How good is the evidence for effects of rice bran oil and rice bran oi componnets on blood lipid concentrations in humans?

摘要

Rice bran oil has potential as an edible oil with hypolipidaemic effects however, at present most of the evidence for its effects comes from animal experiments. Acritical examination of the twelve published human studies shows that six of them can be discounted due to serious dsign faults. However, two well-designed human studies have shown that whole rice bran oil has hypolipidaemic properties. The hypolipidaemic reputation of #gamma#-oryzanol, a characteristic component of rice bran oil, is based entirely on four uncontrolled human studies which can be discounted. Teh two stduies on phytosterols characteristic of rice bran oil gave contradictory resutls which might be explained by the differnet classes of phytosterols studied. The single study on tocotrienols characteristic of rice bran oil suggest that these have hypolipidaemic properties. However, rice bran oil and its components may only be effective in hyperlipidaemic subjects, at high intakes and in conjunction with low-fat diets. More research into this interesting oil is needed.