140/90 is the upper normal range if your BP is less than or equal to that..and at this age you can control your BP by diet and exercise.
But you also need to understand the concept of hypertension
Many factors can affect blood pressure, including:
1) The amount of water and salt you have in your body
2) The condition of your kidneys, nervous system, or blood vessels
3) Your hormone levels
You are more likely to be told your blood pressure is too high as you get older. This is because your blood vessels become stiffer as you age. When that happens, your blood pressure goes up. High blood pressure increases your chance of having a stroke, heart attack, heart failure,
kidney disease, or early death.
I read your query, by the information i have in hand my advice to you would be
1) Keep a BP daily record for at least thrice week
2) Basic tests should be one to rule out cardiac issues
3) unless any recent evaluation has been done I would advice these test
ECG
ECHO
Lipid Profile
TSH
Diet and exercise is advisable for you age
DASH stands for Dietary Approaches to Stop Hypertension. It is an eating plan that is based on research studies sponsored by the National Heart, Lung, and Blood Institute (NHLBI). These studies showed that DASH lowers high blood pressure and improves levels of cholesterol. This reduces your risk of getting heart disease.
The DASH Diet
Emphasizes vegetables, fruits, and fat-free or low-fat dairy products.Includes whole grains, fish, poultry, beans, seeds, nuts, and vegetable oils.Limits sodium, sweets, sugary beverages, and red meats.
Along with DASH, other lifestyle changes can help lower your blood pressure. They include staying at a healthy weight, exercising, and not smoking.
Get back to me with a detailed history and old / new records for a better individualized advice.