In most cases, there is no single identifiable cause of high blood pressure. This type is known as primary or essential hypertension and develops gradually over many years. However, several factors are known to increase your risk. These include being overweight or obese, eating too much salt and not enough fruit and vegetables, not exercising regularly, drinking too much alcohol or caffeine, smoking, not getting enough sleep or having disrupted sleep patterns, being over the age of 65, and having a family history of high blood pressure. Certain ethnic groups, including people of African or Caribbean descent, are also at higher risk. In some cases, high blood pressure can be caused by an underlying condition such as kidney disease, hormonal disorders, or the use of certain medications including the combined oral contraceptive pill, some herbal remedies, and non-steroidal anti-inflammatory drugs. The NHS provides a full list of risk factors and causes that you may find helpful to review.