When you’re insulin resistant, that is,
you’ve got metabolic syndrome, pretty much every chemical in the body is NOT QUITE RIGHT.
Some are up. Some are down. Few are actually at physiologically NORMAL levels. Traditionally
the focus is on the big guns. Sugar, insulin and cholesterol. In this series, we take a
look at some of the other players. Who they are, what they’re up to and how they’re
part of the state of insulin resistance. This week, we feature ALDOSTERONE. Now, aldosterone
is an UPPER. It’s levels are typically HIGHER, than normal, in someone who is insulin resistant
and it often goes, hand in hand, with high blood pressure. So what exactly is it ? Well,
aldosterone is classed as a mineralocoticoid hormone. It’s derived from cholesterol and
produced by the adrenal glands, these are the little glands, perched on top of the kidney.
It’s BIG job – is to regulate the body’s salt levels. This is quite important, because
sodium is a mover and shaker. Quite literally hundreds of transporters, dotted all over
the body, use the movement of sodium ions, as the vehicle to move things across cell
membranes. In by gone times, before the advent of processed foods, sodium was a rather scarce
resource. So aldosterone had to work hard. The way aldosterone helps the body, hold onto
sodium, is by acting on the mineralocorticoid receptors, specifically the ones, stuck in
the tubules of the kidney. Now, this encourages the kidney to hold onto sodium and to pee
out potassium. Which in by gone days, was rather pervasive. And potentially toxic. In
the process, of holding onto sodium and eliminating potassium, water ends up being is reabsorbed,
and this, is what impacts blood pressure. You see, the water fills up the pipes and
these have a fixed capacity. So when blood pressure is low, the filling of the pipes
is most helpful. Of course, if the pipes become TOO FULL, the extra liquid, has “nowhere”
to go, so the blood pressure rises. So aldosterone levels are carefully controlled. By several
systems. Most notably. The renin-angiotensin-aldosterone system or RAAS for short. This system is triggered
when there is a drop in blood flow to the kidney. The other important regulator of aldosterone
levels, is the HPA axis – this is a hormonal system which connects the hypothalamus and
pituitary, which are in the brain and the adrenal glands. This system, fires up every
day, as part of your circadian rhythm, but it can also be triggered, when you face a
particularly stressful situation. So in a nutshell, aldosterone is a “stress” hormone.
Now, the stresses that trigger it’s release, are quite variable, they include severe blood
loss, severe anxiety. Shock, brought on by, either physical or emotional trauma. A shortage
of sodium or an excess of potassium. And well, insulin resistance. Mmmm not sure if you’ve
ever thought about the fact that insulin resistance is to all intents and purposes, a stress response.
This explains why stress hormones, like aldosterone are elevated. So what ? Well most of the stresses
I listed are beyond your ability to control. But having said that, you can nudge your aldosterone
levels lower. Now one of the ways to do this, is through meds that interfere with the RAAS
pathway. They will lower your blood pressure, but won’t do much to alleviate the “stress”
response. In actual fact, they’ll keep it firing. To actually lower the stress response,
you need to target, the actual stressors. There are two levers, you can pull. The first
one, would be to manage your sodium levels. Remember TOO LITTLE sodium, not too much,
is the stressor. The second, is to manage your insulin levels. Studies have shown, insulin
acts directly on the adrenal gland, bumping up the production of the adrenal steroids.
Here are a few of the journal articles I’ve used to tell the aldosterone story. Thank
you so much for watching and I’ll see you next time, remember small things can make
a big difference to your health.