A little coconut won’t hurt, but don’t be fooled by diet books that tout coconut oil as the secret ingredient for weight loss and health. Unlike most nuts that contain heart-healthy fats, the main fat in coconut is saturated fat (at  ~ 92% saturated fat, coconut oil makes butter and lard look like health food!).  However, the main saturated fat in coconut oil is lauric acid, which is a “medium-chain triglyceride” or MCT. Unlike the longer saturated fats in dairy products and meat, MCTs are shorter, more quickly absorbed, and likely to be burned for energy, rather than stored as fat.  Numerous studies show that MCTs  increase metabolism, aid in weight loss, and lower body fat.   Lauric acid also is mildly effective in protecting against liver damage, possibly aiding thyroid function, and providing some anti-inflammatory benefits. That’s the argument to justify drinking coconut-laden smoothies with 93% fat calories – hey, it’s mostly MCTs, so you’ll drop pounds just downing the shake!
Like the old adage says, “If it sounds to good to be true, it probably is.” There is no body of research on coconut and weight loss, only mixed evidence using purified MCTs. Even then, these fats appear useful mainly for hospitalized patients requiring tube feedings. For the healthy person who wants to drop a few pounds or even avoid weight gain, the research is scanty at best.  And, get this – you must consume half your calories as MCTs to see results, which is a lot more than you could realistically get from coconuts and also could cause side effects, including nerve damage and intestinal cramping.  In short, if people lose weight with coconut, it’s because they cut calories, not because they sprinkled coconut on their chicken.
OK, so coconut oil isn’t the Promised Land for weight loss, but is it good for your health? The proponents of coconut say we’ve been duped into thinking that the saturated fats in tropical oils are bad for us, pointing out that we’ve “…drastically reduced saturated fats…[which] has not solved the nation’s health problems.”  They say lauric acid in coconut oil lowers, not raises, heart-disease risk, as proven by the low rates of heart disease in coconut-eating cultures such as India.
First, saturated fats, along with trans fats, are major contributors to heart disease, it’s just that few people follow the dietary advice to cut back. Second, while cultures where people eat coconut-rich diets sometimes do have a lower incidence of disease, there is no proof it is because of coconut. It could be that these people are at low risk because they are lean, physically active, and eat traditional diets rich in fruits, vegetables, and other real foods. In contrast, adding coconut oil to the fat- and sugar-laden Western diet is like pouring kerosine on a blazing fire of obesity.
The evidence linking coconut oil to heart disease is contradictory, but points sharply in the direction of caution. Some studies show lauric acid might improve the ratio of bad cholesterol (LDL) to good cholesterol (HDL), thus lowering heart-disease risk. Even then, coconut oil is no where near as beneficial as switching from butter to olive oil.  Coconut oil also should be judged on it’s entire fat content, not just it’s lauric acid, since coconut oil also contains myristic acid, a fat that dramatically raises blood cholesterol levels. Keep in mind, decades of studies show that tropical oils, including coconut oil, actually raise, not lower, heart disease risk, which is why they were removed from processed foods in the first place. Even researchers from countries, such as India,  recommend a decrease in coconut oil consumption to reduce their rising heart-disease rates In short, if coconut has any effect on metabolism it is modest compared to its potential to raise your risk for heart disease.