Years ago, this incredibly simplistic dictum was taken as gospel by the medical profession. There have been a number of myths over the decades surrounding high blood pressure and I would like to clear up some misconceptions around this very important topic. Blood pressure is simply the pressure within the arteries when the blood moves as it is pumped. The typical designation for BP is systolic/diastolic. The systolic pressure is an indirect measure of the force of contraction of the heart whereas the diastolic pressure is the resting pressure between heartbeats.
For many years, hypertension was defined as a BP of 140/90 or higher. Any level above 120/80 up to 140/90 was considered pre-hypertension and those in this category are at a higher risk than those with a completely normal BP.
Recently, a panel of 21 specialists in the field published new guidelines for the American Heart Association and American Academy of Cardiology task force after analysing 900 published studies.
Hypertension is now categorised as a BP of 130/80 or above. In an interesting twist, the task force is designating blood pressures 120–129 systolic as being elevated BP but not designated high. Interestingly, the research is suggesting that people with a blood pressure in the 130 to 139 systolic range and the 80 to 89 diastolic range should also have a 10 year risk assessment for heart disease and if this risk exceeds 10%, medications should be considered and the person treated until the BP is normalised. Recent data has suggested we should be aiming for a BP level of 120/80.
These new guidelines are suggesting that 50% of the adult population have hypertension.
Following on from these guidelines is the new study of 412 adults with elevated blood pressure which was published in the November issue of the Journal the American College of Cardiology. This study suggested that following the DASH diet, which is a diet of fruits and vegetables, whole grains along with dairy, fish, poultry, beans, seeds and nuts combined with low salt reduces blood pressure more than pharmaceutical medication.
The study looked at 412 adults including 234 women whose ages ranged between 23 to 76 with a systolic blood pressure somewhere between 120–159 mmHg and a diastolic pressure between 80 to 95 mmHg. Over half were African-American.
None of these people were taking BP pills or Diabetic medication. They did not suffer heart disease, kidney disease, cholesterol elevation or diabetes.
The diet was continued for 12 weeks and the groups were also split into low salt, medium salt or high salt. For example, medium salt intake was considered the equivalent of 1 teaspoon of salt on a daily basis which is much lower than what most people living in our society would be ingesting.
Those individuals consuming the DASH diet alone had an 11mmHg reduction in systolic pressure if their initial systolic was 150 compared with a 4 mmHg reduction if their systolic pressure was less than 130.
But, when the researchers reviewed the people with the highest systolic blood pressure of 150mmHg also on the low salt arm, there was an average reduction of 21 mmHg compared to the high salt, control diet. This is actually better than most BP pills alone. Commonly used drugs such as ACE inhibitors, beta-blockers & calcium channel blockers would typically reduce systolic blood pressure by somewhere between 10 to 15 mmHg.
This study reinforces the vital importance of lifestyle modification for the management of hypertension, no doubt, the most important cardiovascular risk factor.
The most powerful lifestyle factors to reduce BP are as follows
1) Weight loss and in particular loss of abdominal fat
2) Regular exercise — 3 to 5 hours weekly
3) Markedly reduce the intake of sugar and salt
4) No more than 1–2 standard alcoholic drinks per day
5) Stress management techniques such as regular meditation
Kyolic aged garlic extract, two daily has been shown in a randomised controlled clinical trial of 88 patients with mild hypertension to have a significant reduction in BP similar to a standard pharmaceutical drug.
Bergamot polyphenolic fraction — One pill twice daily of the 47% polyphenolic extract has been shown to have an antihypertensive effect.
Two small pieces of dark chocolate, > 70% cocoa has been shown in a Cochrane review to have a reasonable effect on reducing blood pressure and improving blood flow to organs.
Management of sleep apnoea through either mandibular advancement devices or nasal CPAP has been shown to control BP in affected individuals.
Pharmaceutical therapy is also often necessary but unless there is evidence of end organ damage as seen typically in the heart, the kidneys or the blood vessels in the eye (a good marker for what is happening in the blood vessels in the brain), lifelong drug therapy should not be commenced until all of the other avenues have been utilised.
Regardless, hypertension is the most common cause of stroke and over the age of 60, heart attack. As we collectively become more educated about the vital importance of managing hypertension and bringing in measures to do so, we will see the rates of these devastating diseases markedly reduce. Unfortunately, at present, cardiovascular disease is still our biggest killer.