Originally Posted by Bazzgirl
I'm with you; I bought Mark Sisson's book but the fat thing seems so counterintuitive. I've worked hard getting my BMI down and I don't necessarily want to start eating a high fat diet. I do keep the carbs low and the protein high, though. If you start and find your body fat % goes even lower, will you please post? Thanks.
If you aren't eating as many carbs, you have to eat more fat. Fat and carb calorie balance should work like a see-saw. The body doesn't like to use protein as a fuel source (it would much rather use it for cellular/organ health, hormones, neurotransmitters, muscle building, bone mass building, immune health, etc.), so primary fuel has to come from either carbs, or fat. On paleo, the majority of this energy is derived from fat, largely monounsaturated or saturated. Protein intake should be dictated by your activity level - at least 0.5g/lb lean mass for completely sedentary individuals, and up to 2g/lb lean mass for competitive athletes. Most of us fall somewhere between that range.
The fat thing may sound counterintuitive, but the medical literature for the last 30 years has really only presented one side of the story. Based on all the research I've read over the last few years, my own conclusion is that you can lose weight and improve some health markers (depending on your own body chemistry and genetics) by sticking primarily to either fat or carbs as your main fuel source. People start running into trouble when they start consuming both fat and carbs in quantity. IMHO, high fat is preferable to high carb because of the amount of control it gives you over your blood glucose level, which can be extremely toxic when high.
If you are an active individual, carbs can help refuel you after you work out or do something taxing. As an example, I'll usually have some potato or rice/quinoa after a workout, but for most of the day and on my off days I'll generally eat a lot of fat, i.e., nuts, avocados, meat (both lean and fatty), olive oil, whole dairy, etc.
Also, in my view, vegetables don't count as carbs. It's really hard to eat 50g of carbs in the form of spinach. Fruits as well, unless you are on a clementine binge or something.