Colon Cleansing - myth or gut-level magic?
I decided to use a little different approach to answering this question. I asked myself: self, what medical application would colon cleaning be used? And self answered: radiographic studies (x-rays) of the colon. Doh!
So then I went to my good friends at PubMed and asked the oricular search engine to find me the lastest. Here's what we found:
Electrolyte disorders following colonic cleansing for imaging studies.
Gutierrez-Santiago M, Garcia-Unzueta M, Amado JA, Gonzalez-Macias J, Riancho JA. Med Clin (Barc). 2006 Feb 11;126(5):173-4.
BACKGROUND AND OBJECTIVE: An adequate bowel cleansing is needed prior to radiologic and endoscopic procedures. However, it may have a number of adverse effects, including abnormalities of calcium-phosphorus homeostasis. PATIENTS AND METHOD: This was an observational prospective study in a hospital practice setting. We included consecutive inpatients (n = 47) subjected to a barium enema or colon endoscopy. Prior cleansing was done as indicated by the attending physician by using a low-salt oral poliethylenglicol (PEG) solution, oral sodium phosphate or a phosphate-containing enema. RESULTS: PEG solution frequently caused mild increases in serum sodium, and decreases in serum potassium. Oral phosphate caused a significant increase in serum phosphorus and parathormone concentrations, whereas it decreased serum calcium. Mild hyperphosphatemia was found in 57% of cases, and hypocalcemia in 36%. Phosphate enema also increased serum phosphate, causing mild hyperphosphatemia (33% cases). Although in the whole subgroup of enema-treated patients there were no significant changes in serum calcium, mild hypocalcemia was found in 27% cases.
CONCLUSIONS: Bowel cleansing procedures, particularly those using oral phosphate salts, frequently induce hyperphosphatemia and other abnormalities in serum electrolytes. Although usually transitory and without overt clinical consequences, clinicians should be aware of this potential risk, especially in elderly patients and those with impaired renal function.
Oral sodium phosphate solution: a review of its use as a colorectal cleanser.
Curran MP, Plosker GL. Drugs. 2004;64(15):1697-714.
Oral sodium phosphate solution (Fleet Phospho-soda, Casen-Fleet Fosfosoda is a low-volume, hyperosmotic agent used as part of a colorectal-cleansing preparation for surgery, x-ray or endoscopic examination. The efficacy and tolerability of oral sodium phosphate solution was generally similar to, or significantly better than, that of polyethylene glycol (PEG) or other colorectal cleansing regimens in patients preparing for colonoscopy, colorectal surgery or other colorectal-related procedures.....PHARMACOLOGICAL PROPERTIES: After the first and second 45 mL dose of oral sodium phosphate solution, the mean time to onset of bowel activity was 1.7 and 0.7 hours and the mean duration of activity was 4.6 and 2.9 hours. Bowel activity ceased within 4 hours of administration of the second dose in 83% of patients. Elevations in serum phosphorus and falls in serum total and ionised calcium from baseline occurred during the 24 hours after administration of oral sodium phosphate solution in seven healthy volunteers. These changes were not associated with significant changes in clinical assessments. The decrease in serum potassium levels after administration of oral sodium phosphate solution was negatively correlated with baseline intracellular potassium levels.
---> Sodium phosphate-associated adverse events were mostly gastrointestinal (including abdominal pain/cramping, abdominal fullness and/or bloating, anal or perianal irritation or soreness, nausea, vomiting or hunger pains), although dizziness, weakness/fatigue, thirst, chest pain, chills, headache and sleep loss were also reported.
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Okey dokey. So if you look at over the counter colon flushing products, they typically have a bulking agent, a salt (magnesium and calcium phosphates or oxides), an "herbal detoxifier" and a "probiotic tonifier".
The idea is to "loosed accumulated mucilage plaque" and to restore healthy bacterial action (hence the probiotics).
Now, the first dozen or feet or so of intentines are handling acidic residues, mostly as a liquid slurry. Tha acidity is neutralized as it passes further on in the colon, and by the time you have fecal bacterial present, much of the liquid has been absorbed and with it, nutrients, the remaining residues are largely unavailable, with respect to bacterial extraction of nutrients, by the time the extracted material becomes solid waste.
So its hard fo rme to see, if you have a diet correct in bulking/fiber agents (mostly natural soluble fiber from whole grains and insoluble fiber in fiberous vegetables and some fruits) that provide the working (absorptive) end of the gut microbial community with food (probiotics) to promote healthy gut function, that you would need to clean your proverbial clock with severe cleaning agents.
If your diet has been low in fiber and you have constipation, feel free to try these expensive treatments, but it be just as well if you are proactive in hydration and diet management, and use an occasional probiotic and even some natural prebiotics (active mixtures of microbial isolates to occasionally reintroduce some of the more prominant of the various (25-40) strains of fermentative and facultative anaerobes housed in the business end (absorptive/microbial bioconversion reactions) of the colon) as supplements.
Its not so much what these cleansers purport to do (remove accumulated mucilage) as what they do (mild intestinal upset, temporary ion imbalances, mild dehydration) that suggest they are expensive elective treatments that may do very little to remove the impacted residues they claim to treat.
Personally, I would invest in probiotics for my diet, to put supplement dollars to most effective use for gut maintenance.
