Flaxseed to Lower
High Blood Pressure
Wouldn’t it be great if a safe, readily available, inexpensive natural food could treat hypertension as
effectively as some medications? And wouldn’t it be even better if the only “side effects” were positive,things
like improving lipid profile, helping bowel function and reducing cancer risk? Well, preliminary resul presented at
a recent meeting of the American Heart Association suggests that such food does exist. It’s been a favorite of mine
for a long time. It’s flaxseed.
High blood pressure affects a huge percentage of the population. The fact that it rarely causes obvious symptoms
makes it even more deadly. People aren’t aware of the damage that’s being done until they suffer a stroke, heart
attack or other complication.
That’s why it’s important to monitor blood pressure frequently and if it’s high get it down.
Ideally, we control high blood pressure with lifestyle changes such as weight loss, healthy diet, stress
management and so forth. Often, however, these changes aren’t enough. Then treatment with medication becomes
Unfortunately, medications can have side effects. That’s what I was especially glad to see this report.
It’s interesting that the study was not originally designed to look for an effect on high blood pressure. The
plan was to see if flaxseed had any effect on the course of people with peripheral vascular disease.
There have been a number of observational studies suggesting that flaxseed and other foods high in omega-3 fats
can have a beneficial effect on the lipid profile which in turn might help people with problems with hardening of
the arteries such as heart disease and peripheral vascular disease. Many of the studies on omega 3’s have not been
the “gold standard” of a double-blind, placebo-controlled randomized trial. The researchers in Canada set this
particular study up to meet that standard.
They randomized 110 people with peripheral vascular disease into two groups. One group was going to get a daily
serving of baked goods containing ground flaxseed (the equivalent of about 3 tablespoons). The other group got the
same baked goods minus the flaxseed.
The researchers collected a lot of data on these folks. They recorded symptoms, physical findings, vital
signs and blood work and other tests. They measured blood pressure just because it was routine, not because
they are expecting any particular change.
Going into the study, about 80% of the people had high blood pressure. This isn’t surprising since high blood
pressure is a risk factor for developing peripheral vascular disease.
The study was intended to go on for a year. At about six months the researchers took a look at their
preliminary data. They were pleasantly surprised to note that there was a dramatic improvement in blood pressure in
the group getting the flaxseed.
On average, their systolic blood pressure dropped 15 mmHg and their diastolic blood pressure dropped by about 8
mmHg. This would be a great response if you were testing a drug!
In contrast, there was essentially no change in blood pressure in the group getting the placebo.
Looking at the results of blood work, the researchers found that the flaxseed group had significant increases in
alpha linolenic acid (a healthy type of fatty acid) as well as increase in levels of some potent antioxidants.
These changes didn’t occur in the placebo group.
It’s of note that the people who had normal blood pressure going into the study maintained normal blood
pressure. They did not develop abnormally low pressures.
I’ve long been a big fan of flaxseed for the other health benefits.
Years ago, I started reading about the benefits of omega-3 fats. At the time, I was predominantly interested in
their effects on vascular disease (not too surprising since I had a busy vascular surgical practice at the
After doing quite a bit of reading, the evidence impressed me enough that I decided I really ought to be getting
more omega-3’s myself. Sort of the idea that it would be good to practice what I preach.
I wasn’t all that keen on eating fish back then so I turned to flaxseed, one of the better plant sources of
I also liked flaxseed because I had seen some reports suggesting that the ligands in flaxseed may suppress the
development of some cancers, particularly breast and prostate cancer. Add to that the fact that ground flaxseed is
high in fiber, which most of us need more of, and flaxseed seemed a reasonable dietary addition.
I started grinding it up and adding it to my high fiber breakfast cereal. When I started, I didn’t really
expect to notice any particular changes, but several months later I did.
I used to have a real problem with dry skin on my hands and arms, especially in the winter. I attributed it to
all the handwashing and harsh scrubbing with strong antiseptics that goes with being a surgeon. Early in my career,
come January and February my fingers would crack just bending them and I’d wake up with blood on the sheets from my
elbows bleeding. It was pretty unpleasant. I tried all kinds of lotions and creams but nothing seemed to help
The winter after I started eating flaxseed regularly, that changed. I still remember the day I realized I
no longer had that problem. I was at the scrub sink prepping for an operation when I noticed my hands weren’t
sore and bleeding. It was like “Wait a minute... It’s February and I’m not dry, cracked and
chaffed> What’s going on?”
The only thing I could think of that had changed was the flaxseed.
I’ve taken it on and off ever since. These days I’ve cut back on grains and cereals, I eat salmon
regularly and take fish oil supplements daily so I’ve been more sporadic about taking ground flax. After
seeing this study, I thin I’ll get back on it.