The Input Pathways Of Mannitol Lead To Differing Consequences
Whether orally or intravenously, the route of ingestion makes a huge difference.
Mannitol is a sugar alcohol that is used as an artificial sweetener for diabetics to enjoy indulge their sweet tooth cravings. An overconsumption of mannitol may also result in the development of bowel spasms and diarrhoea.
Interestingly, it also is a diuretic — it has been shown to help with acute brain swelling in some situations, and it can also aid in increasing urine output to better balance out fluids in people with acute kidney injury.
And therein lies some confusion — people tend to think that mannitol is harmful and shouldn’t be touched. But yet others do think that it’s fine to consume mannitol. What’s the difference?
The difference lies in the route of ingestion
Mannitol is a sweet tasting substance, and that’s why it is an option that diabetics may choose to sweeten their foods.
Because mannitol traverses the intestines almost untouched. It is said that:
The chemical structure of mannitol causes it to be absorbed much more sparingly than others sugars, hence mitigating an impact on blood sugar levels;
Mannitol is not absorbed within the gastrointestinal tract unlike glucose;
It does not enter cells and can be cleared by kidney filtration.
Meaning that whatever we consume orally is mostly eliminated untouched.
Hence it can be used as a sugar substitute.
If, however, it could be absorbed into the blood…
There’d be bigger problems with issues such as the overproduction of urine (diuresis) and a possible fluid imbalance because of the osmotic pressure that it exerts.
Hence, mannitol is never prescribed orally for drug use, but it will be prescribed as an injection only if necessary.
Interestingly, it all boils down to the types of receptors that are present in our gastro-intestinal tract.
Previously, I discussed the effects of ionised Vitamin C and its effects on gastrointestinal absorption — the intestinal receptors do very much prefer to take in the ionised form of Vitamin C if it were to be ingested orally.
Whereas an injection can bypass the gastrointestinal tract and can be made available in the form of unionised Vitamin C (or ascorbic acid).
In the same way, mannitol doesn’t have that many receptors in the gastrointestinal tract that can support its transport across the intestinal lumen into the blood, hence its absorption rate is only approximately 7%. Which puts it right together with other nutrients such as natural curcumin.
It’s always key to understand the mode of transport. Even an injection can provide different results between intravenous and intramuscular injections.
But sometimes, because we don’t know enough, or we end up interpreting data wrongly…
We can fall into multiple different erroneous conclusions!
Which are best avoided — unfortunately, it’s not the easiest thing to do out there in this world swimming full of misinformation.
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