None of the above have been proven to really help weight loss, though some have shown a very slight benefit. However, there are other benefits to taking omega oils, GLA, evening primrose, etc. I would suggest reading
www.drweil.com for more information on those. It's a very reputable resource. Coconut oil - cons outweigh the pros according to the American Heart Association as well as Dr. Weil. I personally avoid it like the plague and I say this as both a person interested in weight control as well as heart health.