Why don't Jigsaw w/SRT tablets dissolve in water?

In several of our formulas, including the top-rated, best-selling MagSRT® (aka. Jigsaw Magnesium w/SRT®), we use a proprietary Sustained Release Technology (w/SRT®) tablet.

You could also think of these as "slow release" or "time release" tablets.

Over the years, we've had customers put our SRT tablets into a glass of water, and then watch them sit there and pretty much do nothing.

They ask us, "My pills don't dissolve in water, does this mean they're ineffective?"

They assume because the tablet doesn't break down in a glass of water, then it's not breaking down in their GI tract, and therefore, it's not being absorbed.

And on the surface, that's a very logical assumption.


MagSRT was not designed to break down in water, nor was it designed to break down quickly.

In fact, we purposefully decelerated the release of nutrients.


Well, in the case of MagSRT, magnesium has "hydrophilic" properties. 

(That's just a a fancy word for "attracts water", sort of like a magnet.)

So when you ingest -- or "dump" -- magnesium into your gastrointestinal (GI) tract, the magnesium draws water into your GI tract.  

But the GI tract can only hold on to so much water for so long until well, you know what...

A serious laxative effect occurs, usually when you don't want it to.  

(Btw, this is how laxatives like Milk of Magnesia® work -- they're taking advantage of magnesium's "hydrophillic" properties.)

Jigsaw's SRT tablets are purposefully designed to break-down slowly so that your body can absorb the magnesium over an extended period of time, rather than trying to deal with a "flood" of magnesium in a short period of time.

This may seem counter-intuitive, but we designed it this way so our customers could take a large dose of magnesium once (or twice) per a day.  And for most, it helps keep them regular without feeling like a harsh laxative.

Our lab utilizes "dissolution testing" to ensure that the tablet breaks down over an 8 hour period.  

And these dissolution tests have three major differences from a glass of water:

  • Fluid -- the dissolution fluid includes a mixture of sodium chloride, HCL and pepsin to simulate what is found in the GI tract.
  • Temperature -- the temperature of the fluid is between 95 - 102 degrees F (35 - 39 C), simulating the range of the body's natural internal temperature.
  • Movement -- the fluid is constantly moving (between 29 to 32 revolutions per minute), simulating the peristaltic movement of the GI tract.

Here's what the lab results show:

View Downloadable PDF of Jigsaw Magnesium w/SRT® Dissolution Profile Lab Results

One Final Note...

There are many smart, well-to-do health professionals that encourage consumers to stay away from tablets entirely, generally on the basis that tablets don't absorb as well as capsules, liquids, or powders.

And for the most part, we totally agree with that sentiment...

...except, for instance, when it makes sense to  decelerate and sustain the release of the nutrient so the body can absorb over time as it travels through the GI tract.  And that's what we do with MagnesiumB Vitamins, and 5-HTP.

If your doctor has told you this, we respectfully ask that you pass this article along to them so they can get a fresh perspective on why sometimes, tablets could be the preferred option. 

PS - If you happen to see an undigested SRT tablet in your stool (which does happen to some customers from time to time) this is likely a sign that your GI tract is running low on digestive enzymes and/or probiotics. 

If this happens to you, we'd encourage you to talk with your healthcare professional about adding high quality Probiotics and/or Digestive Enzymes to your regimen.

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