no caffeine, and most importantly lose some weight and get regular exercise. Exercise will help your body's blood vessels remain elastic so that when your body compensates with extra blood flow, large amounts of pressure doesn't follow suit.
If you can't maintain pressures in a normal range without medication, just accept the medication so that you don't have stroke, heart attack, or fry your kidneys. If your labs show proper electrolyte balances, don't try to change your diet to "high potassium" or something like that. Your body has a way for remaining in homeostatic balance so long as your organs, particularly kidneys, are healthy.
Good luck!
