Nutritional Significance of Fructose and Sugar Alcohols

Abstract

Human metabolism of D-fructose, D-sorbitol, D-mannitol, and xylitol has been documented. In humans, sorbitol and xylitol at a single oral dose of 20 g or less and fructose at 70 g or less most likely can be fully absorbed. These there sugars can maintain, either independently or nearly independently, the integrity or the carbohydrate requirement for the growth of cells and animals. The absorption of D-mannitol is no more than 80% and is more laxative. In general, there is no adverse effect other than osmotic diarrhea after oral administration of these sugars. Transient hyperuricemia was seen in some humans. The chronic toxicity of life-long usage of these sugars in humans or other primates is not known. However, a 2-year Turku sugar studies suggested the safety of fructose and xylitol. Two-year feeding experiments in mice and rats indicated possible carcinogenicity of a high-percentage xylitol diet. Abnormalities of cellular growth were also documented in animals fed high percentages of sorbitol and sucrose. Long-term mannitol feeding experiments also revealed an increased incidence of benign thymic tumors in rats. Intravenous feeding of fructose, xylitol, and sorbitol causes major concern. The toxicity is total-dose and infusion-rate dependent. The physical toxicity induced by hyperosmolar effect of the concentrated infusion solutions can be lethal. The primary metabolic toxicities, mainly lactic acidosis and hypruricemia, are reversible. The suggested safe infusion rate of these sugars is 0.25 g/kg/h; sporadic toxic observations have been reported at this or lower doses (0.125 g/kg/h). The combination of glucose, fructose, xylitol, and sorbitol mixture intravenously is in use in Europe due to the critical threshold of each element. There are positive findings from the use of the combination in human illness (114). The beneficial effect of xylitol, mannitol, sorbitol, and fructose in decreasing order has been well documented in the prevention of dental caries in animals and in humans. Oral organisms do not appear to metabolically adapt to xylitol even after 4 years of in vivo exposure. This was based on the quantitation of xylitol dehydrogenase activity in saliva and oral organisms. In addition, a therapeutic and preventive effect for xylitol in human and animal dental caries has been demonstrated. There appears to be at least a theoretical edge in the dietary use of fructose, xylitol, and sorbitol in diabetics.(ABSTRACT TRUNCATED AT 400 WORDS)

Tolerability of oral xylitol solution in young children: Implications for otitis media prophylaxis

“…(21) The median age and weight of those in the xylitol groups whose parents reported mild gastrointestinal side effects was not materially different from the entire study cohort (16.1 months vs. 17.1 months and 10.4 kg vs. 10.9 kg, respectively), so these side effects do not appear to be particularly age-or weight-dependent. It has been shown that adaptation to xylitol and other sugar alcohols occurs rapidly, such that the laxative effect diminishes within several days of beginning regular use (1,11,12); we saw a suggestion of this phenomenon in the declining rate of gastrointestinal side effects in the xylitol groups from month one compared to months two and three.…”

“…(1)It is used widely as a bulking agent in foods and as a low-calorie sweetener in medications, dental care products, chewing gums, and candies.…”

“…The main limitation of the use of sugar alcohols is a dose-dependent osmotic laxative effect, and in adults, xylitol is well tolerated in doses up to 100 grams per day. (1,10,11) However, the tolerability of xylitol in children is not well understood, and this is particularly so in infants and toddlers. In a dose-ranging study of xylitol in 13 children seven to 16 years of age, some increase in flatulence was reported at doses of 45 grams per day, but no diarrhea was seen with doses below 65 grams per day (12); in another study of xylitol tolerability in diabetic children, only one subject out of 24 experienced diarrhea requiring discontinuation of xylitol at a dose of 30 grams per day.…”

Tecnologia supercrítica como uma alternativa para purificar xilitol biotecnológico

“…O xilitol além de ser um adoçante alternativo não cariogênico de grande valor sócio-econômico, tem se destacado na área biomédica sendo utilizado na prevenção e combate de patologias como a dermatite atópica (MASAKO et al, 2005a, b), colite pseudo-membranosa (NAABER et al, 1996), otite média aguda (KONTIOKARI; UHARI; KOSKELA, 1998), osteoporose (TISCHLER et al, 1996), anemia hemolítica (WANG; VAN EYS, 1981) e fibrose cística (ZABNER et al, 2000).…”

Enzymatic Characterization of Salmonella typhimurium Mannitol Dehydrogenase Expressed in Escherichia coli

“…Mannitol은 인체 내에서 원활하게 대사되기 어려우므로, 식 품, 화장품, 의약품 산업 분야에서 저칼로리 감미료 또는 충치 예방 등의 기능성 소재로 활용 가능하다 (Wang and Eys, 1981). 일반적으로 manntiol은 fructose와 glucose를 1:1로 섞은 후, 고온·고압 조건에서 Raney nickel 촉매에 의해 수소화하여 생산되며, 생성된 전환산물은 30% mannitol과 70% sorbitol의 혼합 형태이므로 다시 온도를 낮추고 결정화함으로써 최종적 으로 manntiol만을 회수하게 된다 (Wisnlak and Simon, 1979).…”