Are some fats more 'fattening' than other fats?

Researchers from McGill School of Dietetics in Montreal (Professor Peter Jones and colleagues) developed a blend of oil high in 'medium chain triglycerides'. (Most conventional oils/fats are high in long chain triglycerides). The ingredients of this research oil were mostly tropical oils such as palm oil and coconut oil, with some olive oil and flaxseed (linseed) oil. Apart from being high in medium chain triglycerides, it was also high in monounsaturated fat and omega 3 fat. The researchers said that their blend of oil is sent straight to the liver and burned up rather than being deposited as body fat. They studied male and female volunteers for 27 days, and despite eating the same quantity of oil as others given conventional cooking oil, the men lost an average of one pound. The women did not lose any weight. All volunteers ate a normal "north American" diet during the study.

In agreement with the above study, researchers from John Hopkins Research Institute reported at a meeting held by the American College of Cardiology, that the more saturated fats you eat (found in animal fat, hydrogenated vegetable fat) the higher the level of visceral fat (or fat that surrounds the organs in the abdomen). In contrast, a diet high in monounsaturated and polyunsaturated fat, including omega 3 fats, (found in olives, nuts, legumes, seeds, vegetable oils, fish, avocados) tends to create less visceral fat. Visceral fat is undesirable because it is linked to diabetes, hypertension and high blood fats (it is more metabolically active than fat located under the skin or subcutaneous fat).

In another study conducted by Kasai et al, published in the Asia Pacific Journal of Clinical Nutrition June 2003, showed that volunteers consuming the test bread containing medium chain triglycerides lost more weight than volunteers consuming bread containing long chain triglycerides. Click here to read the abstract (only subscribers to the journal can view the full paper).

In another US study, it was found that dieters who ate fat free yoghurt lost almost twice as much weight around their waistline compared to those who did not. The researchers suggest that the calcium in yoghurt may help the body's ability to burn fat. However, fat free yoghurt is also very low in saturarted fat which may help fat loss.

Last Updated: June 2003