Chemistry Reference
In-Depth Information
purported health benefits of lactose derivates and what we know about their
mechanisms of action.
5.9.1.
Dental Health
Lactitol is one of a number of sugar alcohols that have found applica-
tions in products where sweetness is desired without stimulating cariogenic
bacterial activity in the mouth. Other examples include xylitol, sorbitol,
mannitol and maltitol, with the first two examples the most widely used.
Sugar alcohols are not fermented by bacteria in the mouth and so are non-
acidogenic and do not lead to bacterial exo-polysaccharide production that
contributes to dental plaque (van Loveren, 2004). Since they are small mole-
cules that are not digested, they cannot be consumed in large amounts due to
intestinal side effects (discussed later) and so are not used as bulk sweeteners,
but rather in products such as chewing gums and toothpaste. The other
lactose derivatives discussed in this chapter are also non-cariogenic, but are
not widely used specifically for oral health.
5.9.2.
Prevention and Treatment of Constipation
Lactulose (10-20 g/day) is used widely as a pharmaceutical to treat
constipation and has proven efficacy in a number of placebo-controlled trials
(Fern´ ndez-Ba ˜ ares 2006; Quah et al., 2006) even in patients with chronic
constipation. Since it is a relatively small molecule that is not digested or
absorbed, lactulose has an osmotic effect, trapping fluid, accelerating transit
in the small bowel and increasing ileocaecal flow. A recent human clinical
study has also shown that therapeutic doses of lactulose produce a prolonged
tonic contraction in the gut that may also be involved in the laxative effect
(Jou¨t et al., 2006). Since any carbohydrate that reaches the large bowel
should have a laxative effect (Macfarlane et al., 2006), the other lactose
derivatives also have benefits in the prevention and treatment of constipation.
GOSs too have been demonstrated to improve stool frequency and consis-
tency in infants and adults, though it is used more in functional foods as
opposed to pharmaceutical applications. Possible mechanisms of action of
lactose derivatives in alleviating constipation are shown in Figure 5.7.
5.9.3.
Treatment of Hepatic Encephalopathy
Hepatic encephalopathy (HE) is a neuropsychiatric condition driven by
liver dysfunction that includes a spectrum of symptoms ranging from subtle
changes in cognition and personality to lethargy, stupor and coma (Dbouk
and McGuire, 2006).
