Inulins and fructooligosaccharides help maintain the health of the cardiovascular system and may reduce the risk of heart disease. A key factor in this is the maintenance or improvement of blood lipid composition, through decreases in triglycerides (triacylglycerols), and the lowering of cholesterol and homocysteine levels (Hidaka et al., 2001; Luo et al., 1996; Tungland, 2003). Convincing lipid-lowering effects have been demonstrated in animals (e.g., Delzenne et al., 1993; Fiordaliso et al., 1995; Kok et al., 1998; Trautwein et al., 1998). Rats on inulin-rich diets, for example, had lower blood cholesterol and total lipid levels than control animals, while reductions in serum triglycerides were reported for rats on diets containing 5 to 20% fructooligosaccharides (Roberfroid, 1993). However, the situation is less clear-cut for humans, where higher inulin doses (over 30 gday-1) can produce adverse gastrointestinal symptoms (Williams, 1999). Some human studies have found no effects, while a number of others have shown decreases in triacylglycerol or cholesterol levels for groups taking inulin and fructooligosaccharide supplements (Williams and Jackson, 2002). Roberfroid (2005) reviewed 12 studies, finding 8 to have positive and 4 negative outcomes. Positive outcomes were more likely for subjects with moderate hyperlipidemia (Causey et al., 2000; Davidson et al., 1998; Hidaka et al., 1991; Jackson et al., 1999; Letexier et al., 2003) than for normal lipidemic volunteers (Brighenti et al., 1999; Luo et al., 1996; Pedersen et al., 1997; van Dokkum et al., 1999) or non-insulin-dependent diabetics (Alles et al., 1999; Luo et al., 2000; Yamashita et al., 1984). Inulin-type fructan supplements act to reduce lipogenesis in the liver, and this lowers lipid concentrations in the blood (Letexier et al., 2003).
Inulin and fructooligosaccharides are more effective at lowering serum levels of lipids (triglycerides) than cholesterol, with inulin more effective than short-chain fructooligosaccharides in both cases (Roberfroid, 2005). The moderate cholesterol-lowering action observed in several studies may arise as a result of the metabolism of inulin and fructooligosaccharides to short-chain fatty acids, which inhibit hepatic cholesterol biosynthesis, although the mechanism involved is not yet fully understood. Prebiotics may also help redistribute cholesterol from the blood plasma to the liver, while beneficial bacteria stimulated by prebiotics may interfere with cholesterol absorption from the colon, or directly assimilate cholesterol (Pereira and Gibson, 2002). High homocysteine levels can damage artery tissue, and interfere with the constriction and dilation of blood vessels and blood clotting processes. By lowering levels of homocysteine and undesirable lipids, inulin and fructooligosaccharide supplements may help to reduce the long-term risks of heart disease. The risk of atherosclerosis (thickening of the arteries), for example, may be reduced through a lowering of triglycerides and fatty acid levels in the blood serum.
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All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.