The heart-brain connection

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We all know that having high blood pressure isn’t good, but not many people understand (or appreciate) the link between high blood pressure and cognitive health. 
 
It’s something we might want to pay a bit more attention to. 
 
About one in four Canadians suffer from high blood pressure, and that number is expected to rise as the population ages. Health professionals are concerned. Much of the concern lies with the potential increase in incidences of a stroke or heart attack (just a reminder – heart disease is the #1 cause of death for women). 
 
And yet more and more health professionals are looking closely at the possibility that controlling hypertension might also help delay or prevent cognitive impairment. 

There seems to be general agreement that high blood pressure in middle age (40-60 years) is a risk factor for later-life cognitive decline, including overall cognition, memory and processing speed.  In fact, high blood pressure is one of the top modifiable risk factors for dementia.
 
What’s the link?
The brain is a highly vascular organ, meaning it has a vast network of blood vessels. It’s only two percent of our body weight, but receives 20 percent of our blood supply.  Blood provides the oxygen, glucose and other nutrients the brain requires for energy. 
 
Over time, high blood pressure, by putting increased pressure on artery walls, can damage the arterial walls via scarring and narrowing, leading to diseased arteries. This decreases the blood flow to many parts of the body, and of course the brain.
 
This is the type of situation that could lead to either a stroke, a variety of mini strokes, small areas of dead brain tissue, brain shrinkage, and possibly the plaques and tangles typical of Alzheimer’s disease.

The good news?
Many of us can manage blood pressure through our approach to one or more of the following:

  • Nutrition

  • Weight management

  • Exercise

  • Sleep

  • Stress management

 
Yes, there is always blood pressure medication, but trying to address it, at least initially, through lifestyle changes can help us get to the root cause of why we have high blood pressure in the first place.  Medication, on the other hand, tends to mask the cause. 
 
Having said that, genes and family history can play a big role, so some people have no choice but to go on medication.
 
Nutrition
The most often recommended eating pattern to reduce blood pressure is called DASH – Dietary Approach to Stop Hypertension. It’s close to the Mediterranean diet, as both promote an approach rich in vegetables, fruits, whole grains, nuts, seeds and legumes, and lower amounts of lean protein such as meat, dairy, poultry and fish. 
 
The DASH diet is a little more restrictive in that it specifies a reduction in sodium intake, whereas the Mediterranean diet includes more healthy fats, such as nuts and olive oil.    
 
I confess I find the DASH diet to be a bit too liberal with grains - both the number of servings and their inclusion of refined grains. Even though it states mostly whole grains, most of the guidelines for the DASH diet I looked at included refined grains. The problem of course is that refined grains turn into sugar once ingested, and ultimately into fat if our cells already have enough glucose/energy.  So one has to be strict on the number of servings and focus as much as possible on incorporating whole grains. 
 
One final note – there are studies that show that reducing carbohydrates with an increase in protein also decreases blood pressure. This is in line with the recent news about increasing our protein intake – that .36g per pound, the RDA recommended amount, is the BARE minimum, especially as we age. Ideally, getting approximately 25-30g/meal should be our target. 
 
And remember – two key things with protein are, one, spreading it out throughout the day, and two, making sure breakfast gets equal billing - some would say this is the meal where we should get the most protein. I know this can be a challenge - I tend to use protein powder when I’m not including enough protein at breakfast.   
 
Weight management
Being overweight is strongly associated with high blood pressure. It puts extra strain on our hearts, potentially damaging blood vessels alongside the increase in blood pressure. Even a modest reduction in weight can lower it.
 
Exercise is medicine
Exercise helps lowers blood pressure. Period. Regular exercise strengthens our heart, ultimately allowing it to pump blood throughout our body with less effort, and therefore less force on our arteries over time. 
 
In addition, exercise increases blood flow to our brains, meaning more oxygen and energy to the brain. And it ramps up our hippocampus, the part of the brain critical for learning and memory.  Note this is just scratching the surface on the benefits of exercise for our brains (and bodies). 
 
How much exercise?  The guidelines still say a minimum of 150 minutes of moderate aerobic exercise a week, although ideally, tucking in a bit more would definitely help. Think brisk walk, jogging, dancing, swimming, cycling… things that are going to get your heart rate up and ultimately strengthen your heart. 
 
Studies show that strength training can also lower blood pressure (as well as being critical for mobility and bone health, especially as we age). It’s recommended that one incorporate strength training at least 2x/week for best results all round. And with respect to lowering blood pressure specifically, moderate to vigorous intensity for a minimum of two months. 
 
My recommendation – try to do the strength training on top of the 150 minutes/week.  Start with once/week. I know it’s a big ask, especially for those who find it challenging to incorporate exercise into their schedule in the first place.  But I can’t stress enough - exercise really is medicine. On so many levels. Start slow and build.

Sleep (and stress and weight gain)
So how does poor sleep impact our blood pressure? One theory is stress. High stress levels can lead to poor sleep, and when we sleep poorly we become more stressed. A vicious cycle. Both poor sleep and high stress cause the production of stress hormones, including cortisol, putting us into a sympathetic (fight or flight) state. And what does cortisol do? It increases blood pressure. And weight gain.
 
Not only that, a poor sleep also negatively affects our hunger hormones, often making us crave high calorie foods during the day (and into the evening).  This also leads to weight gain. 
 
How to better our sleep?  You can start by reading this, which is more focused on improving sleep habits in general - or, if it’s stress related, read on.
 
Stress management
The link between chronic stress and chronic high blood pressure has been studied for years, and we are still learning.
 
There are many ways to try and manage our stress levels, but I won’t sugar-coat things and say it’s an easy fix. The good news is that many of these management techniques do work, but it takes persistence and dedication. Again, start small – and start with things that aren’t a big “barrier to entry” for you.
 
In no particular order, some suggestions are as follows. I’ve added links for you to explore if you want more information, rather than long explanations of each:
 

 
Bringing it back to the brain
We have to take care of our noggin!  (That means head for you younger generation ;-).  Good health doesn’t just happen – we have to work at it.  And every little thing we can incorporate helps.  Something as seemingly innocuous as high blood pressure can lead to a whole host of issues as we age. Start small but start now. Or, if you’ve already started, perhaps it’s time to take it to the next level.  Just know that if you incorporate a number of the things suggested above, you will do a lot more than simply lower your blood pressure - the upside is endless.
 
Thanks for reading :)
 
Gillian x