This question comes up a lot. Some use it, some don’t. You likely know that it wasn’t in Dr. Simeon’s original protocol to use any additional fats. However, some who have experimented with it feel that it either didn’t hurt their weight loss, or even improved it.
Myself, I’m not sure what to think. I have a post on coconut oil and hCG here that covers some of the same ponderings when it comes to MCT (since coconut oil has MCT in it – medium chain triglycerides).
The potential issue is, does consuming fat sources effect how the hCG hormone interacts with your body in a negative way? Dr. Simeons felt it did. Others say they lost weight the same. But it can be so hard to know for sure without bodyfat testing. You can lose weight and it can be muscle not fat. And why is it that people who have tried with other diets that couldn’t lose weight are able to with hCG? It seems like hCG makes your fat more accessible somehow. But does this also mean that fat from outside sources interacts differently with our bodies when on hCG too? Seems possible.
Ultimately I just don’t have a concrete answer for you. If you are feeling like you want to experiment, you might like to give it a try. If you were feeling like you just want to be sure you get results and not potentially waste time, you might want to stick to a more original version of the protocol, at least at first. And save some experimenting for when you’re really sick and bored of the diet. :)-
We do utilize some coconut oil in some of our P2 recipes for those who are AP (alternate protocol people) and you could easily swap that for MCT oil.